Thursday, September 24, 2020

The emergence of classical BSE from atypical/ Nor98 scrapie

The emergence of classical BSE from atypical/ Nor98 scrapie

Alvina Huora,1, Juan Carlos Espinosab,1, Enric Vidalc,1, Hervé Cassarda

, Jean-Yves Doueta , Séverine Lugana , Naima Arona , Alba Marín-Morenob , Patricia Lorenzob , Patricia Aguilar-Calvob , Juan Badiolad , Rosa Bolead , Martí Pumarolae , Sylvie L. Benestadf , Leonore Orgeg , Alana M. Thackrayh , Raymond Bujdosoh , Juan-Maria Torresb , and Olivier Andreolettia,2

a UMR Institut National de la Recherche Agronomique (INRA)/École Nationale Vétérinaire de Toulouse (ENVT) 1225, Interactions Hôtes Agents Pathogènes, 31076 Toulouse, France; b Centro de Investigación en Sanidad Animal–Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, 28130 Madrid, Spain; c Centre de Recerca en Sanitat Animal, Universitat Autònoma de Barcelona (UAB)–Institut de Recerca i Tecnologia Agroalimentàries, Barcelona, Spain; d Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Universidad de Zaragoza, 50013 Zaragoza, Spain; e Unit of Murine and Comparative Pathology, UAB, 08193 Barcelona, Spain; f Norwegian Veterinary Institute, N-0106 Oslo, Norway; g Laboratory of Pathology, National Institute for Agrarian and Veterinary Research, 2780-157 Oeiras, Portugal; and h Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, United Kingdom

Edited by Michael B. A. Oldstone, Scripps Research Institute, La Jolla, CA, and approved November 15, 2019 (received for review September 11, 2019)

Atypical/Nor98 scrapie (AS) is a prion disease of small ruminants. Currently there are no efficient measures to control this form of prion disease, and, importantly, the zoonotic potential and the risk that AS might represent for other farmed animal species remains largely unknown. In this study, we investigated the capacity of AS to propagate in bovine PrP transgenic mice. Unexpectedly, the transmission of AS isolates originating from 5 different European countries to bovine PrP mice resulted in the propagation of the classical BSE (c-BSE) agent. Detection of prion seeding activity in vitro by protein misfolding cyclic amplification (PMCA) demonstrated that low levels of the c-BSE agent were present in the original AS isolates. C-BSE prion seeding activity was also detected in brain tissue of ovine PrP mice inoculated with limiting dilutions (endpoint titration) of ovine AS isolates. These results are consistent with the emergence and replication of c-BSE prions during the in vivo propagation of AS isolates in the natural host. These data also indicate that c-BSE prions, a known zonotic agent in humans, can emerge as a dominant prion strain during passage of AS between different species. These findings provide an unprecedented insight into the evolution of mammalian prion strain properties triggered by intra- and interspecies passage. From a public health perspective, the presence of c-BSE in AS isolates suggest that cattle exposure to small ruminant tissues and products could lead to new occurrences of c-BSE.

Transmissible spongiform encephalopathies (TSEs), or prion diseases, are fatal neurodegenerative disorders that affect a large spectrum of mammalian species. These conditions include scrapie in small ruminants, classical bovine spongiform encephalopathy (c-BSE) in cattle, and sporadic Creutzfeldt–Jakob disease (sCJD) or variant CJD (vCJD) in humans. The fundamental event in prion propagation is the conversion of the normal cellular prion protein (PrPC ) into an abnormal diseaseassociated isoform (PrPSc) in tissues of infected individuals. PrPC is completely degraded by digestion with proteinase K (PK), whereas PrPSc is N-terminally truncated, resulting in a PK-resistant core termed PrPres (1). According to the prion concept, PrPSc is the principal, if not sole, component of the transmissible prion agent (2), and PrPres is a disease marker for prion diseases (1, 3). Particular biochemical properties of PrPSc, such as detergent solubility, PK resistance, and electromobility evidenced by Western blot can be used to distinguish between different prion agents or strains (4, 5). Intraspecies transmission of prion disease between individuals is typically quite efficient. In contrast, interspecies transmission of prions can be unpredictable, with apparent failure of disease transmission on many occasions. In other cases, clinical prion disease may not be evident but, rather, there is the presence of subclinical infection (6). When interspecies prion transmission does occur, the propagating agent can remain identical to the original prion strain or can display different biological properties compared to the original inoculum (7, 8). This complex set of outcomes for interspecies prion challenge are collectively referred to as the transmission barrier phenomenon.

After identification of the gene encoding PrP, it was soon discovered that differences in amino acid sequence between host PrPC and donor PrPSc constitutes the principal determinant of the transmission barrier. For example, the resistance of wild-type mice to clinical prion disease induced by hamster scrapie is abrogated by transgenic expression of hamster PrPC in mice (9, 10). As a consequence, mice genetically engineered to express particular species forms of PrP sequence, in the absence of endogenous mouse PrP, have emerged as relevant models to experimentally characterize the outcome of prion strain transmission between species (11). It is also now well established that strain properties have a significant impact on the ability of prions to cross the species barrier. For instance, human vCJD can be transmitted readily to conventional mice, but it is extremely difficult for sCJD to propagate in the same mouse lines (12, 13). Furthermore, the amino acid sequence of PrPSc influences the efficacy of interspecies

Significance

The origin of transmissible BSE in cattle remains unestablished. Sheep scrapie is a potential source of this known zoonotic. Here we investigated the capacity of sheep scrapie to propagate in bovine PrP transgenic mice. Unexpectedly, transmission of atypical but not classical scrapie in bovine PrP mice resulted in propagation of classical BSE prions. Detection of prion seeding activity by in vitro protein misfolding cyclic amplification demonstrated BSE prions in the original atypical scrapie isolates. BSE prion seeding activity was also detected in ovine PrP mice inoculated with limiting dilutions of atypical scrapie. Our data demonstrate that classical BSE prions can emerge during intraand interspecies passage of atypical scrapie and provide an unprecedented insight into the evolution of mammalian prions.

snip...see full text;


*** Scrapie Field Trial Experiments Mission, Texas, The Moore Air Force Base Scrapie Experiment 1964 ***
 
*** How Did CWD Get Way Down In Medina County, Texas?
 
Confucius ponders...
 
Could the Scrapie experiments back around 1964 at Moore Air Force near Mission, Texas, could this area have been ground zero for CWD TSE Prion (besides the CWD cases that have waltzed across the Texas, New Mexico border near WSMR Trans Pecos region since around 2001)?
 
Epidemiology of Scrapie in the United States 1977
 
snip...
 
Scrapie Field Trial Experiments Mission, Texas
 
A Scrapie Field Trial was developed at Mission, Texas, to provide additional information for the eradication program on the epidemiology of natural scrapie. The Mission Field Trial Station is located on 450 acres of pastureland, part of the former Moore Air Force Base, near Mission, Texas. It was designed to bring previously exposed, and later also unexposed, sheep or goats to the Station and maintain and breed them under close observation for extended periods to determine which animals would develop scrapie and define more closely the natural spread and other epidemiological aspects of the disease.
 
The 547 previously exposed sheep brought to the Mission Station beginning in 1964 were of the Cheviot, Hampshire, Montadale, or Suffolk breeds. They were purchased as field outbreaks occurred, and represented 21 bloodlines in which scrapie had been diagnosed. Upon arrival at the Station, the sheep were maintained on pasture, with supplemental feeding as necessary. The station was divided into 2 areas: (1) a series of pastures and-pens occupied by male animals only, and (2) a series of pastures and pens occupied by females and young progeny of both sexes. ...
 
snip...see full text ;
 

uesday, June 07, 2016
 
How Did CWD Get Way Down In Medina County, Texas?
 
 
Thursday, June 09, 2016
 
Scrapie Field Trial Experiments Mission, Texas, The Moore Air Force Base Scrapie TSE Prion Experiment 1964
 
How Did CWD Get Way Down In Medina County, Texas?
 

MISSION, TEXAS, USA SCRAPIE TEST TO USA CATTLE DEVELOPED DIFFERENT STRAIN OF BSE TSE PRION

31

Appendix I VISIT TO USA - OR A E WRATHALL — INFO ON BSE AND SCRAPIE

Dr Clark lately of the scrapie Research Unit, Mission Texas has

successfully transmitted ovine and caprine scrapie to cattle. The

experimental results have not been published but there are plans to do

this. This work was initiated in 1978. A summary of it is:-

Expt A 6 Her x Jer calves born in 1978 were inoculated as follows with

a 2nd Suffolk scrapie passage:-

i/c 1ml; i/m, 5ml; s/c 5ml; oral 30ml.

1/6 went down after 48 months with a scrapie/BSE-like disease.

Expt B 6 Her or Jer or HxJ calves were inoculated with angora Goat

virus 2/6 went down similarly after 36 months.

Expt C Mice inoculated from brains of calves/cattle in expts A & B were resistant, only 1/20 going down with scrapie and this was the reason given for not publishing.

Diagnosis in A, B, C was by histopath. No reports on SAF were given.

Dr Warren Foote indicated success so far in eliminating scrapie in offspring from experimentally— (and naturally) infected sheep by ET. He had found difficulty in obtaining embryos from naturally infected sheep (cf SPA).

Prof. A Robertson gave a brief accout of BSE. The us approach was to

32

accord it a very low profile indeed. Dr A Thiermann showed the picture in the "Independent" with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs.

BSE was not reported in USA.

4. Scrapie incidents (ie affected flocks) have shown a dramatic increase since 1978. In 1953 when the National Control scheme was started there were 10-14 incidents, in 1978 - 1 and in 1988 so far 60.

5. Scrapie agent was reported to have been isolated from a solitary fetus.

6. A western blotting diagnostic technique (? on PrP) shows some promise.

7. Results of a questionnaire sent to 33 states on the subject of the national sheep scrapie programme survey indicated

17/33 wished to drop it

6/33 wished to develop it

8/33 had few sheep and were neutral

Information obtained from Dr Wrathall‘s notes of a meeting of the u.s.

Animal Health Association at Little Rock, Arkansas Nov. 1988.

33

In Confidence - Perceptions of unconventional slow virus diseases of animals in the USA - APRIL-MAY 1989 - G A H Wells

3. Prof. A. Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs. ...


57 

The experiment which might have determined whether BSE and scrapie were caused by the same agent (ie, the feeding of natural scrapie to cattle) was never undertaken in the UK. 

It was, however, performed in the USA in 1979, when it was shown that cattle inoculated with the scrapie agent endemic in the flock of Suffolk sheep at the United States Department of Agriculture in Mission, Texas, developed a TSE quite unlike BSE. 32 

The findings of the initial transmission, though not of the clinical or neurohistological examination, were communicated in October 1988 to Dr Watson, Director of the CVL, following a visit by Dr Wrathall, one of the project leaders in the Pathology Department of the CVL, to the United States Department of Agriculture. 33 

The results were not published at this point, since the attempted transmission to mice from the experimental cow brain had been inconclusive. 

The results of the clinical and histological differences between scrapie-affected sheep and cattle were published in 1995. 

Similar studies in which cattle were inoculated intracerebrally with scrapie inocula derived from a number of scrapie-affected sheep of different breeds and from different States, were carried out at the US National Animal Disease Centre. 34 

The results, published in 1994, showed that this source of scrapie agent, though pathogenic for cattle, did not produce the same clinical signs of brain lesions characteristic of BSE..

32 Clark, W., Hourrigan, J. and Hadlow, W. (1995) Encephalopathy in Cattle Experimentally Infected with the Scrapie Agent, American Journal of Veterinary Research, 56, 606-12

33 YB88/10.00/1.1 


also see hand written notes ;


Evidence That Transmissible Mink Encephalopathy Results from Feeding Infected Cattle

Over the next 8-10 weeks, approximately 40% of all the adult mink on the farm died from TME.

snip...

The rancher was a ''dead stock'' feeder using mostly (>95%) downer or dead dairy cattle...


EVIDENCE OF SCRAPIE IN SHEEP AS A RESULT OF FOOD BORNE EXPOSURE

This is provided by the statistically significant increase in the incidence of sheep scrape from 1985, as determined from analyses of the submissions made to VI Centres, and from individual case and flock incident studies. ........


REPORT OF THE WORKING PARTY ON BOVINE SPONGIFORM ENCEPHALOPATHY 1989

snip...

4.2.9 ...Also, if it resulted from a localised chance transmission of the scrapie strain from sheep to cattle giving rise to a mutant, a different pattern of disease would have been expected: its range would have increased with time. Thus the evidence from Britain is against the disease being due to a new strain of the agent, but we note that in the United States from 1984 to 1988 outbreaks of scrapie in sheep flocks are reported to have Increased markedly, now being nearly 3 times as high as during any previous period (18). 




IBNC BSE TSE Prion mad cow disease

 ***however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not detected using rapid tests for BSE.

***Subsequent testing resulted in the detection of pathologic lesion in unusual brain location and PrPsc detection by PMCA only.

*** IBNC Tauopathy or TSE Prion disease, it appears, no one is sure ***

Posted by Terry S. Singeltary Sr. on 03 Jul 2015 at 16:53 GMT


SEE FULL TEXT OF ALL THIS HERE ;

2009 UPDATE ON ALABAMA AND TEXAS MAD COWS 2005 and 2006


ALABAMA MAD COW CASE



Saturday, August 14, 2010

BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and VPSPr PRIONPATHY

(see COPIOUS AMOUNTS OF mad cow feed in COMMERCE IN ALABAMA...TSS)



P.9.21

Molecular characterization of BSE in Canada

Jianmin Yang 1 , Sandor Dudas 2 , Catherine Graham 2 , Markus Czub 3 , Tim McAllister 1 , Stefanie Czub 1 1 Agriculture and Agri-Food Canada Research Centre, Canada; 2 National and OIE BSE Reference Laboratory, Canada; 3 University of Calgary, Canada

Background: Three BSE types (classical and two atypical) have been identified on the basis of molecular characteristics of the misfolded protein associated with the disease. To date, each of these three types have been detected in Canadian cattle. Objectives: This study was conducted to further characterize the 16 Canadian BSE cases based on the biochemical properties of there associated PrPres.

Methods: Immuno-reactivity, molecular weight, glycoform profiles and relative proteinase K sensitivity of the PrPres from each of the 16 confirmed Canadian BSE cases was determined using modified Western blot analysis.

Results: Fourteen of the 16 Canadian BSE cases were C type, 1 was H type and 1 was L type. The Canadian H and L-type BSE cases exhibited size shifts and changes in glycosylation similar to other atypical BSE cases. PK digestion under mild and stringent conditions revealed a reduced protease resistance of the atypical cases compared to the C-type cases. N terminal-specific antibodies bound to PrPres from H type but not from C or L type. The C-terminal-specific antibodies resulted in a shift in the glycoform profile and detected a fourth band in the Canadian H-type BSE.

Discussion: The C, L and H type BSE cases in Canada exhibit molecular characteristics similar to those described for classical and atypical BSE cases from Europe and Japan. This supports the theory that the importation of BSE contaminated feedstuff is the source of C-type BSE in Canada. It also suggests a similar cause or source for atypical BSE in these countries.

Discussion: The C, L and H type BSE cases in Canada exhibit molecular characteristics similar to those described for classical and atypical BSE cases from Europe and Japan.

*** This supports the theory that the importation of BSE contaminated feedstuff is the source of C-type BSE in Canada.

*** It also suggests a similar cause or source for atypical BSE in these countries. ***

see page 176 of 201 pages...tss



*** Singeltary reply ; Molecular, Biochemical and Genetic Characteristics of BSE in Canada Singeltary reply;




Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform EncephalopathiesTitle: The pathogenesis, detection, and control of scrapie in sheep 

Author
itemCASSMANN, ERIC - Oak Ridge Institute For Science And Education (ORISE)
itemGreenlee, Justin

Submitted to: American Journal of Veterinary Research 
Publication Type: Review Article 
Publication Acceptance Date: 12/4/2019 
Publication Date: 7/20/2020 
Citation: Cassmann, E.D., Greenlee, J.J. 2020. The pathogenesis, detection, and control of scrapie in sheep. American Journal of Veterinary Research. 81(7):600-614. https://doi.org/10.2460/ajvr.81.7.600.
DOI: https://doi.org/10.2460/ajvr.81.7.600
Interpretive Summary:
Technical Abstract: Sheep scrapie is a fatal neurologic disease that is caused by an infectious misfolded protein called a prion. The prion protein is encoded by an endogenous gene, PRNP, and it resides in high concentrations within the central nervous system. A broad range of functions for the prion protein have been uncovered, but the entire range of function is undetermined. In the misfolded conformation, prion accumulation results in neurodegeneration. There are several naturally occurring polymorphisms in the PRNP gene, and there is a strong correlation between disease susceptibility and the PRNP genotype. The cornerstone of many scrapie eradication programs is selection of scrapie resistant genotypes. The transmission of scrapie often occurs between sheep in the periparturient period when lambs are the most susceptible due to higher densities of gut-associated lymphoid tissue. Subsequently, prions are disseminated to the lymphoid system and spread to the central nervous system. The shedding of prions occurs prior to the onset of clinical signs. In contrast to classical scrapie, atypical scrapie is a spontaneous form of scrapie that occurs in individual older animals within a flock. It is not considered to be naturally infectious. This review addresses the current diagnostic modalities and techniques for studying scrapie in sheep. The examination of disease characteristics aims to identify the etiology and diagnose prion diseases. Scrapie transmission to other species including deer has been demonstrated experimentally, as well as the transmission of non-scrapie prion diseases to sheep. Finally, the effectiveness of the United States scrapie eradication program is reviewed.
Title: Scrapie in white-tailed deer: a strain of the CWD agent that efficiently transmits to sheep? 

Author
itemGreenlee, Justin
itemKOKEMULLER, ROBYN - US Department Of Agriculture (USDA)
itemMOORE, S - Oak Ridge Institute For Science And Education (ORISE)
itemWEST GREENLEE, M - Iowa State University

Submitted to: Meeting Abstract 
Publication Type: Abstract Only 
Publication Acceptance Date: 3/29/2019 
Publication Date: N/A 
Citation: N/A
Interpretive Summary:
Technical Abstract: Scrapie is a transmissible spongiform encephalopathy of sheep and goats that is associated with widespread accumulation of abnormal prion protein (PrPSc) in the central nervous and lymphoid tissues. Chronic wasting disease (CWD) is the natural prion disease of cervid species, and the tissue distribution of PrPSc in affected cervids is similar to scrapie in sheep. There are several lines of evidence that suggest that multiple strains of CWD exist, which may affect the agent’s potential to transmit to hosts of the same or different species. We inoculated white-tailed deer with the scrapie agent from ARQ/ARQ sheep, which resulted in 100% attack rates by either the intracranial or oronasal route of inoculation. When examining tissues from the brainstems or lymphoid tissues by traditional diagnostic methods such as immunohistochemistry or western blots, it is difficult to differentiate tissues from deer infected with scrapie from those infected with CWD. However, there are several important differences between tissues from scrapie-infected white-tailed deer (WTD scrapie) and those infected with CWD (WTD CWD). First, there are different patterns of PrPSc deposition in the brains of infected deer: brain tissues from deer with WTD scrapie had predominantly particulate and stellate immunoreactivity whereas those from deer with WTD-CWD had large aggregates and plaque-like staining. Secondly, the incubation periods of WTD scrapie isolates are longer than CWD isolates in mice expressing cervid prion protein. Most notably, the transmission potential of these two isolates back to sheep is distinctly different. Attempts to transmit various CWD isolates to sheep by the oral or oronasal routes have been unsuccessful despite observation periods of up to 7 years. However, WTD scrapie efficiently transmitted back to sheep by the oronasal route. Upon transmission back to sheep, the WTD scrapie isolate exhibited different phenotypic properties when compared to the sheep receiving the original sheep scrapie inoculum including different genotype susceptibilities, distinct PrPSc deposition patterns, and much more rapid incubation periods in transgenic mice expressing the ovine prion protein. The scrapie agent readily transmits between sheep and deer after oronasal exposure. This could confound the identication of CWD strains in deer and the eradication of scrapie from sheep.
Title: Passage of scrapie to deer results in a new phenotype upon return passage to sheep 

Author
itemGreenlee, Justin
itemKokemuller, Robyn
itemMOORE, SARAH - Orise Fellow
itemWEST GREENLEE, N - Iowa State University

Submitted to: Prion 
Publication Type: Abstract Only 
Publication Acceptance Date: 3/15/2017 
Publication Date: N/A 
Citation: N/A
Interpretive Summary:
Technical Abstract: Aims: We previously demonstrated that scrapie has a 100% attack rate in white-tailed deer after either intracranial or oral inoculation. Samples from deer that developed scrapie had two different western blot patterns: samples derived from cerebrum had a banding pattern similar to the scrapie inoculum, but samples from brainstem had a banding pattern similar to CWD. In contrast, transmission of CWD from white-tailed deer to sheep by the intracranial route has a low attack rate and to-date oronasal exposure has been unsuccessful. The purpose of this study was to determine if sheep are susceptible to oronasal exposure of the scrapie agent derived from white-tailed deer. 
Methods: At approximately 5 months of age, Suffolk sheep of various PRNP genotypes were challenged by the oronasal route with 10% brain homogenate derived from either the cerebrum or the brainstem of scrapie-affected deer. Genotypes represented in each inoculation group were VV136RR154QQ171 (n=2), AA136RR154QQ171 (n=2), and AV136RR154QR171 (n=1). After inoculation, sheep were observed daily for clinical signs. Upon development of clinical signs, sheep were killed with an overdose of pentobarbital sodium and necropsied. Tissue samples were tested for the presence of PrPSc by EIA, western blot, and immunohistochemistry (IHC). The No. 13-7 scrapie inoculum used for the deer has a mean incubation period of 20.1 months in sheep with the AA136RR154QQ171 genotype and 26.7 months in sheep with the VV136RR154QQ171 genotype. 
Results: Sheep inoculated oronasally with WTD derived scrapie developed disease, but only after inoculation with the inoculum from the cerebrum that had a scrapie-like profile. The first sheep to develop clinical signs at approximately 29 months post inoculation had the VV136RR154QQ171 genotype. Eventually sheep of the AA136RR154QQ171 genotype developed clinical signs, but at a mean incubation of 52 months. At 62 months post-inoculation, none of the sheep inoculated with material from the deer brainstem have developed clinical disease. 
Conclusions: The No. 13-7 inoculum used in the original deer experiment readily infects white-tailed deer and sheep of various genotypes by the oronasal route. When inoculum is made from different brain regions of No 13-7 scrapie-infected deer from either cerebrum with a scrapie-like western blot pattern or brainstem with a CWD-like western blot pattern, sheep with the VV136RR154QQ171 genotype are the first to develop clinical signs. This is in contrast to the original No. 13-7 inoculum that has a faster incubation period in sheep with the AA136RR154QQ171 genotype. Similar to experiments conducted with CWD, sheep oronasally inoculated with brainstem material from deer with a CWD-like molecular profile have no evidence of disease after 62 months of incubation. While scrapie is not known to occur in free-ranging populations of white-tailed deer, experimental cases are difficult to differentiate from CWD. This work raises the potential concern that scrapie infected deer could serve as a confounding factor to scrapie eradication programs as scrapie from deer seems to be transmissible to sheep by the oronasal route.
Title: Sheep are susceptible to the agent of TME by intracranial inoculation and have evidence of infectivity in lymphoid tissues 

Author
itemCASSMANN, ERIC - Oak Ridge Institute For Science And Education (ORISE)
itemMOORE, SARA - Oak Ridge Institute For Science And Education (ORISE)
itemSMITH, JODI - Iowa State University
itemGreenlee, Justin

Submitted to: Frontiers in Veterinary Science 
Publication Type: Peer Reviewed Journal 
Publication Acceptance Date: 11/14/2019 
Publication Date: 11/29/2019 
Citation: Cassmann, E.D., Moore, S.J., Smith, J.D., Greenlee, J.J. 2019. Sheep are susceptible to the agent of TME by intracranial inoculation and have evidence of infectivity in lymphoid tissues. Frontiers in Veterinary Science. 6:430. https://doi.org/10.3389/fvets.2019.00430.
DOI: https://doi.org/10.3389/fvets.2019.00430
Interpretive Summary: Prion diseases are protein misfolding diseases that are transmissible between animals. The outcome of prion infection is irreversible brain damage and death. Transmission can occur between animals of the same or different species, however, transmission between different species is usually less efficient due to the species barrier, which results from differences in the amino acid sequence of the prion protein between the donor and recipient species. The present work evaluated whether transmissible mink encephalopathy (TME) can infect sheep. Our results demonstrate that sheep are susceptible to the TME agent and that the TME agent has similar properties to the agent of L-type atypical bovine spongiform encephalopathy (L-BSE). This work supports the ideas that L-BSE is a possible source for TME in mink and that the practice of feeding cattle with neurologic disease to mink should be avoided. This information is important to farmers who raise cattle, sheep, or mink.
Technical Abstract: Transmissible mink encephalopathy (TME) is a food borne prion disease. Epidemiological and experimental evidence suggests similarities between the agent of TME and L-BSE. This experiment demonstrates the susceptibility of four different genotypes of sheep to the agent of TME by intracranial inoculation. The four genotypes of sheep used in this experiment had polymorphisms corresponding to codons 136 and 171 of the prion gene: VV136QQ171, AV136QQ171, AA136QQ171, and AA136QR171. All intracranially inoculated sheep without comorbidities (15/15) developed clinical scrapie and had detectable PrPSc by immunohistochemistry, western blot, and enzyme immunoassay (EIA). The mean incubation periods in TME infected sheep correlated with their relative genotypic susceptibility. There was peripheral distribution of PrPSc in the trigeminal ganglion and neuromuscular spindles; however, unlike classical scrapie and C-BSE in sheep, ovine TME did not accumulate in the lymphoid tissue. To rule out the presence of infectious, but proteinase K susceptible PrPSc, the lymph nodes of two sheep genotypes, VV136QQ171 and AA136QQ171, were bioassayed in transgenic ovinized mice. None of the mice (0/32) inoculated by the intraperitoneal route had detectable PrPSc by EIA. Interestingly, mice intracranially inoculated with RPLN tissue from a VV136QQ171 sheep were EIA positive (3/17) indicating that sheep inoculated with TME harbor infectivity in their lymph nodes. Western blot analysis demonstrated similarities in the migration patterns between ovine TME and the bovine TME inoculum. Overall, these results demonstrate that sheep are susceptible to the agent of TME, and that the tissue distribution of PrPSc in TME infected sheep is distinct from classical scrapie.
Title: The agent of transmissible mink encephalopathy passaged in sheep is similar to BSE-L 

Author
itemCASSMANN, E - Oak Ridge Institute For Science And Education (ORISE)
itemGreenlee, Justin
itemBALKEMA-BUSCHMANN, A - Friedrich-Loeffler-institut
itemGROSCHUP, M - Friedrich-Loeffler-institut
itemMOORE, S - Oak Ridge Institute For Science And Education (ORISE)
itemKokemuller, Robyn

Submitted to: Meeting Abstract 
Publication Type: Abstract Only 
Publication Acceptance Date: 3/29/2019 
Publication Date: N/A 
Citation: N/A
Interpretive Summary:
Technical Abstract: Transmissible mink encephalopathy (TME) is a fatal neurologic prion disease of farmed mink. Epidemiologic and experimental evidence following a Wisconsin outbreak in 1985 has linked TME to low-type bovine spongiform encephalopathy (BSE-L). Evidence suggests that farmed mink were likely exposed to BSE-L infected downer cattle that were fed to the mink. The interspecies transmission of TME to cattle has been documented. Recently, we demonstrated the susceptibility of sheep to cattle passaged TME by intracranial inoculation. The aim of the present study was to compare ovine passaged cattle TME to other prion diseases of food-producing animals. Using a transgenic mouse model, we characterized the disease phenotype of sheep TME to BSE-C and BSE-L. Separate inoculants of sheep passaged TME were derived from animals with the VRQ/VRQ (VV136) and ARQ/VRQ (AV136) prion protein genotype. Transgenic bovinized mice (TgBovXV) were intracranially inoculated with 20 µl of 1% w/v brain homogenate. The disease phenotypes were characterized by comparing the attack rates, incubation periods, and vacuolation profiles in TgBovXV mice. The attack rate for BSE-C (13/13), BSE-L (18/18), and TMEVV (21/21) was 100%; whereas, the TMEAV group (15/19) had an incomplete attack rate. The average incubation periods were 299, 280, 310, and 535 days, respectively. The vacuolation profiles of BSE-L and TMEVV were most similar with mild differences observed in the thalamus and medulla. Vacuolation profiles from the BSE-C and TMEAV experimental groups were different than TMEVV and BSE-L. Overall the phenotype of disease in TME inoculated transgenic mice was dependent on the sheep donor genotype (VV vs AV). The results of the present study indicate that TME isolated from VRQ/VRQ sheep is similar to BSE-L by incubation period, attack rate, and vacuolation profile. Our findings are in agreement with previous research that found similarities between BSE-L and TME. In this study, the similarities between TME and BSE-L are maintained after multiple interspecies passages.
Title: Sheep are susceptible to the agent of transmissible mink encephalopathy after intracranial inoculation 

Author
itemCASSMAN, E - Iowa State University
itemMOORE, S - Orise Fellow
itemSMITH, J - Iowa State University
itemGreenlee, Justin

Submitted to: American Association of Veterinary Laboratory Diagnosticians 
Publication Type: Abstract Only 
Publication Acceptance Date: 7/20/2018 
Publication Date: N/A 
Citation: N/A
Interpretive Summary:
Technical Abstract: Transmissible spongiform encephalopathies (TSE) are fatal neurodegenerative diseases caused by an infectious protein (prion). Naturally occurring prion diseases include bovine spongiform encephalopathy (BSE), scrapie in small ruminants, chronic wasting disease in cervids, transmissible mink encephalopathy (TME), Creutzfeldt-Jakob disease (CJD) in humans, and camel prion disease. An epizootic of BSE in the UK revealed the zoonotic potential of prion diseases when variant-CJD arose in people who had consumed products from cattle infected with classical BSE (C-BSE). Spontaneously arising cases of atypical BSE (L-BSE and H-BSE ) with molecular phenotypes distinct from C-BSE were first recognized in 2004. The origin of C-BSE is unknown, but evidence shows BSE infected carcasses rendered for cattle feed amplified the outbreak. The emergence of C-BSE-like strains after serial passage of H-BSE in mice have been demonstrated. One hypothesis for the origin of C-BSE is its emergence after multi-species transmission of a food-borne atypical BSE. TME has been described as a food-borne TSE; evidence suggests that TME may have originated from feeding TSE-affected downer cows to mink. Experimental transmission of TME in cattle produces molecular phenotype on western blot very similar to L-BSE. Since the emergence of C-BSE could be due to cross-species transmission and adaptability, we investigated the susceptibility and disease phenotype of bovine passaged TME (3x) inoculated into sheep. We inoculated sheep with brain homogenate from cattle clinically ill with TME: 17 intracerebral (IC) and 12 oronasal (ON). Sheep inoculated ON did not develop clinical disease and PrPSc was not detected. In the IC group, 15/17 sheep developed spongiform encephalopathy and PrPSc within the CNS detected by ELISA and IHC. Several sheep had PrPSc in neuromuscular spindles, and one sheep had PrPSc in the myenteric plexus of the small intestine. No sheep had lymphoreticular (LR) PrPSc. Two sheep died early due to intercurrent disease; they did not have detectable PrPSc by ELISA, western blot, or IHC. Non-CNS PrPSc tissue distribution is mostly host dependent. The absence of LR PrPSc in sheep is a uncommon finding. Sheep tend to accumulate PrPSc in LR tissue independent of the TSE type and route. Contrariwise, our findings demonstrate that bovine adapted TME causes a non-LR phenotype in sheep similar to those seen in bovine TSEs. However, unlike cows infected with TME (1st and 2nd passage), sheep accumulated PrPSc in the neuromuscular spindles. In conclusion, we found that sheep are susceptible to bovine passaged TME by the intracerebral route and resistant to oronasal transmission at the dosage used in this experiment. The incubation periods in affected sheep were associated with their genotype with incubation being more rapid in the VRQ haplotype.
Title: The agent of H-type bovine spongiform encephalopathy associated with E211K prion protein polymorphism transmits after oronasal challenge 

Author
itemGreenlee, Justin
itemMOORE, S - Orise Fellow
itemWEST-GREENLEE, M - Iowa State University

Submitted to: Prion 
Publication Type: Abstract Only 
Publication Acceptance Date: 5/14/2018 
Publication Date: 5/22/2018 
Citation: Greenlee, J.J., Moore, S.J., West Greenlee, M.H. 2018. The agent of H-type bovine spongiform encephalopathy associated with E211K prion protein polymorphism transmits after oronasal challenge. Prion 2018, May 22-25, 2018, Santiago de Compostela, Spain. Paper No. P98, page 116.
Interpretive Summary:
Technical Abstract: In 2006, a case of H-type bovine spongiform encephalopathy (BSE) was reported in a cow with a previously unreported prion protein polymorphism (E211K). The E211K polymorphism is heritable and homologous to the E200K mutation in humans that is the most frequent PRNP mutation associated with familial Creutzfeldt-Jakob disease. Although the prevalence of the E211K polymorphism is low, cattle carrying the K211 allele develop H-type BSE with a rapid onset after experimental inoculation by the intracranial route. The purpose of this study was to investigate whether the agents of H-type BSE or H-type BSE associated with the E211K polymorphism transmit to wild type cattle or cattle with the K211 allele after oronasal exposure. Wild type (EE211) or heterozygous (EK211) cattle were oronasally inoculated with either H-type BSE from the 2004 US H-type BSE case (n=3) or from the 2006 US H-type case associated with the E211K polymorphism (n=4) using 10% w/v brain homogenates. Cattle were observed daily throughout the course of the experiment for the development of clinical signs. At approximately 50 months post-inoculation, one steer (EK211 inoculated with E211K associated H-BSE) developed clinical signs including inattentiveness, loss of body condition, weakness, ataxia, and muscle fasciculations and was euthanized. Enzyme immunoassay confirmed that abundant misfolded protein was present in the brainstem, and immunohistochemistry demonstrated PrPSc throughout the brain. Western blot analysis of brain tissue from the clinically affected steer was consistent with the E211K H-type BSE inoculum. With the experiment currently at 55 months post-inoculation, no other cattle in this study have developed clinical signs suggestive of prion disease. This study demonstrates that the H-type BSE agent is transmissible by the oronasal route. These results reinforce the need for ongoing surveillance for classical and atypical BSE to minimize the risk of potentially infectious tissues entering the animal or human food chains.
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research

Title: Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease 

Author item MOORE, SARAH - Orise Fellow item Kunkle, Robert item KONDRU, NAVEEN - Iowa State University item MANNE, SIREESHA - Iowa State University item SMITH, JODI - Iowa State University item KANTHASAMY, ANUMANTHA - Iowa State University item WEST GREENLEE, M - Iowa State University item Greenlee, Justin Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 3/15/2017 Publication Date: N/A Citation: N/A Interpretive Summary:

Technical Abstract: Aims: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of cervids. We previously demonstrated that disease-associated prion protein (PrPSc) can be detected in the brain and retina from pigs challenged intracranially or orally with the CWD agent. In that study, neurological signs consistent with prion disease were observed only in one pig: an intracranially challenged pig that was euthanized at 64 months post-challenge. The purpose of this study was to use an antigen-capture immunoassay (EIA) and real-time quaking-induced conversion (QuIC) to determine whether PrPSc is present in lymphoid tissues from pigs challenged with the CWD agent. 

Methods: At two months of age, crossbred pigs were challenged by the intracranial route (n=20), oral route (n=19), or were left unchallenged (n=9). At approximately 6 months of age, the time at which commercial pigs reach market weight, half of the pigs in each group were culled (<6 month challenge groups). The remaining pigs (>6 month challenge groups) were allowed to incubate for up to 73 months post challenge (mpc). The retropharyngeal lymph node (RPLN) was screened for the presence of PrPSc by EIA and immunohistochemistry (IHC). The RPLN, palatine tonsil, and mesenteric lymph node (MLN) from 6-7 pigs per challenge group were also tested using EIA and QuIC. 

Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). 

Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.



Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research

Title: The agent of chronic wasting disease from pigs is infectious in transgenic mice expressing human PRNP 

Author item MOORE, S - Orise Fellow item Kokemuller, Robyn item WEST-GREENLEE, M - Iowa State University item BALKEMA-BUSCHMANN, ANNE - Friedrich-Loeffler-institut item GROSCHUP, MARTIN - Friedrich-Loeffler-institut item Greenlee, Justin Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 5/10/2018 Publication Date: 5/22/2018 Citation: Moore, S.J., Kokemuller, R.D., West-Greenlee, M.H., Balkema-Buschmann, A., Groschup, M.H., Greenlee, J.J. 2018. The agent of chronic wasting disease from pigs is infectious in transgenic mice expressing human PRNP. Prion 2018, Santiago de Compostela, Spain, May 22-25, 2018. Paper No. WA15, page 44.

Interpretive Summary:

Technical Abstract: We have previously shown that the chronic wasting disease (CWD) agent from white-tailed deer can be transmitted to domestic pigs via intracranial or oral inoculation although with low attack rates and restricted PrPSc accumulation. The objective of this study was to assess the potential for cross-species transmission of pig-passaged CWD using bioassay in transgenic mice. Transgenic mice expressing human (Tg40), bovine (TgBovXV) or porcine (Tg002) PRNP were inoculated intracranially with 1% brain homogenate from a pig that had been intracranially inoculated with a pool of CWD from white-tailed deer. This pig developed neurological clinical signs, was euthanized at 64 months post-inoculation, and PrPSc was detected in the brain. Mice were monitored daily for clinical signs of disease until the end of the study. Mice were considered positive if PrPSc was detected in the brain using an enzyme immunoassay (EIA). In transgenic mice expressing porcine prion protein the average incubation period was 167 days post-inoculation (dpi) and 3/27 mice were EIA positive (attack rate = 11%). All 3 mice were found dead and clinical signs were not noted prior to death. One transgenic mouse expressing bovine prion protein was euthanized due to excessive scratching at 617 dpi and 2 mice culled at the end of the study at 700 dpi were EIA positive resulting in an overall attack rate of 3/16 (19%). None of the transgenic mice expressing human prion protein that died or were euthanized up to 769 dpi were EIA positive and at study end point at 800 dpi 2 mice had positive EIA results (overall attack rate = 2/20 = 10%). The EIA optical density (OD) readings for all positive mice were at the lower end of the reference range (positive mice range, OD = 0.266-0.438; test positive reference range, OD = 0.250-4.000). To the authors’ knowledge, cervid-derived CWD isolates have not been successfully transmitted to transgenic mice expressing human prion protein. The successful transmission of pig-passaged CWD to Tg40 mice reported here suggests that passage of the CWD agent through pigs results in a change of the transmission characteristics which reduces the transmission barrier of Tg40 mice to the CWD agent. If this biological behavior is recapitulated in the original host species, passage of the CWD agent through pigs could potentially lead to increased pathogenicity of the CWD agent in humans.


cwd scrapie pigs oral routes

***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <*** 

 >*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <*** 

***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). 

***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. 

This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. 

Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains. 




Friday, December 14, 2012

DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012

snip.....

In the USA, under the Food and Drug Administration's BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law.

Animals considered at high risk for CWD include:

1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and

2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.

Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.

The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.

Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.

There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.

snip.....

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011).

The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE).

Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.

snip.....

The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).

snip.....

In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.

snip.....

In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.

snip.....

Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.

snip.....


the feds just released this statement and you should read this very carefully about the mad cow feed ban that never was, and still isn't, and why this is so important, since USDA APHIS ARS Scientist recent transmitted Chronic Wasting Disease CWD TSE Prion, BY ORAL ROUTES, to PIGS AND SHEEP. this is terrible news, and proves the mad cow feed ban never worked, especially since it really never existed;

ponder this; ***> Adriano Aguzzi...''We even showed that a prion AEROSOL will infect 100% of mice within 10 seconds of exposure''

SUNDAY, SEPTEMBER 1, 2019 

FDA Reports on VFD Compliance

Before and after the current Veterinary Feed Directive (VFD) rules took full effect in January, 2017, the FDA focused primarily on education and outreach to help feed mills, veterinarians and producers understand and comply with the requirements. Since then, FDA has gradually increased the number of VFD inspections and initiated enforcement actions when necessary.


***> Wednesday, January 23, 2019 

***> CFIA SFCR Guidance on Specified risk material (SRM) came into force on January 15, 2019 <***


THURSDAY, JULY 20, 2017 

USDA OIE Alabama Atypical L-type BASE Bovine Spongiform Encephalopathy BSE animal feeds for ruminants rule, 21 CFR 589.200


WEDNESDAY, APRIL 24, 2019 

***> USDA Announces Atypical Bovine Spongiform Encephalopathy Detection Aug 29, 2018 A Review of Science 2019 <***


MONDAY, JANUARY 09, 2017 

Oral Transmission of L-Type Bovine Spongiform Encephalopathy Agent among Cattle 

CDC Volume 23, Number 2—February 2017 

*** Consumption of L-BSE–contaminated feed may pose a risk for oral transmission of the disease agent to cattle.

*** Consumption of L-BSE–contaminated feed may pose a risk for oral transmission of the disease agent to cattle.


TUESDAY, AUGUST 28, 2018 

USDA finds BSE infection in Florida cow 08/28/18 6:43 PM


WEDNESDAY, AUGUST 29, 2018 

USDA Announces Atypical Bovine Spongiform Encephalopathy Detection USDA 08/29/2018 10:00 AM EDT


WEDNESDAY, AUGUST 29, 2018 

Transmissible Spongiform Encephalopathy TSE Prion Atypical BSE Confirmed Florida Update USA August 28, 2018


***> P.108: Successful oral challenge of adult cattle with classical BSE

Sandor Dudas1,*, Kristina Santiago-Mateo1, Tammy Pickles1, Catherine Graham2, and Stefanie Czub1 1Canadian Food Inspection Agency; NCAD Lethbridge; Lethbridge, Alberta, Canada; 2Nova Scotia Department of Agriculture; Pathology Laboratory; Truro, Nova Scotia, Canada

Classical Bovine spongiform encephalopathy (C-type BSE) is a feed- and food-borne fatal neurological disease which can be orally transmitted to cattle and humans. Due to the presence of contaminated milk replacer, it is generally assumed that cattle become infected early in life as calves and then succumb to disease as adults. Here we challenged three 14 months old cattle per-orally with 100 grams of C-type BSE brain to investigate age-related susceptibility or resistance. During incubation, the animals were sampled monthly for blood and feces and subjected to standardized testing to identify changes related to neurological disease. At 53 months post exposure, progressive signs of central nervous system disease were observed in these 3 animals, and they were euthanized. Two of the C-BSE animals tested strongly positive using standard BSE rapid tests, however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not detected using rapid tests for BSE. Subsequent testing resulted in the detection of pathologic lesion in unusual brain location and PrPsc detection by PMCA only. 

***Our study demonstrates susceptibility of adult cattle to oral transmission of classical BSE. 

We are further examining explanations for the unusual disease presentation in the third challenged animal.


***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.

P.86: Estimating the risk of transmission of BSE and scrapie to ruminants and humans by protein misfolding cyclic amplification

Morikazu Imamura, Naoko Tabeta, Yoshifumi Iwamaru, and Yuichi Murayama

National Institute of Animal Health; Tsukuba, Japan

To assess the risk of the transmission of ruminant prions to ruminants and humans at the molecular level, we investigated the ability of abnormal prion protein (PrPSc) of typical and atypical BSEs (L-type and H-type) and typical scrapie to convert normal prion protein (PrPC) from bovine, ovine, and human to proteinase K-resistant PrPSc-like form (PrPres) using serial protein misfolding cyclic amplification (PMCA).

Six rounds of serial PMCA was performed using 10% brain homogenates from transgenic mice expressing bovine, ovine or human PrPC in combination with PrPSc seed from typical and atypical BSE- or typical scrapie-infected brain homogenates from native host species. In the conventional PMCA, the conversion of PrPC to PrPres was observed only when the species of PrPC source and PrPSc seed matched. However, in the PMCA with supplements (digitonin, synthetic polyA and heparin), both bovine and ovine PrPC were converted by PrPSc from all tested prion strains. On the other hand, human PrPC was converted by PrPSc from typical and H-type BSE in this PMCA condition.

Although these results were not compatible with the previous reports describing the lack of transmissibility of H-type BSE to ovine and human transgenic mice, our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.

 
***> why do we not want to do TSE transmission studies on chimpanzees $

5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. 

***> I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. 

***> Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

snip...

R. BRADLEY


WEDNESDAY, JUNE 10, 2020 

Radical Change in Zoonotic Abilities of Atypical BSE Prion Strains as Evidenced by Crossing of Sheep Species Barrier in Transgenic Mice


''Why is USDA "only" testing 25,000 samples a year? 

TUESDAY, AUGUST 18, 2020 

Sheep Scrapie, Bovine BSE, Cervid CWD, ZOONOSIS, TSE Prion Roundup August 18, 2020 


FRIDAY, AUGUST 7, 2020 

National List of Reportable Animal Diseases (NLRAD) proposed rule CWD, Scrapie, BSE, TSE, Prion Disease Singeltary Submission Docket APHIS-2017-0002


-----Original Message-----
From: Terry Singeltary <flounder9@verizon.net>
To: 
Sent: Tue, Sep 22, 2020 11:06 am
Subject: APHIS USDA MORE SCRAPIE ATYPICAL Nor-98 Confirmed USA September 15 2020

Program Summary

Performance Measures – The percent of cull black-faced sheep found positive at slaughter (Chart 1) and the percent of cull sheep found positive at slaughter and adjusted for face color1

(Chart 2) remains at 0 percent. The retrospective 6-month rolling average of the percent positive, black-faced sheep sampled at RSSS collection sites has been 0 since June 2016.

Scrapie Testing Results2 – Nor98-like scrapie was confirmed in 2 sheep sampled at slaughter in May 2020 and August 2020. In October 2019, lymph node tissue collected from a lamb at slaughter had suspect staining on IHC. Genotype of the lamb was AA at codon 136 and RR at codon 171, which is considered to be resistant to classical scrapie. Additional testing, using three alternative antibodies to scrapie, produced mixed results. Due to the unusual staining, results for this animal were reported as ‘inconclusive’ for classical scrapie. Further testing was conducted on the flock which was depopulated for diagnostic purposes and all samples were not detected by IHC. This case has similar staining to an RR lamb tested in April 2018.

1White, black and mottled-faced color sheep are weighted based on population; white-faced sheep have the greatest weight. If a white-faced positive sheep is found, this statistic will markedly increase. See notes below. 2Samples collected between October 1, 2019 and August 31, 2020, and confirmed by September 15, 2020.

SNIP...

Components of Scrapie Surveillance

• Regulatory Scrapie Slaughter Surveillance (RSSS) started April 1, 2003. It is a targeted slaughter surveillance program which is designed to identify infected flocks. Samples have been collected from 664,462 animals since April 1, 2003. As of August 31, 2020, 29,680 samples have been collected in FY 2020, 23,524 from sheep and 6,156 from goats. There have been 488 NVSL confirmed positive animals (473 classical cases – 470 sheep and 3 goats) and 16 Nor98-like cases since the beginning of RSSS. No animals have tested positive for classical scrapie in FY 2020.


Microb Risk Anal . 2020 Aug 15;100134. doi: 10.1016/j.mran.2020.100134. Online ahead of print. 

Assessing the aggregated probability of entry of a novel prion disease agent into the United Kingdom 

Verity Horigan 1, Paul Gale 1, Amie Adkin 1, Timm Konold 2, Claire Cassar 2, John Spiropoulos 2, Louise Kelly 1 3 Affiliations expand PMID: 32837979 PMCID: PMC7428426 DOI: 10.1016/j.mran.2020.100134 

Free PMC article 

Abstract 

In 2018 prion disease was detected in camels at an abattoir in Algeria for the first time. The emergence of prion disease in this species made it prudent to assess the probability of entry of the pathogen into the United Kingdom (UK) from this region. Potentially contaminated products were identified as evidenced by other prion diseases. The aggregated probability of entry of the pathogen was estimated as very high and high for legal milk and cheese imports respectively and very high, high and high for illegal meat, milk and cheese products respectively. This aggregated probability represents a qualitative assessment of the probability of one or more entry events per year into the UK; it gives no indication of the number of entry events per year. The uncertainty associated with these estimates was high due to the unknown variation in prevalence of infection in camels and an uncertain number and type of illegal products entering the UK. Potential public health implications of this pathogen are unknown although there is currently no evidence of zoonotic transmission of prion diseases other than bovine spongiform encephalopathy to humans.

Keywords: Aggregated probability; Entry assessment; Prion agent.

Crown Copyright © 2020 Published by Elsevier B.V. All rights reserved.

Conflict of interest statement None.

1. Introduction

Prion diseases, or transmissible spongiform encephalopathies (TSEs), are progressive neurodegenerative disorders that affect both humans and animals and are characterised by long incubation periods frequently of many years. Such disorders are biochemically characterised by conversion of a normal cellular form of the prion protein (PrPc ) into a misfolded disease associated form (PrPSc) that accumulates into amyloid protein aggregates in the brain (Norrby, 2011).

Scrapie in sheep was the first animal TSE to be described in the 18th century in Great Britain but TSEs have since been detected in a number of species, including scrapie in goats, chronic wasting disease (CWD) in deer and bovine spongiform encephalopathy (BSE) in cattle. The BSE crisis led to the slaughter of 3.3 million cattle and an estimated economic loss of £3.7 billion in the United Kingdom (UK) (Beck et al., 2007). It is believed that BSE crossed the species barrier to humans through the consumption of contaminated beef and bovine products during the 1990s (ECDC 2017) and that this zoonotic transmission of BSE has since led to the death of 178 people with variant CreutzfeldtJakob disease (NCJDRSU 2019). Prion diseases can therefore pose serious risks to both animal and human health and the first detection of a TSE in deer in Europe in 2016 demonstrates the continued need for a global awareness of these diseases (Benestad et al., 2016).

Within the European Union there is a statutory requirement to test for TSEs where disease is suspected and active surveillance systems to test for disease in healthy slaughter animals or fallen stock. However, in countries that do not have active surveillance systems, detection of cases relies on the reporting of clinical suspects where, if the animal keeper or veterinary surgeon are not familiar with the clinical signs, TSEs may not be considered in the differential diagnosis of neurological diseases or other conditions that present with similar signs (Konold and Phelan, 2014). Prion disease has recently been confirmed in three dromedary camels (Camelus dromedarius) from an Algerian slaughterhouse (Babelhadj et al., 2018) after clinical signs compatible with those of TSEs in other species were observed ante mortem. Disease associated pathological changes or prion protein were found in brain by Western blotting, histology, immunohistochemistry (IHC) and paraffin-embedded tissue blot; PrPSc was also detected in the lymph nodes of the one camel tested by IHC.

Information gathered from breeders and slaughterhouse personnel suggests that similar clinical signs had been observed since the 1980s (Babelhadj et al., 2018). Subsequently, the disease has also been reported in a single case of a 12 year old dromedary camel from the region of Tataouine, Tunisia (Agrimi, 2019; OIE bulletin 2019). 

There are many knowledge gaps about the biological characteristics of this new TSE, termed camel prion disease (CPD). Detection of infection in lymph nodes of one animal suggests extra-neural pathogenesis and, therefore, potential transmission of CPD between animals similar to that of classical scrapie and CWD. Such transmission of CPD could be facilitated over long distances by the traditional nomadic herding practices of dromedaries and the trade patterns between Algeria and other countries in North Africa and the Middle East (Bouslikhane, 2015). In light of the devastation caused by BSE, and its subsequent zoonotic transmission, CPD was used here to assess the probability of entry of a novel prion disease agent into the UK via livestock and livestock products. The approach used was to assess the aggregated probability, using the number of imports per year to avoid potential under-estimation as has previously been described (Kelly et al., 2018). Of note, the zoonotic potential of the disease is unknown and this assessment is of the probability of introduction of the CPD agent into the UK only, not of any onward transmission to humans or animals. 

2. Methods

2.1. Risk question and pathway

The risk question to be addressed was:

‘What is the aggregated probability of entry of the CPD agent into the United Kingdom from North Africa or the Middle East in one year?’

The risk pathway highlighting the probabilities to be considered for potential entry of the CPD agent into the UK is shown in Fig. 1.

The approach used was qualitative and based on the framework set out by the OIE (World Organization for Animal Health) (OIE 2004). The probabilities in Fig. 1 are conditional and were expressed qualitatively as negligible, very low, low, medium, high and very high (EFSA 2006; FAO/ WHO 2009). The qualitative probabilities for each stage of the risk pathway up to, and including, the probability that an infected animal/ animal product is not detected at import (p1, p2, p3, p4, p5) were combined as described previously (Gale et al., 2010) to give the probability of entry of an individual infected animal/product (P). Entry was defined as the probability of entry of a CPD positive animal or contaminated animal product into the UK within one year taking into account the current products which are imported from the regions of interest. For comparison, an aggregated probability of entry (Pa) of all categories of live animals/products was also assessed to provide an annual probability of entry using a graphical reference tool proposed by Kelly et al., (2018). This tool removes some of the subjectivity that is often associated with deriving the annual qualitative probability of entry for animal import risk assessments as it enables the number of units imported to be combined with this individual qualitative event probability. In this way, the reference tool ‘considers various qualitative categories of individual probability and determines the relationship between these probabilities, the number of imports and the annual probability of entry’ (Kelly et al., 2018).

The quantitative bounds for the individual probability correspond to previously published example definitions (FAO/WHO 2009) (Table 1).

Uncertainty associated with the estimates for the probabilities were categorised according to Spiegelhalter and Riesch (2011) depending on availability, completeness and quality of evidence.

Relevant data for use in the risk assessment were scarce. Briefly, the number of camel products imported into the UK from the area of interest was obtained from the EU Trade Control and Expert System (TRACES) where available. Otherwise, the following assumptions were made:

■ The prevalence of CPD in camels in the region of interest - 3.1% (based on Babelhadj et al. (2018))

■ The incidence and prevalence of CPD in camel products, derived from: 

Fig. 1.. Risk pathway for the aggregated probability of entry of the CPD agent into the UK in one year. 

Table 1 Definitions of the quantitative bounds used to correspond to the qualitative probability (taken from (Chianini et al., 2015)). 

snip...

○ Disease progression in camels – similar to scrapie (based on Babelhadj et al. (2018))

○ Relative resistance of CPD associated PrPSc to heat and chemicals – similar to other TSEs (see Results section for references)

○ Correlation of disease presence and PrPSc deposition – similar to other TSEs (see Results section for references)

○ Systemic distribution of disease – similar to scrapie (based on Babelhadj et al. (2018))

■ The number of illegally imported products – based on data on illegal seizures and FAOSTAT production data

■ The number of processed camel products both legally and illegally imported – assumed by the author 

A further assumption made was that the aggregated probability calculations used the same quantitative bounds (FAO/WHO 2009) as used in the tool by Kelly et al. (2018). It is acknowledged that this probability could therefore change if these bounds were to be altered. 

3. Results

3.1. Risk assessment

3.1.1. Probability camel is infected with camel prion disease in exporting country (p1)

Detection of abnormal neurological signs since the 1980s within a restricted geographical area of Algeria suggests that the expansion of CPD to other areas (and countries) may be restricted or that the disease can remain largely undiagnosed. According to a recent presentation of the Mediterranean Animal Health Network, the disease was also reported in Tunisia and the incidence in the initial region of Algeria was described as ‘rapidly and progressively increasing’ (Agrimi, 2019). It is, therefore, possible that movement of camels has allowed infected animals to enter other countries. Asides from the legal trade of camels, approximately 268 million people in Africa practice some form of pastoralism (Luizza, 2017). For example, over 95% of cross-border trade within the Horn of Africa is unofficial and carried out by nomadic pastoralists trading livestock. Given that disease was first noticed in the 1980s and the nomadic way of life in this area, exporting countries were therefore considered as those making up the regions of North Africa and the Middle East for the purpose of this assessment.

Twenty of 937 camels in 2015 and 51 of 1,322 in 2016 showed neurologic signs at slaughter giving an overall estimated apparent prevalence of 3.1% in dromedaries brought for slaughter (Babelhadj et al., 2018). In the absence of further information including confirmatory testing, an assumption was made that the prevalence of CPD in live camels in the regions of interest was high with high uncertainty because of the lack of testing data from countries other than Algeria and in only 3 camels in Algeria itself.

3.1.2. Probability infected animal is not detected on farm or at slaughter (p2)

Although anecdotal evidence suggests that herdsmen have noticed neurological signs in camels on the farm and at slaughter (Babelhadj et al., 2018) it was assumed that these animals were still being sent for slaughter and entering the food and feed chains. It was also assumed that as the other countries in the regions of interest have not been aware of the presence of this disease that they would not be surveying their animals for clinical signs and therefore animals will still be sent to slaughter. The probability of a camel with CPD not being detected on farm or at slaughter was therefore assumed to be high with low uncertainty.

3.1.3. Probability animal or animal product for export contains the CPD agent given the camel is infected and undetected (p3)

Camel products that can be legally exported to the UK, those for which databases exist to monitor the levels of exports and the probability of containing the CPD agent (given the source camel is infected) of these products are shown in Table 2.

The probability of a commodity containing the CPD agent depends on the presence of infectivity in the live animal and processes the commodity has undergone which may destroy it. As such, the uncertainty associated with this probability for all products was high as a result of knowledge gaps concerning these two factors.

The prion protein, PrPSc, has been shown to accumulate with infectivity and is therefore considered a reliable biochemical marker for infection (Thomzig et al., 2007). PrPSc has been isolated from the muscle tissue, skin, milk and urine of TSE affected animals (Andréoletti et al., 2004; Thomzig et al., 2007; Andréoletti et al., 2011; Buschmann and Groschup, 2005; Chianini et al., 2015; 

Table 2

Probability of containing the CPD agent for individual commodities originating from camels including primary and processed products.

Commodity Primary product used Import to the UK allowed from regions of interest

Traceable (source) Probability of containing the CPD agent (uncertainty in brackets)

Live animals

Live camels - No - Certain

Primary products

Meat - No - High (high)

Milk - Yes Yes (Traces) High (high)

Hair - Yes Yes (Traces) Negligible (high)

Urine - No - High (high)

Semen - No - Low (high)

Treated Hides and skins - Yes Yes (Traces) High (high)

Processed products

Soap Milk Yes No Negligible (high)

Lip balm Milk Yes No Negligible (high)

Chocolate Milk Yes No Negligible (high)

Leather products Skin Yes No Very low (high)

Cheese Milk Yes Yes (Traces) High (high)

Bone ornaments Bone Yes No Very low (high) 

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Henderson et al., 2015; Konold et al., 2013; Rubenstein et al., 2011) and the pessimistic assumption here is that CPD distribution in a camel is similar to classical scrapie and CWD based on the detection of PrPSc in the lymphatic system (Babelhadj et al., 2018; Haley et al., 2014). It was, therefore, estimated that the probability that a camel meat/milk/urine product contains the CPD agent, given it comes from an infected, undetected animal was high.

The only milk imported from the region of interest to the UK is Ultra-High temperature treated (UHT). This processing involves heating to ∼135-145°C for 1-10 seconds (Deeth, 2004) which is not sufficient to fully destroy prion activity (Franscini et al., 2006; Yoshioka et al., 2013). Similarly for hides/skins, if they are not treated with a transformation process with a proven capacity to reduce TSE infectivity (Scientific Steering Committee 2000), then it is considered unlikely that the CPD agent would be destroyed. The probability of UHT milk and hides/skins containing the CPD agent, was therefore estimated as high.

The European Food Safety Authority (EFSA) considered the risk of TSE transmission associated with semen and embryos collected from classical scrapie incubating sheep and goats to range from negligible to low (EFSA Panel on Biological Hazards (BIOHAZ) 2010). PrPSc in semen from a scrapie affected ram has been reported (Rubenstein et al., 2012) so the probability of semen from infected undetected camels containing the CPD agent was estimated to be low (worst case assumption based on the EFSA opinion). For hair PrPSc has been detected in the fibres of the follicular neural network and in the hair follicle isthmus in hamsters but not in the outer root sheet cells or the bulb region (Thomzig et al., 2007). The probability of camel hair being infected with the CPD agent was therefore assumed to be negligible given the lack of evidence for PrPSc in the cells of the hair.

Soap products are described as containing ∼ 25% raw camel milk and use a saponifying agent which starts the process of turning the raw ingredients into soap. This agent is usually 100% sodium hydroxide which is known to inactivate PrPSc at a concentration of 0.1M (Käsermann and Kempf, 2003). The probability of soap products and lip balm retaining the CPD agent was therefore estimated to be negligible. Chocolate products manufactured using camel milk can contain ∼ 21% pure camel milk powder. Milk powder production involves spray drying milk in a flow of hot air between 180°C to 220°C (Consulting, W.D. 2019), sufficient to destroy prion activity (Somerville and Gentles, 2011). The probability of chocolate being infected with the CPD agent was thus estimated to be negligible. Camel milk does not curdle readily so camel cheese is traditionally consumed in fresh or fermented form. Fermentation is not expected to reduce the levels of infectivity so the probability of cheese from infected undetected animals being infected with the CPD agent was estimated to be high.

Products made from treated skins/hides from infected animals are assumed to have undergone a tanning process whereby the use of strong alkali and acid solutions will reduce the level of TSE infectivity (Appel et al., 2006; Hughson et al., 2016; Käsermann and Kempf, 2003). The probability of infection was therefore assumed to be very low. Similarly, although experimental evidence has demonstrated TSE infectivity in bone marrow (Huor et al., 2017; Seelig et al., 2010), during the process of cleaning bones for use in processed products such as jewellery it is assumed that the bone marrow is removed. The probability of camel bones being infected with the CPD agent, given an animal is infected, was therefore assumed to be very low.

3.1.4. Probability prion in live animal or animal product survives journey to the UK (p4) and is not detected at import (p5)

The probability of prions remaining infectious throughout the journey to the UK was assumed to be high with low uncertainty for all products for both legal and illegal routes due to the characteristic resistance of PrPSc to both chemical and physical degradation (Taylor, 1999) and evidence of its long term survival (Brown and Gajdusek, 1991; Georgsson et al., 2006). There are no gross lesions suggestive of TSE infection in animal products. There are also no post import tests for TSEs in either legal milk imports or illegal seizures. The probability of CPD infectivity not being detected on import to the UK was therefore assumed to be high with low uncertainty for all products for both legal and illegal routes. Additionally, the annual proportion of searched luggage among the total number of passengers entering a European country (Switzerland) has been estimated at between 0.06% and 0.24% (Jansen et al., 2016). If this is applied to the UK then it suggests that the probability of an illegally imported infected animal product not being detected at import is high.

The probability of CPD not being detected in a live animal was considered to be medium as detection will depend on several factors including the animal showing clinical signs of TSE infection and the signs being correctly diagnosed as TSE by the veterinary inspector. The age of the animal and the progression of clinical disease will also be relevant. The uncertainty associated with this estimate was low.

3.1.5. Probability of entry of the CPD agent in an individual animal/ product into the UK (P)

The probability of entry of the CPD agent in an individual animal/ product into the UK was calculated by combining the probabilities in the risk pathway as described previously (Gale et al., 2010). Results are summarised in Table 3 for both legal and illegal routes of entry for live animals and products.

3.1.6. Number of units imported into the UK per year (n)

Legal exports of live camels, camel meat (including untreated hides), urine and semen from the regions of interest to the UK are prohibited (Table 2). There were no imports of treated hides from camels from the region of interest recorded for the period 2010 to 2016 but, as such imports are permitted, the number of treated hides being exported to the UK was estimated to be within the range of 0 - 1. Since 2010 there has only been one possible consignment of ‘hair’ of species ‘other’ so may not have been of camel origin but an estimate of 1 unit was used here.

The Traces database has details of the volumes of milk and milk products imported into the UK. Approximately 10,830 kg of UHT milk products (it is assumed that the average product is 1 litre in size or 1 kg in weight giving a total of 10,830 units) and 11 Kg (equivalent to 22 units based on a 500g product) of cheese were exported to the UK in one year.

For processed products, soap, lip balm and milk chocolate made from camel milk are available in the UK via the internet or instore. Camel bone jewellery and ornaments and leather goods are also available for sale via the internet. It is assumed that these are all niche products with a limited market and the number of units of each product imported into the UK was estimated to be 1,000.

For illegal imports, data on illegal seizures were used to estimate the number of camel meat and dairy products illegally entering the UK. Illegal imports of red meat and dairy products are not categorised by species so, as a proxy for this, data (FAOSTAT) on the production of animals in the regions of interest were used to predict what percentage of each category would be a camel product. For 2016, camel meat contributed 4.7% to production of all red meat species and camel milk represented 0.47% of whole milk production (FAOSTAT) in the regions of interest. It is unknown whether the illegal milk/milk products seized would have undergone any heat treatment, but as stated above, UHT would not destroy infection. Using the illegal seizure data and FAOSTAT production data it was estimated that 242 units (200g products) of camel meat, 19 units (1Kg product) of milk and 20 units (500g product) of cheese illegally enter the UK in one year.

The number of illegal imports of treated skins/hides and hair was estimated to be between 0 -100 due to the size of the commodity and the low value placed on camel skins in the region of interest. The same figure was used for camel urine which has been used as a traditional medicine since ancient times (Abdel Gader and Alhaider, 2016) so it is possible that passengers entering the UK could illegally import camel urine for medicinal purposes. 

For semen, there are difficulties associated with the application of artificial insemination in camelids in particular the collection and handling of semen due to the viscous nature of the seminal plasma (Skidmore, 2018). Therefore the estimate for the number of illegal camel semen straws imported to the UK was between 1-10. The illegal import of batches of camel hair was also estimated to be between 1 - 10 due to the low value placed on camel hair in the region of interest.

The number of illegal imports of all processed products was esti - mated to be between 0 - 1000 assuming these are luxury products aimed at a niche export market.

3.1.7. Aggregated probability of entry of the CPD agent into the UK from North Africa or the Middle East per year (Pa)

The aggregated annual probability of entry of the CPD agent was estimated using the number of units of animals/products imported per year where known (or estimated by the authors where unknown) and the qualitatively assessed probability of entry for an individual infected product (Table 3) using the graphical framework described by Kelly et al., (2018).

For legal imports, the aggregated probability of entry was negligible for livestock, camel meat, urine and semen as these products are pro - hibited (Table 4). The probability was also negligible for hair, soap, lip balm and chocolate based on the assumed lack of infectivity in these products and the number of products imported. For cheese and UHT milk the probability of at least one infected unit entering the UK per year was high and very high respectively. The individual probability per unit for UHT milk increased from high to an aggregated probability of very high as a result of the number of units imported (>10

4

) in one year.

The number of units per product illegally imported to the UK was estimated by the authors due to lack of data. This resulted in a range of probabilities for some products, from negligible if no items were im - ported to very high if 100 products were imported (treated hides/skins, urine) (Table 5). Milk products and cheese both had a high probability of entry and camel meat had a very high probability based on the es - timated number of products imported. 

4. Discussion

This assessment used the example of CPD to address the probability of entry of a novel prion agent into the UK. The estimated probability per unit was aggregated to take into account the number of units of each product imported per year. Thus the predicted probability is the probability of entry of one or more (i.e. at least one) infected unit per year into the UK. The predicted aggregated probability for legal imports was highest for UHT milk products and cheese whilst for treated hides and skins it was estimated to range from negligible to high depending on whether any units were imported in one year. For illegally imported meat, milk and cheese products the aggregated probability of at least one entry event per year was estimated as very high, high and high respectively. If testing were to be carried out to negate the presence of CPD in the camel population used to produce milk legally exported to the UK then the annual probability of entry would be reduced to neg - ligible. Similarly, as the aggregated probability is based on an example of assumed quantitative bounds (FAO/WHO 2009), were these bounds to be changed then the aggregated probability could also change.

The estimates of probability are associated with high uncertainty throughout the risk pathway hinging, in particular, on the application of a blanket prevalence of CPD within the camel population. The Middle East Respiratory syndrome coronavirus (MERS-CoV) provides an example of an undetected pathogen in camels which, once identi - fied, has since been detected throughout much of the regions of interest suggesting that movement of camels has provided a route of incursion of the virus to different countries (Haagmans et al., 2014; Meyer et al., 2014; Reusken et al., 2013; Reusken et al., 2014). It is possible that

5

transmission of CPD between animals could have similarly been facilitated by movement of infected live animals although the disease has currently only been described in a restricted geographical area of Algeria and Tunisia. The involvement of lymphoid tissue, observed in both the Algeria and Tunisia cases, is suggestive of a peripheral pathogenesis, similar to scrapie and CWD in which horizontal transmission occurs efficiently under natural conditions (OIE bulletin 2019). The uncertainty is compounded by lack of data on the epidemiology of CPD. As of June 2020, there is no publically available up-to-date information with regards to the prevalence of CPD in the area of interest or whether additional cases have been detected. The OIE Scientific Commission has called for the collection of further scientific evidence in countries with dromedary camel populations to measure the impact of the disease (OIE bulletin 2019). This could influence the results of the risk assessment should an increase in the incidence of CPD have occurred.

The import of animal products in travellers’ personal consignments presents a considerable risk of introducing infectious agents (Simons et al., 2016; Falk et al., 2013; Hartnett et al., 2007). Analysis from a study on illegal seizures of airline passengers in Germany, found that seizures are typically local foodstuffs reflecting culturally enrooted consumption patterns. Camel milk and meat are esteemed in the regions of interest for their medicinal properties; camel meat is also frequently eaten on special occasions or for ritual celebrations (Jansen et al., 2016). It is, therefore, not unreasonable to assume that a proportion of illegal seizures of milk products and red meat originate from camels.

Significant knowledge gaps exist about prion disease in camels. Although PrPSc is believed to be the most useful marker of TSE disease identified to date, it has also been shown that its presence does not always directly correlate with infectious titres and that bioassay is still required for verification of infection (Chianini et al., 2015). So far, this has not been reported for CPD. The relative heat resistance of camel prions is also unknown, a factor which could affect the risk pathway if it were proven to show a greater susceptibility to heat than BSE or scrapie prions. Disease progression in CPD could also affect the risk pathway, specifically the prevalence of infection in camel products, if the slaughter age of most camels is young and disease is only detected in older animals. Likewise, products from animals with CPD but not yet showing clinical signs could also contribute to the probability of entry; this is particularly important regarding the long incubation period of the prion diseases. Further research to gain a better understanding into the CPD agent behaviour and improvement of the market traceability of camel products may alter the probability estimates stated here and should be considered in future risk assessments.

In conclusion, this paper assesses the annual probability of at least one entry event of camel products containing the CPD agent into the UK. The probability of entry from the Middle East or North Africa was considered to be highest from legal import of milk and cheese and the illegal import of camel meat, milk and cheese. These estimates are associated with high uncertainty due to the number of assumptions made throughout the risk pathway in particular the prevalence of CPD in camels, and of the CPD agent in camel products, and the number of products illegally entering the UK. However, this assessment does not consider the consequence of the exposure of uninfected animal populations to these products, only the probability of entry of the agent. Therefore, whilst a high probability of entry of the CPD agent has been estimated for some products, whether there is a subsequent probability of onward transmission is unknown (Fryer and McLean, 2011). The zoonotic potential of CPD is unknown but there is currently no evidence of zoonotic transmission of TSEs other than BSE to humans. Further research to look at the zoonotic potential and risks to public health would be beneficial.

Tables 3, 4, and 5 not shown here...tss

Ethics statement

The authors confirm that the ethical policies of the journal, as noted on the journal's author guidelines page, have been adhered to. No ethical approval was required as this is a risk assessment article with no original research data.’

Funding

“This work was funded by Defra, Scottish Government and Welsh Government through funding to the APHA Project ED1043 Enhancing surveillance, facilitating and improving outbreak response and informing policy” Declaration of Competing Interest

None.

References 


Camel prion disease: a possible emerging disease in dromedary camel populations?

The identification of a new prion disease in dromedary camels in Algeria and Tunisia, called camel prion disease (CPD), extends the spectrum of animal species naturally susceptible to prion diseases and opens up new research areas for investigation.

Camel prion disease was identified in 2018 in adult camels showing clinical signs at the ante mortem inspection at slaughterhouses in the region of Ouargla (Algeria), and in 2019 in the region of Tataouine (Tunisia). It adds to the group of existing animal prion diseases, including scrapie in sheep and goats, chronic wasting disease (CWD) in cervids and BSE (mainly in bovines). The detection of a new prion disease in the dromedary population requires attention and investigation needs to be carried out to assess the risks of this disease to animal and public health. As of today, very limited epidemiological information is available to assess the prevalence, geographical distribution and dynamic of the transmission of the disease.

Based on the clinical signs suggesting prion disease, CPD seems to have occurred in 3.1% of the dromedaries brought to the abattoir in Ouargla. Pathognomonic neurodegeneration and diseasespecific prion protein (PrPSc) were detected in brain tissue from three symptomatic animals (source: CDC article wwwnc.cdc.gov/eid/article/24/6/17-2007_article). 

In May 2019, the OIE received a report from Tunisia on a single case of a 12-year-old slaughtered dromedary camel showing neurological signs confirmed as CPD by the Istituto Superiore di Sanità (ISS) based in Italy.

©B. Babelhadj/University Kasdi Merbah, Algeria www.oiebulletin.com 2

Is camel prion disease transmissible in natural conditions?

The involvement of lymphoid tissue in prion replication, observed both in the Algeria and Tunisia cases, is suggestive of a peripheral pathogenesis, which is thought to be a prerequisite for prion shedding into the environment. As with other animal prion diseases, such as scrapie and CWD, in which lymphoid tissues are extensively involved and horizontal transmission occurs efficiently under natural conditions, the detection of prion proteins in lymph nodes is suggestive of the infectious nature of CPD and concurs to hypothesise the potential impact of CPD on animal health. No evidence is currently available with which to argue for the relevance of CPD for human health. However, no absolute species barrier exists in prion diseases and minimising the exposure of humans to prion-infected animal products is an essential aspect of public health protection. As for the relationship between CPD and other animal prion diseases, preliminary analyses suggest that CPD prions have a different molecular signature from scrapie and BSE.

Actions on the follow up of CPD

Since the first description of CPD, the OIE promoted discussions on the impact of this new disease through the OIE Scientific Commission for Animal Diseases (Scientific Commission). The Scientific Commission consulted two OIE ad hoc Groups, one on BSE risk status evaluation of Members and the other on camelids. It analysed the information available from the Algeria and Tunisia cases to evaluate if CPD should be considered an ‘emerging disease’ based on the criteria listed in the Terrestrial Animal Health Code1

. The OIE Scientific Commission noted that limited surveillance data were available on the prevalence of CPD and that the evidence was not sufficient to measure, at that time, the impact of the disease on animal or public health. Therefore, it was concluded that, with the current knowledge, CPD did not currently meet the criteria to be considered an emerging disease. Nonetheless, it was emphasised that CPD should be considered as a new disease not to be overlooked and called for the collection of further scientific evidence through research and surveillance in the affected countries and in countries with dromedary camel populations to measure the impact of the disease. As new scientific evidence becomes available,the OIE Scientific Commission will reassess whether this disease should be considered as an emerging disease.

The worldwide camel population is ~35 million head (FAO, 2019), 88% of which is found in Africa. The camel farming system is evolving rapidly, and these animals represent vital sources of meat, milk and transportation for millions of people living in the most arid regions of the world. This makes it necessary to assess the risk for animal and human health and to develop evidence-based policies to control and limit the spread of the disease in animals, and to minimise human exposure. As a first step, the awareness of Veterinary Services about CPD and its diagnostic capacity needs to be improved in all countries where dromedaries are part of the domestic livestock.

At the regional level, CPD was first discussed in the 18th Joint Permanent Committee of the Mediterranean Animal Health Network (REMESA) held in Cairo, Egypt, in June 2019 where an expert 1 a new occurrence in an animal of a disease, infection or infestation, causing a significant impact on animal or public health resulting from a) a change of a known pathogenic agent or its spread to a new geographic area or species, or b) a previously unrecognised pathogenic agent or disease diagnosed for the first time www.oiebulletin.com

3

from ISS, Italy, shared the knowledge available on the new disease with the 15 REMESA Member Countries. The discussion highlighted the need to strengthen surveillance systems in order to collect epidemiological data to inform the risk assessments. The results of these risk assessments will support the implementation of evidence-based policies to manage the risks in both animals and humans.

CPD was recently discussed at the 15thConference of the OIE Regional Commission for the Middle East in November. During this conference, the CAMENET (Camel Middle East Network) launched a wideranging proposal for training, coordinated surveillance and research on CPD. In addition, the ERFAN (Enhancing Research forAfrica Network), a platform aimed at enhancing scientific cooperation between Africa and Italy, during its 2nd ERFAN meeting for North Africa, presented a project on CPD with the objective of increasing CPD coordinated surveillance in North Africa.

The OIE, through its Reference Laboratories for prion diseases, and by involving the above scientific initiatives, is keeping a close watch on the evolution of the disease to gather scientific evidence and to allow a proper and more thorough assessment of the risk associated with this novel disease.

◼ December 2019


Monday, September 14, 2020 

Assessing the aggregated probability of entry of a novel prion disease agent into the United Kingdom


Tuesday, September 15, 2020 

Mad Camel Disease CPD TSE Prion dromedary camels (Camelus dromedarius) is spreading


THURSDAY, AUGUST 06, 2020 

Scrapie Documented in Tunisia


Thursday, August 1, 2019 

Camel prion disease detected in Tunisian camels Camel prion disease detected in Tunisian camels

A novel prion disease first reported in three dromedary camels in Algeria in 2018 has now been detected in dromedaries in Tunisia, the second country to be affected within a year, ProMED Mail, the online reporting system of the International Society for Infectious Diseases, reported yesterday.

The Tunisian detection and the latest information about the disease, called camel prion disease (CPD) and sometimes referred to as "mad camel disease", came from a presentation at the Mediterranean Animal Health Network meeting, held in Cairo on Jun 26 and 27. According to the meeting presentation, CPD is spreading rapidly in the Ouargla region of Algeria where the disease was first identified in older camels at a slaughterhouse.

The scientists who presented at the meeting also said preliminary results suggest that the CPD prion is different from scrapie and bovine spongiform encephalitis (BSE, or "mad cow disease").

A comment from the ProMED Mail moderator Arnon Shimshony, DVM, associate professor of veterinary medicine at Hebrew University of Jerusalem, notes that the area where CPD was first found in Algeria is about 174 miles from the Tunisian border.

In the initial report on the first detection in Algerian camels, published in April 2018 in Emerging Infectious Diseases, described disease-specific prion protein in brain tissues from symptomatic camels, including positive samples in lymph nodes, suggesting infection. The moderator also requested more details about the detections in Tunisia, including location, clinical signs, and ages and origins of affected camels. Jul 29 ProMED Mail post Apr 18, 2018, CIDRAP News story "'Mad camel' disease? New prion infection causes alarm"



***> NEW TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION DISEASE (MAD CAMEL DISEASE) IN A NEW SPECIES <***

NEW OUTBREAK OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION DISEASE IN A NEW SPECIES

Subject: Prion Disease in Dromedary Camels, Algeria

Our identification of this prion disease in a geographically widespread livestock species requires urgent enforcement of surveillance and assessment of the potential risks to human and animal health.



Wednesday, May 30, 2018 

Dromedary camels in northern Africa have a neurodegenerative prion disease that may have originated decades ago


***> IMPORTS AND EXPORTS <***

***> SEE MASSIVE AMOUNTS OF BANNED ANIMAL PROTEIN AKA MAD COW FEED IN COMMERCE USA DECADES AFTER POST BAN

Saturday, April 14, 2018

Dromedary Camels Algeria Prion (Mad Camel Disease) TSE BSE MRR Import Export Risk Factors Excluding Grains and Plants

Dromedary Camels Algeria Prion (Mad Camel Disease) TSE BSE MRR Import Export Risk Factors Excluding Grains and Plants

(Grains and Plants Materials Could Harbor the Transmissible Spongiform Encephalopathy TSE Prion agent...TSS)

Dromedary Camels Algeria Prion (Mad Camel Disease) TSE BSE MRR Import Export Risk Factors Excluding Grains and Plants



America BSE 589.2001 FEED REGULATIONS, BSE SURVEILLANCE, BSE TESTING, and CJD TSE Prion

so far, we have been lucky. to date, with the science at hand, no cwd transmitted to cattle, that has been documented, TO DATE, WITH THE SCIENCE AT HAND, it's not to say it has not already happened, just like with zoonosis of cwd i.e. molecular transmission studies have shown that cwd transmission to humans would look like sporadic cjd, NOT nvCJD or what they call now vCJD. the other thing is virulence and or horizontal transmission. this is very concerning with the recent fact of what seems to be a large outbreak of a new tse prion disease in camels in Africa. there is much concern now with hay, straw, grains, and such, with the cwd tse prion endemic countries USA, Canada. what is of greatest concern is the different strains of cwd, and the virulence there from? this thing (cwd) keeps mutating to different strains, and to different species, the bigger the chance of one of these strains that WILL TRANSMIT TO CATTLE OR HUMANS, and that it is documented (i believe both has already occured imo with scienct to date). with that said, a few things to ponder, and i am still very concerned with, the animal feed. we now know from transmission studies that cwd and scrapie will transmit to pigs by oral routes. the atypical bse strains will transmit by oral routes. i don't mean to keep kicking a mad cow, just look at the science; 

***> cattle, pigs, sheep, cwd, tse, prion, oh my! 

***> In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). 

Sheep and cattle may be exposed to CWD via common grazing areas with affected deer but so far, appear to be poorly susceptible to mule deer CWD (Sigurdson, 2008). In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). It is not known how susceptible humans are to CWD but given that the prion can be present in muscle, it is likely that humans have been exposed to the agent via consumption of venison (Sigurdson, 2008). Initial experimental research suggests that human susceptibility to CWD is low and there may be a robust species barrier for CWD transmission to humans (Sigurdson, 2008), however the risk appetite for a public health threat may still find this level unacceptable. 



cwd scrapie pigs oral routes 

***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <*** 

>*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <*** 

***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). 

***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains. 




Friday, December 14, 2012 

DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012 

snip..... 

In the USA, under the Food and Drug Administration's BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law. Animals considered at high risk for CWD include: 

1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and 

2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal. 

Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants. 

The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. 

It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011. 

Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB. 

There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products. 

snip..... 

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011). The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE). Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison. snip..... The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008). 

snip..... 

In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion. snip..... In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates. 

snip..... 

Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents. 

snip..... 


***> READ THIS VERY, VERY, CAREFULLY, AUGUST 1997 MAD COW FEED BAN WAS A SHAM, AS I HAVE STATED SINCE 1997! 3 FAILSAFES THE FDA ET AL PREACHED AS IF IT WERE THE GOSPEL, IN TERMS OF MAD COW BSE DISEASE IN USA, AND WHY IT IS/WAS/NOT A PROBLEM FOR THE USA, and those are; 

BSE TESTING (failed terribly and proven to be a sham) 

BSE SURVEILLANCE (failed terribly and proven to be a sham) 

BSE 589.2001 FEED REGULATIONS (another colossal failure, and proven to be a sham) 

these are facts folks. trump et al just admitted it with the feed ban. 

see; 

FDA Reports on VFD Compliance 

John Maday 

August 30, 2019 09:46 AM VFD-Form 007 (640x427) 

Before and after the current Veterinary Feed Directive rules took full effect in January, 2017, the FDA focused primarily on education and outreach. ( John Maday ) Before and after the current Veterinary Feed Directive (VFD) rules took full effect in January, 2017, the FDA focused primarily on education and outreach to help feed mills, veterinarians and producers understand and comply with the requirements. Since then, FDA has gradually increased the number of VFD inspections and initiated enforcement actions when necessary. On August 29, FDA released its first report on inspection and compliance activities. The report, titled “Summary Assessment of Veterinary Feed Directive Compliance Activities Conducted in Fiscal Years 2016 – 2018,” is available online.


SUNDAY, SEPTEMBER 1, 2019 

***> FDA Reports on VFD Compliance 


''Why is USDA "only" testing 25,000 samples a year? 

TUESDAY, AUGUST 18, 2020 

Sheep Scrapie, Bovine BSE, Cervid CWD, ZOONOSIS, TSE Prion Roundup August 18, 2020 


MONDAY, AUGUST 24, 2020 

Very low oral exposure to prions of brain or saliva origin can transmit chronic wasting disease


FRIDAY, AUGUST 7, 2020 

National List of Reportable Animal Diseases (NLRAD) proposed rule CWD, Scrapie, BSE, TSE, Prion Disease Singeltary Submission Docket APHIS-2017-0002




-----Original Message-----
From: Terry Singeltary <flounder9@verizon.net>
To: Terry Singeltary <flounder9@verizon.net>
Sent: Mon, Jul 27, 2020 3:04 pm
Subject: APHIS USDA Nor98-like scrapie was confirmed in a sheep sampled at slaughter in May 2020

National Scrapie Eradication Program June 2020 Monthly Report Fiscal Year 2020

National Scrapie Eradication Program June 2020 Monthly Report Fiscal Year 2020

National Scrapie Eradication Program June 2020 Monthly Report Fiscal Year 2020

U.S. Department of Agriculture Animal and Plant Health Inspection Service Veterinary Services Strategy and Policy, Ruminant Health Center Small Ruminant Health July 15, 2020

Program Summary

Performance Measures – The percent of cull black-faced sheep found positive at slaughter (Chart 1) and the percent of cull sheep found positive at slaughter and adjusted for face color1 (Chart 2) remains at 0 percent. The retrospective 6-month rolling average of the percent positive, black-faced sheep sampled at RSSS collection sites has been 0 since June 2016.

Scrapie Testing Results2 – Nor98-like scrapie was confirmed in a sheep sampled at slaughter in May 2020. 

In October 2019, lymph node tissue collected from a lamb at slaughter had suspect staining on IHC. Genotype of the lamb was AA at codon 136 and RR at codon 171, which is considered to be resistant to classical scrapie. Additional testing, using three alternative antibodies to scrapie, produced mixed results. Due to the unusual staining, results for this animal were reported as ‘inconclusive’ for classical scrapie. Further testing was conducted on the flock which was depopulated for diagnostic purposes and all samples were not detected by IHC. This case has similar staining to an RR lamb tested in April 2018.

1White, black and mottled-faced color sheep are weighted based on population; white-faced sheep have the greatest weight. If a white-faced positive sheep is found, this statistic will markedly increase. See notes below.

2Samples collected between October 1, 2019 and June 30, 2020, and confirmed by July 15, 2020.

As of June 30, 2020, 23,954 samples have been collected in FY 2020, 19,018 from sheep and 4,936 from goats. 

There have been 488 NVSL confirmed positive animals (473 classical cases – 470 sheep and 3 goats) and 

15 Nor98-like cases since the beginning of RSSS. No animals have tested positive for scrapie in FY 2020.

snip...see full text;


NOR-98
still no map???

WEDNESDAY, MAY 29, 2019 

Incomplete inactivation of atypical scrapie following recommended autoclave decontamination procedures USDA HERE'S YOUR SIGN!


-----Original Message-----
From: Terry Singeltary <flounder9@verizon.net>
To: 
Sent: Tue, Jun 30, 2020 11:12 am
Subject: National Scrapie Eradication Program May 2020 Monthly Report Fiscal Year 2020 U.S. Department of Agriculture Animal and Plant Health Inspection Service Veterinary Services Strategy and Policy, Ruminant Health Center Small Ruminant Health June 15, 2020

National Scrapie Eradication Program May 2020 Monthly Report Fiscal Year 2020 U.S. Department of Agriculture Animal and Plant Health Inspection Service Veterinary Services Strategy and Policy, Ruminant Health Center Small Ruminant Health June 15, 2020

Program Summary

Performance Measures – The percent of cull black-faced sheep found positive at slaughter (Chart 1) and the percent of cull sheep found positive at slaughter and adjusted for face color1 (Chart 2) remains at 0 percent. The retrospective 6-month rolling average of the percent positive, black-faced sheep sampled at RSSS collection sites has been 0 since June 2016.

Scrapie Testing Results2 – In October 2019, lymph node tissue collected from a lamb at slaughter had suspect staining on IHC. Genotype of the lamb was AA at codon 136 and RR at codon 171, which is considered to be resistant to classical scrapie. Additional testing, using three alternative antibodies to scrapie, produced mixed results. Due to the unusual staining, results for this animal were reported as ‘inconclusive’ for classical scrapie. Further testing was conducted on the flock which was depopulated for diagnostic purposes and all samples were not detected by IHC. This case has similar staining to an RR lamb tested in April 2018.

1White, black and mottled-faced color sheep are weighted based on population; white-faced sheep have the greatest weight. If a white-faced positive sheep is found, this statistic will markedly increase. See notes below. 

2Samples collected between October 1, 2019 and May 31, 2020, and confirmed by June 15, 2020.

Program Summary Infected and Source Flocks - There have been no infected herds identified in FY 2020. One flock in Texas has an open infected status since April 2016, but there are no exposed animals on the premises. Cleaning and disinfection of the premises has to be completed before the status can be closed. The number of newly designated infected and source flocks by year since 1997 is shown in Chart 3. The peak was in 2005 with 180 flocks.

Scrapie in Goats –The total number of NVSL confirmed positive cases in goats is 44 since FY 2002. Samples from three of these positive animals were collected through RSSS, one in November 2014, the second in July 2018, and the most recent in June 2019. The remainder of the positive cases have been found through testing of clinical suspects, testing of exposed animals, and trace-out investigations. Figure 1 shows the number of positive cases by State and by fiscal year of last reported case.

Program Summary Scrapie Free Flock Certification Program (SFCP) – As of May 31, 2020, there were 242 flocks participating in the Scrapie Free Flock Certification Program (SFCP). Statuses of these flocks were 40 export monitored, 41 export certified, and 161 select monitored flocks (Figure 2). SFCP open statuses by fiscal year of Status date3 from FY 2007 to FY 2020 are depicted in Chart 4.

3Chart 4 represents the cumulative change in SFCP enrollment over time, and includes open and closed statuses/programs, and active and inactive flocks/herds. Previous charts of SFCP participation by year were manually updated and used the enrollment date to determine the year of participation in SFCP. With the change to Tableau charts, the start/status date is used. Many participating flocks were grandfathered into the Export category in 2013 with an earlier status date.

Surveillance

Surveillance activities are reported by Field Operations Districts shown in Figure 3. Surveillance minimums are based on estimated breeding sheep and goat populations in each State. The distribution of sheep and goat populations by District is depicted in Chart 5.

Components of Scrapie Surveillance

• Regulatory Scrapie Slaughter Surveillance (RSSS) started April 1, 2003. It is a targeted slaughter surveillance program which is designed to identify infected flocks. 

Samples have been collected from 656,214 animals since April 1, 2003. 

As of May 31, 2020, 21,432 samples have been collected in FY 2020, 17,079 from sheep and 4,353 from goats. 

There have been 487 NVSL confirmed positive animals (473 classical cases – 470 sheep and 3 goats) 

and 

14 Nor98-like cases since the beginning of RSSS. No animals have tested positive for scrapie in FY 2020.

 Does not include Nor98-like scrapie cases found through RSSS.

 Does not include Nor98-like scrapie cases found through RSSS.

a map of atypical NOR98-like scrapie could be put up as easily as this map of typical scrapie in Goats imo, on page 13 under Scrapie Cases in Goats FY 2002 – FY 2020

snip...i can't stomach anymore, see full text;


This report is fancy and all with graphs, charts, really shiny and pretty, but, imo, it's nothing more than attempt to water down what has been going on for decades, i.e. let's make this look better than it is, as little surveillance and testing as possible, and let's not talk about the fact that atypical scrapie is just as dangerous to humans and animals, yet the USDA OIE et al went to junk science on that one, and classified it as a legally trading commodity, really dumb in my opinion, and the surveillance efforts are still nothing more than do everything possible NOT to find anymore cases of scrapie tse prion, just like BSE and CWD. i was told years ago there would be a map added of the scrapie and ATYPICAL SCRAPIE cases. oh well, i am not impressed by this report...for whatever that's worth...terry

Front Bioeng Biotechnol. 2020; 8: 164. Published online 2020 Mar 12. doi: 10.3389/fbioe.2020.00164 PMCID: PMC7081731 

The Scrapie Prevalence in a Goat Herd Is Underestimated by Using a Rapid Diagnostic Test 

Timm Konold,1,* John Spiropoulos,1 Jemma Thorne,1 Laura Phelan,1 Louise Fothergill,2 Brenda Rajanayagam,3 Tobias Floyd,1 Beatriz Vidana,1 Judith Charnley,4 Nadya Coates,5 and Marion Simmons1 

Author information Article notes Copyright and License information Disclaimer Associated Data Supplementary Materials Data Availability Statement Go to: 

Abstract 

Current European surveillance regulations for scrapie, a naturally occurring transmissible spongiform encephalopathy (TSE) or prion disease in sheep and goats, require testing of fallen stock or healthy slaughter animals, and outline measures in the case of confirmation of disease. An outbreak of classical scrapie in a herd with 2500 goats led to the culling of the whole herd, providing the opportunity to examine a subset of goats, take samples, and examine them for the presence of disease-associated prion protein (PrPSc) to provide further information on scrapie test sensitivity, pathology, and association with prion protein genotype. Goats were examined clinically prior to cull, and the brains examined post mortem by Bio-Rad ELISA, a rapid screening test used for active surveillance in sheep and goats, and two confirmatory tests, Western blot and immunohistochemistry. Furthermore, up to 10 lymphoid tissues were examined by immunohistochemistry. Of 151 goats examined, three (2.0%) tested positive for scrapie by ELISA on brain, confirmed by confirmatory tests, and a further five (3.3%) were negative by ELISA but positive by at least one of the confirmatory tests. Only two of these, both positive by ELISA, displayed evident signs of scrapie. In addition, 10 (6.6%) goats, which also included two clinical suspects, were negative on brain examination but had detectable PrPSc in lymphoid tissue. PrPSc was detected most frequently in the medial retropharyngeal lymph node (LN; 94.4% of all 18 cases) and palatine tonsil (88.9%). Abnormal behavior and circling or loss of balance when blindfolded were the best clinical discriminators for scrapie status. None of the goats that carried a single allele in the prion protein gene associated with increased resistance to scrapie (Q211, K222, S146) were scrapie-positive, and the percentage of goats with these alleles was greater than expected from previous surveys. Significantly more goats that were scrapie-positive were isoleucine homozygous at codon 142 (II142). The results indicate that the sensitivity of the applied screening test is poor in goats compared to the confirmatory tests as gold standard, particularly for asymptomatic animals. Sensitivity of surveillance could be improved by testing retropharyngeal LN or palatine tonsil in addition to brain.

snip...

Conclusion

The results of this study continue to highlight the limitations of the Bio-Rad ELISA as brain screening test to diagnose classical scrapie in goats, and other or additional tests should be considered. It is recommended to include testing of the medial retropharyngeal LN or palatine tonsil, which are also located at the head that is generally submitted for testing and are less prone to rapid autolysis, to increase the sensitivity of goat scrapie surveillance.

Keywords: transmissible spongiform encephalopathy, prion, classical scrapie, goat, clinical diagnosis, immunohistochemistry, ELISA


TUESDAY, MARCH 31, 2020 

The Scrapie Prevalence in a Goat Herd Is Underestimated by Using a Rapid Diagnostic Test


April 22, 2016 

Scrapie Confirmed in a Hartley County Sheep 

AUSTIN – Texas Animal Health Commission (TAHC) officials have confirmed scrapie in a Hartley County ewe. The ewe was tested by TAHC after the owner reported signs of weight loss and lack of coordination to their local veterinarian. The premises was quarantined and a flock plan for monitoring is being developed by the TAHC and USDA. 

“The TAHC is working closely with the flock owner, sharing all of the options for disease eradication,” said Dr. David Finch, TAHC Region 1 Director. “We are thankful the producer was proactive in identifying a problem and seeking veterinary help immediately.” 

Texas leads the nation in sheep and goat production. Since 2008, there have been no confirmed cases of scrapie in Texas. The last big spike in Texas scrapie cases was in 2006 when nine infected herds were identified and the last herd was released from restrictions in 2013. 

According to USDA regulations, Texas must conduct adequate scrapie surveillance by collecting a minimum of 598 sheep samples annually. Since USDA slaughter surveillance started in FY 2003, the percent of cull sheep found positive for scrapie at slaughter (once adjusted for face color) has decreased 90 percent. 

Scrapie is the oldest known transmissible spongiform encephalopathies, and under natural conditions only sheep and goats are known to be affected by scrapie. It is a fatal disease that affects the central nervous system of sheep and goats. It is not completely understood how scrapie is passed from one animal to the next and apparently healthy sheep infected with scrapie can spread the disease. Sheep and goats are typically infected as young lambs or kids, though adult sheep and goats can become infected. 

The most effective method of scrapie prevention is to maintain a closed flock. Raising replacement ewes, purchasing genetically resistant rams and ewes, or buying from a certified-free scrapie flock are other options to reduce the risk of scrapie. At this time the resistant genetic markers in goats have not been identified, therefore it is important to maintain your sheep and goat herds separately. 

The incubation period for Scrapie is typically two to five years. Producers should record individual identification numbers and the seller’s premise identification number on purchase and sales records. These records must be maintained for a minimum of five years. 

Producers should notify the Texas Animal Health Commission (800-550-8242) or the USDA-Austin Office (512-383-2400) if they have an adult sheep or goat with neurologic signs such as incoordination, behavioral changes, or intense itching with wool loss. Producers may order scrapie identification tags by calling 866-873-2824. 

For more information, please visit our website at: http://www.tahc.texas.gov/animal_health/scrapie/scrapie.html. 

###



***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years


***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded. 


Gudmundur Georgsson,1 Sigurdur Sigurdarson2 and Paul Brown3

Correspondence

Gudmundur Georgsson ggeorgs@hi.is

1 Institute for Experimental Pathology, University of Iceland, Keldur v/vesturlandsveg, IS-112 Reykjavı´k, Iceland

2 Laboratory of the Chief Veterinary Officer, Keldur, Iceland

3 Bethesda, Maryland, USA

Received 7 March 2006 Accepted 6 August 2006

In 1978, a rigorous programme was implemented to stop the spread of, and subsequently eradicate, sheep scrapie in Iceland. Affected flocks were culled, premises were disinfected and, after 2–3 years, restocked with lambs from scrapie-free areas. Between 1978 and 2004, scrapie recurred on 33 farms. Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded. Of special interest was one farm with a small, completely self-contained flock where scrapie recurred 18 years after culling, 2 years after some lambs had been housed in an old sheephouse that had never been disinfected. Epidemiological investigation established with near certitude that the disease had not been introduced from the outside and it is concluded that the agent may have persisted in the old sheep-house for at least 16 years.


WHY NOT SHOW A DETAILED MAP OF ATYPICAL NOR98-like Scrapie $$$

WHAT could some ramifications be from purposely omitting ATYPICAL NOR98-LIKE SCRAPIE???

Tuesday, June 3, 2008

SCRAPIE USA UPDATE JUNE 2008 NOR-98 REPORTED PA

http://nor-98.blogspot.com/2008/06/scrapie-usa-update-june-2008-nor-98.html



Case 6

The sixth case of Nor98 scrapie was identified in a 4-year-old, white-faced ewe that was purchased and added to a commercial flock in Pennsylvania that consisted of approximately 700 head of sheep and goats. Individual animal records were not kept on the premises, so it was impossible to determine exactly how long the ewe was on the farm or her flock of origin. It was estimated that she remained in this flock for approximately 1 month, was sent to slaughter, and was tested for PrPSc as part of the RSSS program. No clinical signs suggestive of scrapie disease were noted. The Prnp genotype of the case 6 ewe was AFRQ/ALRQ (136 AA, 141 FL, 154 RR, 171 QQ). Evaluation of the brain by using HE revealed no lesions. IHC highlighted PrPSc bilaterally in the spinal nucleus of the trigeminal nerve (Fig. 1H) and in the dorsal aspect of the dorsal horns of the cervical spinal cord. PrPSc immunolabeling in the dorsal motor nucleus of the vagus nerve and in lymphoid tissue was absent. Cerebellum was unavailable for evaluation. ELISA and Western blot tests were not done because fresh tissue was unavailable. The commercial flock was depopulated, and adult animals exposed to this ewe were tested for scrapie. No additional cases of Nor98 or classic scrapie were identified. A summary of relevant findings from all cases is shown in Table 1.


THURSDAY, DECEMBER 19, 2019 

The emergence of classical BSE from atypical/Nor98 scrapie


Monday, November 30, 2009
 
USDA AND OIE COLLABORATE TO EXCLUDE ATYPICAL SCRAPIE NOR-98 ANIMAL HEALTH CODE
 
 
Thursday, December 20, 2012
 
*** OIE GROUP RECOMMENDS THAT SCRAPE PRION DISEASE BE DELISTED, WISHES TO CONTINUE SPREADING IT AROUND THE GLOBE
 

This surveillance plan is designed to speed the eradication of classical scrapie. Cases of nonclassical (Nor98-like) scrapie will be found because of testing for classical scrapie but the plan is not designed to maximize these detections. Nor98-like scrapie has its own unique characteristics, and the Animal and Plant Health Inspection Service (APHIS) and the OIE have concluded that it is “clinically, pathologically, biochemically, and epidemiologically unrelated to classical scrapie, may not be contagious and may, in fact, be a spontaneous degenerative condition of older sheep.” As a result, APHIS does not restrict or depopulate animals exposed to Nor98-like scrapie.


***> As a result, APHIS does not restrict or depopulate animals exposed to Nor98-like scrapie.

incredible stupidity, not based on sound science, see;

WEDNESDAY, MAY 29, 2019 

Incomplete inactivation of atypical scrapie following recommended autoclave decontamination procedures USDA HERE'S YOUR SIGN!


***> Thus, atypical scrapie is recognized as a separate, nonreportable disease by the World Organization for Animal Health (OIE).

''as usual, OIE USDA et al put cart before horse, and put human and animal life at risk...terry''

Atypical scrapie has been transmitted experimentally to AHQ sheep by the intracranial145 and oral146 routes. An increased risk of atypical scrapie has also been identified in sheep with the AF141RQ haplotype.137 Atypical scrapie does experimentally transmit to sheep with the AL141RQ haplotype but with very long incubation periods without clinical signs.123 Furthermore, sheep with the ARR haplotype, which confers resistance to classical scrapie and is the cornerstone of genotype-based eradication programs, do not appear to be protected against developing atypical scrapie.41,137

Atypical scrapie has also been reported in goats,103,142 where the molecular profile on western blot is similar to atypical scrapie in sheep, but the distribution of lesions within the brain is more rostral (thalamus and midbrain) than atypical scrapie of sheep.142 Similar to sheep with atypical scrapie, histidine substitution at PRNP codon 154 is a risk factor for atypical scrapie in goats,32 and PrPSc has not been demonstrated in the lymphoid tissues of affected goats.142

end...see;

A newly identified type of scrapie agent can naturally infect sheep with resistant PrP genotypes

Annick Le Dur*,?, Vincent Béringue*,?, Olivier Andréoletti?, Fabienne Reine*, Thanh Lan Laï*, Thierry Baron§, Bjørn Bratberg¶, Jean-Luc Vilotte?, Pierre Sarradin**, Sylvie L. Benestad¶, and Hubert Laude*,?? +Author Affiliations

*Virologie Immunologie Moléculaires and ?Génétique Biochimique et Cytogénétique, Institut National de la Recherche Agronomique, 78350 Jouy-en-Josas, France; ?Unité Mixte de Recherche, Institut National de la Recherche Agronomique-Ecole Nationale Vétérinaire de Toulouse, Interactions Hôte Agent Pathogène, 31066 Toulouse, France; §Agence Française de Sécurité Sanitaire des Aliments, Unité Agents Transmissibles Non Conventionnels, 69364 Lyon, France; **Pathologie Infectieuse et Immunologie, Institut National de la Recherche Agronomique, 37380 Nouzilly, France; and ¶Department of Pathology, National Veterinary Institute, 0033 Oslo, Norway

***Edited by Stanley B. Prusiner, University of California, San Francisco, CA (received for review March 21, 2005)

Abstract 

Scrapie in small ruminants belongs to transmissible spongiform encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative disorders that affect humans and animals and can transmit within and between species by ingestion or inoculation. Conversion of the host-encoded prion protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP (PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified surveillance of scrapie in the European Union, together with the improvement of PrPSc detection techniques, has led to the discovery of a growing number of so-called atypical scrapie cases. These include clinical Nor98 cases first identified in Norwegian sheep on the basis of unusual pathological and PrPSc molecular features and "cases" that produced discordant responses in the rapid tests currently applied to the large-scale random screening of slaughtered or fallen animals. Worryingly, a substantial proportion of such cases involved sheep with PrP genotypes known until now to confer natural resistance to conventional scrapie. Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice.

*** These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.


OR

***The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.


OR

*** Intriguingly, these conclusions suggest that some pathological features of Nor98 are reminiscent of Gerstmann-Sträussler-Scheinker disease.


OR here;



*** The discovery of previously unrecognized prion diseases in both humans and animals (i.e., Nor98 in small ruminants) demonstrates that the range of prion diseases might be wider than expected and raises crucial questions about the epidemiology and strain properties of these new forms. We are investigating this latter issue by molecular and biological comparison of VPSPr, GSS and Nor98.

VARIABLY PROTEASE-SENSITVE PRIONOPATHY IS TRANSMISSIBLE ...price of prion poker goes up again $

OR-10: Variably protease-sensitive prionopathy is transmissible in bank voles

Romolo Nonno,1 Michele Di Bari,1 Laura Pirisinu,1 Claudia D’Agostino,1 Stefano Marcon,1 Geraldina Riccardi,1 Gabriele Vaccari,1 Piero Parchi,2 Wenquan Zou,3 Pierluigi Gambetti,3 Umberto Agrimi1 1Istituto Superiore di Sanità; Rome, Italy; 2Dipartimento di Scienze Neurologiche, Università di Bologna; Bologna, Italy; 3Case Western Reserve University; Cleveland, OH USA

Background. Variably protease-sensitive prionopathy (VPSPr) is a recently described “sporadic”neurodegenerative disease involving prion protein aggregation, which has clinical similarities with non-Alzheimer dementias, such as fronto-temporal dementia. Currently, 30 cases of VPSPr have been reported in Europe and USA, of which 19 cases were homozygous for valine at codon 129 of the prion protein (VV), 8 were MV and 3 were MM. A distinctive feature of VPSPr is the electrophoretic pattern of PrPSc after digestion with proteinase K (PK). After PK-treatment, PrP from VPSPr forms a ladder-like electrophoretic pattern similar to that described in GSS cases. The clinical and pathological features of VPSPr raised the question of the correct classification of VPSPr among prion diseases or other forms of neurodegenerative disorders. Here we report preliminary data on the transmissibility and pathological features of VPSPr cases in bank voles.

Materials and Methods. Seven VPSPr cases were inoculated in two genetic lines of bank voles, carrying either methionine or isoleucine at codon 109 of the prion protein (named BvM109 and BvI109, respectively). Among the VPSPr cases selected, 2 were VV at PrP codon 129, 3 were MV and 2 were MM. Clinical diagnosis in voles was confirmed by brain pathological assessment and western blot for PK-resistant PrPSc (PrPres) with mAbs SAF32, SAF84, 12B2 and 9A2.

Results. To date, 2 VPSPr cases (1 MV and 1 MM) gave positive transmission in BvM109. Overall, 3 voles were positive with survival time between 290 and 588 d post inoculation (d.p.i.). All positive voles accumulated PrPres in the form of the typical PrP27–30, which was indistinguishable to that previously observed in BvM109 inoculated with sCJDMM1 cases.

In BvI109, 3 VPSPr cases (2 VV and 1 MM) showed positive transmission until now. Overall, 5 voles were positive with survival time between 281 and 596 d.p.i.. In contrast to what observed in BvM109, all BvI109 showed a GSS-like PrPSc electrophoretic pattern, characterized by low molecular weight PrPres. These PrPres fragments were positive with mAb 9A2 and 12B2, while being negative with SAF32 and SAF84, suggesting that they are cleaved at both the C-terminus and the N-terminus. Second passages are in progress from these first successful transmissions.

Conclusions. Preliminary results from transmission studies in bank voles strongly support the notion that VPSPr is a transmissible prion disease. Interestingly, VPSPr undergoes divergent evolution in the two genetic lines of voles, with sCJD-like features in BvM109 and GSS-like properties in BvI109.

The discovery of previously unrecognized prion diseases in both humans and animals (i.e., Nor98 in small ruminants) demonstrates that the range of prion diseases might be wider than expected and raises crucial questions about the epidemiology and strain properties of these new forms. We are investigating this latter issue by molecular and biological comparison of VPSPr, GSS and Nor98.


P.97: Scrapie transmits to white-tailed deer by the oral route and has a molecular profile similar to chronic wasting disease and distinct from the scrapie inoculum

Justin Greenlee1, S JO Moore1, Jodi Smith1, M Heather WestGreenlee2 and Robert Kunkle1

1National Animal Disease Center; Ames, IA USA

2Iowa State University; Ames, IA USA

The purpose of this work was to determine susceptibility of white-tailed deer (WTD) to the agent of sheep scrapie and to compare the resultant PrPSc to that of the original inoculum and chronic wasting disease (CWD). We inoculated WTD by a natural route of exposure (concurrent oral and intranasal (IN); n = 5) with a US scrapie isolate. All scrapie-inoculated deer had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues at preclinical time points, and deer necropsied after 28 months post-inoculation had clinical signs, spongiform encephalopathy, and widespread distribution of PrPSc in neural and lymphoid tissues. Western blotting (WB) revealed PrPSc with 2 distinct molecular profiles. WB on cerebral cortex had a profile similar to the original scrapie inoculum, whereas WB of brainstem, cerebellum, or lymph nodes revealed PrPSc with a higher profile resembling CWD. Homogenates with the 2 distinct profiles from WTD with clinical scrapie were further passaged to mice expressing cervid prion protein and intranasally to sheep and WTD. In cervidized mice, the 2 inocula have distinct incubation times. Sheep inoculated intranasally with WTD derived scrapie developed disease, but only after inoculation with the inoculum that had a scrapie-like profile. The WTD study is ongoing, but deer in both inoculation groups are positive for PrPSc by rectal mucosal biopsy. 

***In summary, this work demonstrates that WTD are susceptible to the agent of scrapie, 2 distinct molecular profiles of PrPSc are present in the tissues of affected deer, and inoculum of either profile readily passes to deer.


*** After a natural route of exposure, 100% of WTD were susceptible to scrapie.

PO-039: A comparison of scrapie and chronic wasting disease in white-tailed deer Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture; Agricultural Research Service, National Animal Disease Center; Ames, IA USA

 
White-tailed deer are susceptible to the agent of sheep scrapie by intracerebral inoculation

snip...

It is unlikely that CWD will be eradicated from free-ranging cervids, and the disease is likely to continue to spread geographically [10]. However, the potential that white-tailed deer may be susceptible to sheep scrapie by a natural route presents an additional confounding factor to halting the spread of CWD. This leads to the additional speculations that

1) infected deer could serve as a reservoir to infect sheep with scrapie offering challenges to scrapie eradication efforts and

2) CWD spread need not remain geographically confined to current endemic areas, but could occur anywhere that sheep with scrapie and susceptible cervids cohabitate.

This work demonstrates for the first time that white-tailed deer are susceptible to sheep scrapie by intracerebral inoculation with a high attack rate and that the disease that results has similarities to CWD. These experiments will be repeated with a more natural route of inoculation to determine the likelihood of the potential transmission of sheep scrapie to white-tailed deer. If scrapie were to occur in white-tailed deer, results of this study indicate that it would be detected as a TSE, but may be difficult to differentiate from CWD without in-depth biochemical analysis.



2012

PO-039: A comparison of scrapie and chronic wasting disease in white-tailed deer

Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture; Agricultural Research Service, National Animal Disease Center; Ames, IA USA

snip...

The results of this study suggest that there are many similarities in the manifestation of CWD and scrapie in WTD after IC inoculation including early and widespread presence of PrPSc in lymphoid tissues, clinical signs of depression and weight loss progressing to wasting, and an incubation time of 21-23 months. Moreover, western blots (WB) done on brain material from the obex region have a molecular profile similar to CWD and distinct from tissues of the cerebrum or the scrapie inoculum. However, results of microscopic and IHC examination indicate that there are differences between the lesions expected in CWD and those that occur in deer with scrapie: amyloid plaques were not noted in any sections of brain examined from these deer and the pattern of immunoreactivity by IHC was diffuse rather than plaque-like.

*** After a natural route of exposure, 100% of WTD were susceptible to scrapie.

Deer developed clinical signs of wasting and mental depression and were necropsied from 28 to 33 months PI. Tissues from these deer were positive for PrPSc by IHC and WB. Similar to IC inoculated deer, samples from these deer exhibited two different molecular profiles: samples from obex resembled CWD whereas those from cerebrum were similar to the original scrapie inoculum. On further examination by WB using a panel of antibodies, the tissues from deer with scrapie exhibit properties differing from tissues either from sheep with scrapie or WTD with CWD. Samples from WTD with CWD or sheep with scrapie are strongly immunoreactive when probed with mAb P4, however, samples from WTD with scrapie are only weakly immunoreactive. In contrast, when probed with mAb’s 6H4 or SAF 84, samples from sheep with scrapie and WTD with CWD are weakly immunoreactive and samples from WTD with scrapie are strongly positive. This work demonstrates that WTD are highly susceptible to sheep scrapie, but on first passage, scrapie in WTD is differentiable from CWD.

 
2011

*** After a natural route of exposure, 100% of white-tailed deer were susceptible to scrapie.


ZOONOSIS OF SCRAPIE TSE PRION

O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations 

Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). 

Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods. 

*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period, 

***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014), 

***is the third potentially zoonotic PD (with BSE and L-type BSE), 

***thus questioning the origin of human sporadic cases. 

We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health. 

=============== 

***thus questioning the origin of human sporadic cases*** 

=============== 

***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals. 

============== 


***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. 

 
PRION 2016 TOKYO

Saturday, April 23, 2016

SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016

Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online

Taylor & Francis

Prion 2016 Animal Prion Disease Workshop Abstracts

WS-01: Prion diseases in animals and zoonotic potential

Juan Maria Torres a, Olivier Andreoletti b, J uan-Carlos Espinosa a. Vincent Beringue c. Patricia Aguilar a,

Natalia Fernandez-Borges a. and Alba Marin-Moreno a

"Centro de Investigacion en Sanidad Animal ( CISA-INIA ). Valdeolmos, Madrid. Spain; b UMR INRA -ENVT 1225 Interactions Holes Agents Pathogenes. ENVT. Toulouse. France: "UR892. Virologie lmmunologie MolécuIaires, Jouy-en-Josas. France

Dietary exposure to bovine spongiform encephalopathy (BSE) contaminated bovine tissues is considered as the origin of variant Creutzfeldt Jakob (vCJD) disease in human. To date, BSE agent is the only recognized zoonotic prion... Despite the variety of Transmissible Spongiform Encephalopathy (TSE) agents that have been circulating for centuries in farmed ruminants there is no apparent epidemiological link between exposure to ruminant products and the occurrence of other form of TSE in human like sporadic Creutzfeldt Jakob Disease (sCJD). However, the zoonotic potential of the diversity of circulating TSE agents has never been systematically assessed. The major issue in experimental assessment of TSEs zoonotic potential lies in the modeling of the ‘species barrier‘, the biological phenomenon that limits TSE agents’ propagation from a species to another. In the last decade, mice genetically engineered to express normal forms of the human prion protein has proved essential in studying human prions pathogenesis and modeling the capacity of TSEs to cross the human species barrier.

To assess the zoonotic potential of prions circulating in farmed ruminants, we study their transmission ability in transgenic mice expressing human PrPC (HuPrP-Tg). Two lines of mice expressing different forms of the human PrPC (129Met or 129Val) are used to determine the role of the Met129Val dimorphism in susceptibility/resistance to the different agents.

These transmission experiments confirm the ability of BSE prions to propagate in 129M- HuPrP-Tg mice and demonstrate that Met129 homozygotes may be susceptible to BSE in sheep or goat to a greater degree than the BSE agent in cattle and that these agents can convey molecular properties and neuropathological indistinguishable from vCJD. However homozygous 129V mice are resistant to all tested BSE derived prions independently of the originating species suggesting a higher transmission barrier for 129V-PrP variant.

Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. 

 
***> why do we not want to do TSE transmission studies on chimpanzees $

5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. 

***> I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. 

***> Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

snip...

R. BRADLEY


Title: Transmission of scrapie prions to primate after an extended silent incubation period) 

*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS. 

*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated. 

*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains. 


***> Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility. <***

Transmission of scrapie prions to primate after an extended silent incubation period 

Emmanuel E. Comoy, Jacqueline Mikol, Sophie Luccantoni-Freire, Evelyne Correia, Nathalie Lescoutra-Etchegaray, Valérie Durand, Capucine Dehen, Olivier Andreoletti, Cristina Casalone, Juergen A. Richt, Justin J. Greenlee, Thierry Baron, Sylvie L. Benestad, Paul Brown & Jean-Philippe Deslys Scientific Reports volume 5, Article number: 11573 (2015) | Download Citation

Abstract 

Classical bovine spongiform encephalopathy (c-BSE) is the only animal prion disease reputed to be zoonotic, causing variant Creutzfeldt-Jakob disease (vCJD) in humans and having guided protective measures for animal and human health against animal prion diseases. Recently, partial transmissions to humanized mice showed that the zoonotic potential of scrapie might be similar to c-BSE. We here report the direct transmission of a natural classical scrapie isolate to cynomolgus macaque, a highly relevant model for human prion diseases, after a 10-year silent incubation period, with features similar to those reported for human cases of sporadic CJD. Scrapie is thus actually transmissible to primates with incubation periods compatible with their life expectancy, although fourfold longer than BSE. Long-term experimental transmission studies are necessary to better assess the zoonotic potential of other prion diseases with high prevalence, notably Chronic Wasting Disease of deer and elk and atypical/Nor98 scrapie.

SNIP...

Discussion We describe the transmission of spongiform encephalopathy in a non-human primate inoculated 10 years earlier with a strain of sheep c-scrapie. Because of this extended incubation period in a facility in which other prion diseases are under study, we are obliged to consider two alternative possibilities that might explain its occurrence. We first considered the possibility of a sporadic origin (like CJD in humans). Such an event is extremely improbable because the inoculated animal was 14 years old when the clinical signs appeared, i.e. about 40% through the expected natural lifetime of this species, compared to a peak age incidence of 60–65 years in human sporadic CJD, or about 80% through their expected lifetimes. Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.

The second possibility is a laboratory cross-contamination. Three facts make this possibility equally unlikely. First, handling of specimens in our laboratory is performed with fastidious attention to the avoidance of any such cross-contamination. Second, no laboratory cross-contamination has ever been documented in other primate laboratories, including the NIH, even between infected and uninfected animals housed in the same or adjacent cages with daily intimate contact (P. Brown, personal communication). Third, the cerebral lesion profile is different from all the other prion diseases we have studied in this model19, with a correlation between cerebellar lesions (massive spongiform change of Purkinje cells, intense PrPres staining and reactive gliosis26) and ataxia. The iron deposits present in the globus pallidus are a non specific finding that have been reported previously in neurodegenerative diseases and aging27. Conversely, the thalamic lesion was reminiscent of a metabolic disease due to thiamine deficiency28 but blood thiamine levels were within normal limits (data not shown). The preferential distribution of spongiform change in cortex associated with a limited distribution in the brainstem is reminiscent of the lesion profile in MM2c and VV1 sCJD patients29, but interspecies comparison of lesion profiles should be interpreted with caution. It is of note that the same classical scrapie isolate induced TSE in C57Bl/6 mice with similar incubation periods and lesional profiles as a sample derived from a MM1 sCJD patient30.

We are therefore confident that the illness in this cynomolgus macaque represents a true transmission of a sheep c-scrapie isolate directly to an old-world monkey, which taxonomically resides in the primate subdivision (parvorder of catarrhini) that includes humans. With an homology of its PrP protein with humans of 96.4%31, cynomolgus macaque constitutes a highly relevant model for assessing zoonotic risk of prion diseases. Since our initial aim was to show the absence of transmission of scrapie to macaques in the worst-case scenario, we obtained materials from a flock of naturally-infected sheep, affecting animals with different genotypes32. This c-scrapie isolate exhibited complete transmission in ARQ/ARQ sheep (332 ± 56 days) and Tg338 transgenic mice expressing ovine VRQ/VRQ prion protein (220 ± 5 days) (O. Andreoletti, personal communication). From the standpoint of zoonotic risk, it is important to note that sheep with c-scrapie (including the isolate used in our study) have demonstrable infectivity throughout their lymphoreticular system early in the incubation period of the disease (3 months-old for all the lymphoid organs, and as early as 2 months-old in gut-associated lymph nodes)33. In addition, scrapie infectivity has been identified in blood34, milk35 and skeletal muscle36 from asymptomatic but scrapie infected small ruminants which implies a potential dietary exposure for consumers.

Two earlier studies have reported the occurrence of clinical TSE in cynomolgus macaques after exposures to scrapie isolates. In the first study, the “Compton” scrapie isolate (derived from an English sheep) and serially propagated for 9 passages in goats did not transmit TSE in cynomolgus macaque, rhesus macaque or chimpanzee within 7 years following intracerebral challenge1; conversely, after 8 supplementary passages in conventional mice, this “Compton” isolate induced TSE in a cynomolgus macaque 5 years after intracerebral challenge, but rhesus macaques and chimpanzee remained asymptomatic 8.5 years post-exposure8. However, multiple successive passages that are classically used to select laboratory-adapted prion strains can significantly modify the initial properties of a scrapie isolate, thus questioning the relevance of zoonotic potential for the initial sheep-derived isolate. The same isolate had also induced disease into squirrel monkeys (new-world monkey)9. A second historical observation reported that a cynomolgus macaque developed TSE 6 years post-inoculation with brain homogenate from a scrapie-infected Suffolk ewe (derived from USA), whereas a rhesus macaque and a chimpanzee exposed to the same inoculum remained healthy 9 years post-exposure1. This inoculum also induced TSE in squirrel monkeys after 4 passages in mice. Other scrapie transmission attempts in macaque failed but had more shorter periods of observation in comparison to the current study. Further, it is possible that there are differences in the zoonotic potential of different scrapie strains.

The most striking observation in our study is the extended incubation period of scrapie in the macaque model, which has several implications. Firstly, our observations constitute experimental evidence in favor of the zoonotic potential of c-scrapie, at least for this isolate that has been extensively studied32,33,34,35,36. The cross-species zoonotic ability of this isolate should be confirmed by performing duplicate intracerebral exposures and assessing the transmissibility by the oral route (a successful transmission of prion strains through the intracerebral route may not necessarily indicate the potential for oral transmission37). However, such confirmatory experiments may require more than one decade, which is hardly compatible with current general management and support of scientific projects; thus this study should be rather considered as a case report.

Secondly, transmission of c-BSE to primates occurred within 8 years post exposure for the lowest doses able to transmit the disease (the survival period after inoculation is inversely proportional to the initial amount of infectious inoculum). The occurrence of scrapie 10 years after exposure to a high dose (25 mg) of scrapie-infected sheep brain suggests that the macaque has a higher species barrier for sheep c-scrapie than c-BSE, although it is notable that previous studies based on in vitro conversion of PrP suggested that BSE and scrapie prions would have a similar conversion potential for human PrP38.

Thirdly, prion diseases typically have longer incubation periods after oral exposure than after intracerebral inoculations: since humans can develop Kuru 47 years after oral exposure39, an incubation time of several decades after oral exposure to scrapie would therefore be expected, leading the disease to occur in older adults, i.e. the peak age for cases considered to be sporadic disease, and making a distinction between scrapie-associated and truly sporadic disease extremely difficult to appreciate.

Fourthly, epidemiologic evidence is necessary to confirm the zoonotic potential of an animal disease suggested by experimental studies. A relatively short incubation period and a peculiar epidemiological situation (e.g., all the first vCJD cases occurring in the country with the most important ongoing c-BSE epizootic) led to a high degree of suspicion that c-BSE was the cause of vCJD. Sporadic CJD are considered spontaneous diseases with an almost stable and constant worldwide prevalence (0.5–2 cases per million inhabitants per year), and previous epidemiological studies were unable to draw a link between sCJD and classical scrapie6,7,40,41, even though external causes were hypothesized to explain the occurrence of some sCJD clusters42,43,44. However, extended incubation periods exceeding several decades would impair the predictive values of epidemiological surveillance for prion diseases, already weakened by a limited prevalence of prion diseases and the multiplicity of isolates gathered under the phenotypes of “scrapie” and “sporadic CJD”.

Fifthly, considering this 10 year-long incubation period, together with both laboratory and epidemiological evidence of decade or longer intervals between infection and clinical onset of disease, no premature conclusions should be drawn from negative transmission studies in cynomolgus macaques with less than a decade of observation, as in the aforementioned historical transmission studies of scrapie to primates1,8,9. Our observations and those of others45,46 to date are unable to provide definitive evidence regarding the zoonotic potential of CWD, atypical/Nor98 scrapie or H-type BSE. The extended incubation period of the scrapie-affected macaque in the current study also underscores the limitations of rodent models expressing human PrP for assessing the zoonotic potential of some prion diseases since their lifespan remains limited to approximately two years21,47,48. This point is illustrated by the fact that the recently reported transmission of scrapie to humanized mice was not associated with clinical signs for up to 750 days and occurred in an extreme minority of mice with only a marginal increase in attack rate upon second passage13. The low attack rate in these studies is certainly linked to the limited lifespan of mice compared to the very long periods of observation necessary to demonstrate the development of scrapie. Alternatively, one could estimate that a successful second passage is the result of strain adaptation to the species barrier, thus poorly relevant of the real zoonotic potential of the original scrapie isolate of sheep origin49. The development of scrapie in this primate after an incubation period compatible with its lifespan complements the study conducted in transgenic (humanized) mice; taken together these studies suggest that some isolates of sheep scrapie can promote misfolding of the human prion protein and that scrapie can develop within the lifespan of some primate species.

In addition to previous studies on scrapie transmission to primate1,8,9 and the recently published study on transgenic humanized mice13, our results constitute new evidence for recommending that the potential risk of scrapie for human health should not be dismissed. Indeed, human PrP transgenic mice and primates are the most relevant models for investigating the human transmission barrier. To what extent such models are informative for measuring the zoonotic potential of an animal TSE under field exposure conditions is unknown. During the past decades, many protective measures have been successfully implemented to protect cattle from the spread of c-BSE, and some of these measures have been extended to sheep and goats to protect from scrapie according to the principle of precaution. Since cases of c-BSE have greatly reduced in number, those protective measures are currently being challenged and relaxed in the absence of other known zoonotic animal prion disease. We recommend that risk managers should be aware of the long term potential risk to human health of at least certain scrapie isolates, notably for lymphotropic strains like the classical scrapie strain used in the current study. Relatively high amounts of infectivity in peripheral lymphoid organs in animals infected with these strains could lead to contamination of food products produced for human consumption. Efforts should also be maintained to further assess the zoonotic potential of other animal prion strains in long-term studies, notably lymphotropic strains with high prevalence like CWD, which is spreading across North America, and atypical/Nor98 scrapie (Nor98)50 that was first detected in the past two decades and now represents approximately half of all reported cases of prion diseases in small ruminants worldwide, including territories previously considered as scrapie free... Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.


Like lambs to the slaughter 

* 31 March 2001 * 

Debora MacKenzie * 

Magazine issue 2284 

Suspect symptoms 

What if you can catch old-fashioned CJD by eating meat from a sheep infected with scrapie? 

Exclusive from New Scientist magazine 

Four years ago, Terry Singeltary watched his mother die horribly from a degenerative brain disease. Doctors told him it was Alzheimer's, but Singeltary was suspicious. 

The diagnosis didn't fit her violent symptoms, and he demanded an autopsy. It showed she had died of sporadic Creutzfeldt-Jakob disease. 

Photo: Murdo McLeod 

Most doctors believe that sCJD is caused by a prion protein deforming by chance into a killer. But Singeltary thinks otherwise. 

He is one of a number of campaigners who say that some sCJD, like the variant CJD related to BSE, is caused by eating meat from infected animals. 

Their suspicions have focused on sheep carrying scrapie, a BSE-like disease that is widespread in flocks across Europe and North America. 

Now scientists in France have stumbled across new evidence that adds weight to the campaigners' fears. 

To their complete surprise, the researchers found that one strain of scrapie causes the same brain damage in mice as sCJD. 

"This means we cannot rule out that at least some sCJD may be caused by some strains of scrapie," says team member Jean-Philippe Deslys of the French Atomic Energy Commission's medical research laboratory in Fontenay-aux-Roses, south-west of Paris. 

Hans Kretschmar of the University of Göttingen, who coordinates CJD surveillance in Germany, is so concerned by the findings that he now wants to trawl back through past sCJD cases to see if any might have been caused by eating infected mutton or lamb. 

Brain damage Scrapie has been around for centuries and until now there has been no evidence that it poses a risk to human health. 

But if the French finding means that scrapie can cause sCJD in people, countries around the world may have overlooked a CJD crisis to rival that caused by BSE. 

Deslys and colleagues were originally studying vCJD, not sCJD. 

They injected the brains of macaque monkeys with brain from BSE cattle, and from French and British vCJD patients. The brain damage and clinical symptoms in the monkeys were the same for all three. 

Mice injected with the original sets of brain tissue or with infected monkey brain also developed the same symptoms. 

As a control experiment, the team also injected mice with brain tissue from people and animals with other prion diseases: a French case of sCJD; a French patient who caught sCJD from human-derived growth hormone; sheep with a French strain of scrapie; and mice carrying a prion derived from an American scrapie strain. 

As expected, they all affected the brain in a different way from BSE and vCJD. 

But while the American strain of scrapie caused different damage from sCJD, the French strain produced exactly the same pathology. Multiple strains "The main evidence that scrapie does not affect humans has been epidemiology," says Moira Bruce of the neuropathogenesis unit of the Institute for Animal Health in Edinburgh, who was a member of the same team as Deslys. 

"You see about the same incidence of the disease everywhere, whether or not there are many sheep, and in countries such as New Zealand with no scrapie," she says. 

In the only previous comparisons of sCJD and scrapie in mice, Bruce found they were dissimilar. But there are more than 20 strains of scrapie, and six of sCJD. 

"You would not necessarily see a relationship between the two with epidemiology if only some strains affect only some people," says Deslys. 

Bruce is cautious about the mouse results, but agrees they require further investigation. 

Other trials of scrapie and sCJD in mice, she says, are in progress. 

Deformed proteins People can have three different genetic variations of the human prion protein, and each type of protein can fold up two different ways. 

Kretschmar has found that these six combinations correspond to six clinical types of sCJD: each type of normal prion produces a particular pathology when it spontaneously deforms to produce sCJD. But if these proteins deform because of infection with a disease-causing prion, the relationship between pathology and prion type should be different, as it is in vCJD. 

"If we look at brain samples from sporadic CJD cases and find some that do not fit the pattern," says Kretschmar, "that could mean they were caused by infection." 

There are 250 deaths per year from sCJD in the US, and a similar incidence elsewhere. 

Singeltary and other US activists think that some of these people died after eating contaminated meat or "nutritional" pills containing dried animal brain. 

Governments will have a hard time facing activists like Singeltary if it turns out that some sCJD isn't as spontaneous as doctors have insisted. 

Deslys's work on macaques also provides further proof that the human disease vCJD is caused by BSE. 

And the experiments showed that vCJD is much more virulent to primates than BSE, even when injected into the bloodstream rather than the brain. This, says Deslys, means that there is an even bigger risk than we thought that vCJD can be passed from one patient to another through contaminated blood transfusions and surgical instruments. 

More at: Proceedings of the National Academy of Sciences (vol 98, p 4142) 


Correspondence about this story should be directed to letters@newscientist.com 1900 GMT, 28 March 2001 

* New Scientist 





Chronic Wasting Disease CWD TSE Prion

Cervid to human prion transmission 

Kong, Qingzhong Case Western Reserve University, Cleveland, OH, United States

We hypothesize that: 

(1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues; 

(2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence; 

(3) Reliable essays can be established to detect CWD infection in humans; and 

(4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches. 


ZOONOTIC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE

here is the latest;

PRION 2018 CONFERENCE 

Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice 

Hermann M. Schatzl, Samia Hannaoui, Yo-Ching Cheng, Sabine Gilch (Calgary Prion Research Unit, University of Calgary, Calgary, Canada) Michael Beekes (RKI Berlin), Walter Schulz-Schaeffer (University of Homburg/Saar, Germany), Christiane Stahl-Hennig (German Primate Center) & Stefanie Czub (CFIA Lethbridge). 

To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. 

After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were detected in spinal cord and brain of some euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and pre-clinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. 

Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. 

The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. 
Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. 

The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.. 

***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <*** 

https://prion2018.org/

READING OVER THE PRION 2018 ABSTRACT BOOK, LOOKS LIKE THEY FOUND THAT from this study ; 

P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States 

Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1) (1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.. 

SEEMS THAT THEY FOUND Highly endemic states had a higher rate of prion disease mortality compared to non-CWD 
states. 

AND ANOTHER STUDY; 

P172 Peripheral Neuropathy in Patients with Prion Disease 

Wang H(1), Cohen M(1), Appleby BS(1,2) (1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio.. 

IN THIS STUDY, THERE WERE autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017, 

AND 

included 104 patients. SEEMS THEY FOUND THAT The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%), 

AND 

THAT The Majority of cases were male (60%), AND half of them had exposure to wild game. 

snip...

see more on Prion 2017 Macaque study from Prion 2017 Conference and other updated science on cwd tse prion zoonosis below...terry 

https://prion2018.org/wp-content/uploads/2018/05/program.pdf 

https://prion2018.org/

THURSDAY, OCTOBER 04, 2018 

Cervid to human prion transmission 5R01NS088604-04 Update 

http://grantome.com/grant/NIH/R01-NS088604-04 

http://chronic-wasting-disease.blogspot.com/2018/10/cervid-to-human-prion-transmission.html

snip...full text;

SATURDAY, FEBRUARY 09, 2019 

Experts: Yes, chronic wasting disease in deer is a public health issue — for people


FRIDAY, JULY 26, 2019 

Chronic Wasting Disease in Cervids: Implications for Prion Transmission to Humans and Other Animal Species


1: J Infect Dis 1980 Aug;142(2):205-8

Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates.

Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.

Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.

snip...

The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease.

PMID: 6997404


Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias"

Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the acrapie problem urgent if the sheep industry is not to suffer grievously.

snip...

76/10.12/4.6


Nature. 1972 Mar 10;236(5341):73-4.

Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).

Gibbs CJ Jr, Gajdusek DC.

Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0

Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)

C. J. GIBBS jun. & D. C. GAJDUSEK

National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland

SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).



IN CONFIDENCE SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE

reference...

RB3.20

TRANSMISSION TO CHIMPANZEES

1. Kuru and CJD have been successfully transmitted to chimpanzees but scrapie and TME have not.

2. We cannot say that scrapie will not transmit to chimpanzees. There are several scrapie strains and I am not aware that all have been tried (that would have to be from mouse passaged material). Nor has a wide enough range of field isolates subsequently strain typed in mice been inoculated by the appropriate routes (i/c, ilp and i/v) :

3. I believe the proposed experiment to determine transmissibility, if conducted, would only show the susceptibility or resistance of the chimpanzee to infection/disease by the routes used and the result could not be interpreted for the predictability of the susceptibility for man. Proposals for prolonged oral exposure of chimpanzees to milk from cattle were suggested a long while ago and rejected.

4. In view of Dr Gibbs' probable use of chimpazees Mr Wells' comments (enclosed) are pertinent. I have yet to receive a direct communication from Dr Schellekers but before any collaboration or provision of material we should identify the Gibbs' proposals and objectives.

5. A positive result from a chimpanzee challenged severely would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

6. A negative result would take a lifetime to determine but that would be a shorter period than might be available for human exposure and it would still not answer the question regarding mans' susceptibility. In the meantime no doubt the negativity would be used defensively. It would however be counterproductive if the experiment finally became positive. We may learn more about public reactions following next Monday' s meeting.

R. Bradley

23 September 1990

CVO (+Mr Wells' comments)

Dr T W A Little

Dr B J Shreeve

90/9.23/1.1.



IN CONFIDENCE CHIMPANZEES

CODE 18-77 Reference RB3.46

Some further information that may assist in decision making has been gained by discussion with Dr Rosalind Ridley.

She says that careful study of Gajdusek's work shows no increased susceptibility of chimpanzees over New World Monkeys such as Squirrel Monkeys. She does not think it would tell you anything about the susceptibility to man. Also Gajdusek did not, she believes, challenge chimpanzees with scrapie as severely as we did pigs and we know little of that source of scrapie. Comparisons would be difficult. She also would not expect the Home Office to sanction such experiments here unless there was a very clear and important objective that would be important for human health protection. She doubted such a case could be made. If this is the case she thought it would be unethical to do an experiment abroad because we could not do it in our own country.

Retrospectively she feels they should have put up more marmosets than they did. They all remain healthy. They would normally regard the transmission as negative if no disease resulted in five years.

We are not being asked for a decision but I think that before we made one we should gain as much knowledge as we can. If we decided to proceed we would have to bear any criticisms for many years if there was an adverse view by scientists or­media. This should not be undertaken lightly. There is already some adverse comment here, I gather, on the pig experiment though that will subside.

The Gibbs' (as' distinct from Schellekers') study is somewhat different. We are merely supplying material for comparative studies in a laboratory with the greatest experience of human SEs in the world and it has been sanctioned by USDA (though we do not know for certain yet if chimpanzees specifically will be used). This would keep it at a lower profile than if we conducted such an experiment in the UK or Europe.

I consider we must have very powerful and defendable objectives to go beyond Gibbs' proposed experiments and should not initiate others just because an offer has been made.

Scientists have a responsibility to seek other methods of investigative research other than animal experimentation. At present no objective has convinced me we need to do research using Chimpanzees - a species in need of protection. Resisting such proposals would enable us to communicate that information to the scientist and the public should the need arise. A line would have been drawn.

CVO cc Dr T Dr B W A Little Dr B J Shreeve

R Bradley

26 September 1990

90/9.26/3.2



Possible Changes in the Scrapie Agent


I AM NOT AN ADVOCATE FOR EXPERIMENTAL USE OF CHIMPANZEES AS TEST VICTIMS. However, I would be an advocate for (and i have said this before over the years), of death row inmates being used. Their families could be compensated with a monetary award, and the death row inmates could do one final thing for the good of humanity. There going to die anyway. just my opinion. ...TSS-2011

POLICY - RESTRICTED

CREUTZFELDT-JAKOB DISEASE: 3RD ANNUAL REPORT OF THE UK SURVEILLANCE UNIT

1. This submission, which has been agreed with colleagues in HEF(M). alerts PS(L) to the contents of the forthcoming annual report of the CJD Surveillance Unit and presents options for publication. It also highlights concern over the presentation of results which could be misrepresented by the media and others as evidence of a lilnk between CJD and the consumption of veal. ...

RECOMMENDATION

2. PS(L) is invited to agree the recommendation at para 13.

PROBLEM

7. The main findings in the case-control study were STATISTICALLY SIGNIFICANT ASSOCIATIONS BETWEEN CONSUMPTION OF VEAL OR VENISON AND THE DEVELOPMENT OF CJD (INCREASED RISKS OF 2-13x). There was also evidence of a dose-response relationship between dietary exposure and development of the disease. (Last year's findings showed an apparent association between eating black pudding and risk of CJD which was neither statistically significant nor biologically plausible - interestingly, this has not been (replicated was marked out with something i cannot read), and then this complete sentence was marked through to be replaced ;

THIS YEAR'S FINDINGS SHOW A NUMBER OF ASSOCIATIONS BUT THE STRONGEST IS FOR VEAL.

IP PS(L) wishes to probe this further we think it best to explain the matter VERBALLY. The problem is how to present the findings in this year's annual report in a way which avoids unnecessary public alarm and limits the scope for media scare stores. (or the facts...TSS)

This is of considerable concern given recent development. In particular Ministers will be particularly concerned about the European dimension given the recent troubles with the Germans.

9. DH doctors advise - and we understand Dr Wills agrees - that the association the study found between the developments of CJD and veal consumption cannot be regarded as demonstrating a causal relationship or give any reason to change the advice that eating beef and veal is safe. IF PS(L) wishes to probe this further we think it best to explain the matter verbally. The problem is how to present the findings in this year's annual report in a way which avoids unnecessary public alarm and limits the scope for media scare stories.

Next steps ...

snip... full text ;



PROBLEM

7. The main findings in the case-control study were STATISTICALLY SIGNIFICANT ASSOCIATIONS BETWEEN CONSUMPTION OF VEAL OR VENISON AND THE DEVELOPMENT OF CJD (INCREASED RISKS OF 2-13x). There was also evidence of a dose-response relationship between dietary exposure and development of the disease. (Last year's findings showed an apparent association between eating black pudding and risk of CJD which was neither statistically significant nor biologically plausible - interestingly, this has not been (replicated was marked out with something i cannot read), and then this complete sentence was marked through to be replaced ;


see watered down report here ;


Lessons from BSE

4. In retrospect, a problem of scrapie transmission in feedstuffs was perhaps predictable.


Poultry feeding and Fish farming may be particular areas worth studying...


IN CONFIDENCE

NOT FOR PUBLICATION


STRICTLY PRIVATE AND CONFIDENTIAL 25, AUGUST 1995

snip...

To minimise the risk of farmers' claims for compensation from feed compounders.

To minimise the potential damage to compound feed markets through adverse publicity.

To maximise freedom of action for feed compounders, notably by maintaining the availability of meat and bone meal as a raw material in animal feeds, and ensuring time is available to make any changes which may be required.

snip...

THE FUTURE

4..........

MAFF remains under pressure in Brussels and is not skilled at handling potentially explosive issues.

5. Tests _may_ show that ruminant feeds have been sold which contain illegal traces of ruminant protein. More likely, a few positive test results will turn up but proof that a particular feed mill knowingly supplied it to a particular farm will be difficult if not impossible.

6. The threat remains real and it will be some years before feed compounders are free of it. The longer we can avoid any direct linkage between feed milling _practices_ and actual BSE cases, the more likely it is that serious damage can be avoided. ...


Differentiation of ruminant transmissible spongiform encephalopathy isolate types, including bovine spongiform encephalopathy and CH1641 scrapie

J. G. Jacobs1, M. Sauer2, L. J. M. van Keulen1, Y. Tang2, A. Bossers1 and J. P. M. Langeveld1

1 Department of Infection Biology, Central Veterinary Institute of Wageningen UR, PO Box 65, 8200 AB Lelystad, The Netherlands 2 Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK

Correspondence J. P. M. Langeveld jan.langeveld@wur.nl

With increased awareness of the diversity of transmissible spongiform encephalopathy (TSE) strains in the ruminant population, comes an appreciation of the need for improved methods of differential diagnosis. Exposure to bovine spongiform encephalopathy (BSE) has been associated with the human TSE, variant Creutzfeldt–Jakob disease, emphasizing the necessity in distinguishing low-risk TSE types from BSE. TSE type discrimination in ruminants such as cattle, sheep, goats and deer, requires the application of several prion protein (PrP)-specific antibodies in parallel immunochemical tests on brain homogenates or tissue sections from infected animals. This study uses in a single incubation step, three PrP-specific antibodies and fluorescent Alexa dye-labelled anti-mouse Fabs on a Western blot. The usual amount of brain tissue needed is 0.5 mg. This multiplex application of antibodies directed towards three different PrP epitopes enabled differential diagnosis of all established main features of classical scrapie, BSE and Nor98-like scrapie in sheep and goats, as well as the currently known BSE types C, H and L in cattle. Moreover, due to an antibody-dependent dual PrP-banding pattern, for the first time CH1641 scrapie of sheep can be reliably discriminated from the other TSE isolate types in sheep.


Wednesday, February 16, 2011

IN CONFIDENCE

SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE


Seriously’ (YB88/6.8/4.1)
 
HB Parry Seriously’ (YB88/6.8/4.1)
 
IF the scrapie agent is generated from ovine DNA and thence causes disease in other species, then perhaps, bearing in mind the possible role of scrapie in CJD of humans (Davinpour et al, 1985), scrapie and not BSE should be the notifiable disease.
 
 
1: Neuroepidemiology. 1985;4(4):240-9.
 
Sheep consumption: a possible source of spongiform encephalopathy in humans.
 
Davanipour Z, Alter M, Sobel E, Callahan M.
 
A fatal spongiform encephalopathy of sheep and goats (scrapie) shares many characteristics with Creutzfeldt-Jakob disease (CJD), a similar dementing illness of humans. To investigate the possibility that CJD is acquired by ingestion of contaminated sheep products, we collected information on production, slaughtering practices, and marketing of sheep in Pennsylvania. The study revealed that sheep were usually marketed before central nervous system signs of scrapie are expected to appear; breeds known to be susceptible to the disease were the most common breeds raised in the area; sheep were imported from other states including those with a high frequency of scrapie; use of veterinary services on the sheep farms investigated and, hence, opportunities to detect the disease were limited; sheep producers in the area knew little about scrapie despite the fact that the disease has been reported in the area, and animal organs including sheep organs were sometimes included in processed food. Therefore, it was concluded that in Pennsylvania there are some 'weak links' through which scrapie-infected animals could contaminate human food, and that consumption of these foods could perhaps account for spongiform encephalopathy in humans. The weak links observed are probably not unique to Pennsylvania.
 
 
 
Thursday, August 20, 2015 Doctor William J. Hadlow
 
William J. Hadlow Dr. Hadlow (Ohio State ’48), 94, Hamilton, Montana, died June 20, 2015.
 
 
Spongiform Encephalopathy in Captive Wild ZOO BSE INQUIRY
 


Among ovine TSEs, classical scrapie and Nor98 were discriminated from both Norwegian moose isolates, while CH1641 samples had molecular features partially overlapping with the moose, i.e. a low MW PrPres and the presence of CTF13. In contrast, moose PrPSc did not overlap with any bovine PrPSc. Indeed, the MW of moose PrPres was lower than H-BSE and similar to C-BSE and L-BSE PrPres, but the two bovine prions lacked additional PrPres fragments. 

Conclusions: Unexpectedly, PrPSc from Norwegian moose revealed features substantially different from all other CWD isolates. The PrPSc pattern of Norwegian moose was also different from Canadian moose, suggesting that the variant PrPSc type observed does not simply reflect a host factor and could represent a new CWD strain. Furthermore, PrPSc of Norwegian moose can be easily discriminated from all BSE types, classical scrapie and Nor98, while showing significant overlapping only with CH1641. Bioassay in voles will help to clarify whether the different PrPSc types observed reflect the presence of a new CWD strain in Norwegian moose, and its relationships with known animal TSEs. 

References: 1Benestad et al, Vet Res (2016}47:88 

PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS

please see;

***Our transmission study demonstrates that CH 1641-like scrapie is likely to be more virulent than classical scrapie in cattle. 

In the US, scrapie is reported primarily in sheep homozygous for 136A/171Q (AAQQ) and the disease phenotype is similar to that seen with experimental strain CH1641.


***Our transmission study demonstrates that CH 1641-like scrapie is likely to be more virulent than classical scrapie in cattle. 

P-088 Transmission of experimental CH1641-like scrapie to bovine PrP overexpression mice

Kohtaro Miyazawa1, Kentaro Masujin1, Hiroyuki Okada1, Yuichi Matsuura1, Takashi Yokoyama2

1Influenza and Prion Disease Research Center, National Institute of Animal Health, NARO, Japan; 2Department of Planning and General Administration, National Institute of Animal Health, NARO

Introduction: Scrapie is a prion disease in sheep and goats. CH1641-lke scrapie is characterized by a lower molecular mass of the unglycosylated form of abnormal prion protein (PrpSc) compared to that of classical scrapie. It is worthy of attention because of the biochemical similarities of the Prpsc from CH1641-like and BSE affected sheep. We have reported that experimental CH1641-like scrapie is transmissible to bovine PrP overexpression (TgBoPrP) mice (Yokoyama et al. 2010). We report here the further details of this transmission study and compare the biological and biochemical properties to those of classical scrapie affected TgBoPrP mice.

Methods: The details of sheep brain homogenates used in this study are described in our previous report (Yokoyama et al. 2010). TgBoPrP mice were intracerebrally inoculated with a 10% brain homogenate of each scrapie strain. The brains of mice were subjected to histopathological and biochemical analyses.

Results: Prpsc banding pattern of CH1641-like scrapie affected TgBoPrP mice was similar to that of classical scrapie affected mice. Mean survival period of CH1641-like scrapie affected TgBoPrP mice was 170 days at the 3rd passage and it was significantly shorter than that of classical scrapie affected mice (439 days). Lesion profiles and Prpsc distributions in the brains also differed between CH1641-like and classical scrapie affected mice.

Conclusion: We succeeded in stable transmission of CH1641-like scrapie to TgBoPrP mice. Our transmission study demonstrates that CH 1641-like scrapie is likely to be more virulent than classical scrapie in cattle.

snip... 

In the US, scrapie is reported primarily in sheep homozygous for 136A/171Q (AAQQ) and the disease phenotype is similar to that seen with experimental strain CH1641.


snip...see ;






FRIDAY, NOVEMBER 08, 2019 

EFSA Panel on Biological Hazards (BIOHAZ) Update on chronic wasting disease (CWD) III 


***> cattle, pigs, sheep, cwd, tse, prion, oh my!

***> In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). 

Sheep and cattle may be exposed to CWD via common grazing areas with affected deer but so far, appear to be poorly susceptible to mule deer CWD (Sigurdson, 2008). In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). It is not known how susceptible humans are to CWD but given that the prion can be present in muscle, it is likely that humans have been exposed to the agent via consumption of venison (Sigurdson, 2008). Initial experimental research suggests that human susceptibility to CWD is low and there may be a robust species barrier for CWD transmission to humans (Sigurdson, 2008), however the risk appetite for a public health threat may still find this level unacceptable.


cwd scrapie pigs oral routes

***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <*** 

 >*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <*** 

***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). 

***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. 

This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. 

Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains. 




Friday, December 14, 2012

DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012

snip.....

In the USA, under the Food and Drug Administration's BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law.

Animals considered at high risk for CWD include:

1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and

2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.

Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.

The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.

Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.

There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.

snip.....

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011).

The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE).

Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.

snip.....

The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).

snip.....

In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.

snip.....

In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.

snip.....

Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.

snip.....


PLOS ONE Journal 

IBNC Tauopathy or TSE Prion disease, it appears, no one is sure 

Terry S. Singeltary Sr., 03 Jul 2015 at 16:53 GMT

***however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not detected using rapid tests for BSE.

***Subsequent testing resulted in the detection of pathologic lesion in unusual brain location and PrPsc detection by PMCA only.

*** IBNC Tauopathy or TSE Prion disease, it appears, no one is sure ***

http://www.plosone.org/annotation/listThread.action?root=86610

*** Singeltary reply ; Molecular, Biochemical and Genetic Characteristics of BSE in Canada Singeltary reply
 

***> READ THIS VERY, VERY, CAREFULLY, AUGUST 1997 MAD COW FEED BAN WAS A SHAM, AS I HAVE STATED SINCE 1997! 3 FAILSAFES THE FDA ET AL PREACHED AS IF IT WERE THE GOSPEL, IN TERMS OF MAD COW BSE DISEASE IN USA, AND WHY IT IS/WAS/NOT A PROBLEM FOR THE USA, and those are; 

BSE TESTING (failed terribly and proven to be a sham) 

BSE SURVEILLANCE (failed terribly and proven to be a sham) 

BSE 589.2001 FEED REGULATIONS (another colossal failure, and proven to be a sham) 

these are facts folks. trump et al just admitted it with the feed ban. 

see; 

FDA Reports on VFD Compliance 

John Maday 

August 30, 2019 09:46 AM VFD-Form 007 (640x427) 

Before and after the current Veterinary Feed Directive rules took full effect in January, 2017, the FDA focused primarily on education and outreach. ( John Maday ) Before and after the current Veterinary Feed Directive (VFD) rules took full effect in January, 2017, the FDA focused primarily on education and outreach to help feed mills, veterinarians and producers understand and comply with the requirements. Since then, FDA has gradually increased the number of VFD inspections and initiated enforcement actions when necessary. On August 29, FDA released its first report on inspection and compliance activities. The report, titled “Summary Assessment of Veterinary Feed Directive Compliance Activities Conducted in Fiscal Years 2016 – 2018,” is available online.


10 years post mad cow feed ban August 1997 

10,000,000+ LBS. of PROHIBITED BANNED MAD COW FEED I.E. BLOOD LACED MBM IN COMMERCE USA 2007 

Date: March 21, 2007 at 2:27 pm PST 

RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINES -- CLASS II PRODUCT 

Bulk cattle feed made with recalled Darling's 85% Blood Meal, Flash Dried, Recall # V-024-2007 CODE Cattle feed delivered between 01/12/2007 and 01/26/2007 RECALLING FIRM/MANUFACTURER Pfeiffer, Arno, Inc, Greenbush, WI. by conversation on February 5, 2007. 

Firm initiated recall is ongoing. 

REASON Blood meal used to make cattle feed was recalled because it was cross- contaminated with prohibited bovine meat and bone meal that had been manufactured on common equipment and labeling did not bear cautionary BSE statement. 

VOLUME OF PRODUCT IN COMMERCE 42,090 lbs. DISTRIBUTION WI 

___________________________________ 

PRODUCT Custom dairy premix products: MNM ALL PURPOSE Pellet, HILLSIDE/CDL Prot- Buffer Meal, LEE, M.-CLOSE UP PX Pellet, HIGH DESERT/ GHC LACT Meal, TATARKA, M CUST PROT Meal, SUNRIDGE/CDL PROTEIN Blend, LOURENZO, K PVM DAIRY Meal, DOUBLE B DAIRY/GHC LAC Mineral, WEST PIONT/GHC CLOSEUP Mineral, WEST POINT/GHC LACT Meal, JENKS, J/COMPASS PROTEIN Meal, COPPINI - 8# SPECIAL DAIRY Mix, GULICK, L-LACT Meal (Bulk), TRIPLE J - PROTEIN/LACTATION, ROCK CREEK/GHC MILK Mineral, BETTENCOURT/GHC S.SIDE MK-MN, BETTENCOURT #1/GHC MILK MINR, V&C DAIRY/GHC LACT Meal, VEENSTRA, F/GHC LACT Meal, SMUTNY, A- BYPASS ML W/SMARTA, 

Recall # V-025-2007 

CODE The firm does not utilize a code - only shipping documentation with commodity and weights identified. 

RECALLING FIRM/MANUFACTURER Rangen, Inc, Buhl, ID, by letters on February 13 and 14, 2007. 

Firm initiated recall is complete. 

REASON Products manufactured from bulk feed containing blood meal that was cross contaminated with prohibited meat and bone meal and the labeling did not bear cautionary BSE statement. 

VOLUME OF PRODUCT IN COMMERCE 9,997,976 lbs. DISTRIBUTION ID and NV END OF ENFORCEMENT REPORT FOR MARCH 21, 2007 

http://www.fda.gov/Safety/Recalls/EnforcementReports/2007/ucm120446.htm

PRODUCT O-NO-MORE (Formerly ORPHAN-NO-MORE) Calf Claimer Powder, packaged in 11-oz. bottles, For Animal Use Only.

Recall # V-043-2007 CODE A06 RECALLING FIRM/MANUFACTURER Springer Magrath Co., Mc Cook, NE, by telephone on January 2, 2007, fax dated January 9, 2007, by letters on February 22, 2007, March 12, March 14 and March 21, 2007.

Firm initiated recall is ongoing.

REASON The finished product was manufactured with prohibited bovine blood meal and did not bear the cautionary BSE statement that the product should not be fed to ruminants.

VOLUME OF PRODUCT IN COMMERCE

Approximately 13,255 bottles DISTRIBUTION

Nationwide

END OF ENFORCEMENT REPORT FOR JUNE 13, 2007 ###

http://www.fda.gov/Safety/Recalls/EnforcementReports/2007/ucm120458.htm

PRODUCT

Dairy cattle feed blends containing ProLak and/or ProAmino II protein concentrate, Recall # V-020-2007

CODE

All finished product manufactured from April, 3, 2006 to April 30, 2006

RECALLING FIRM/MANUFACTURER

Eatonton Co-Op Feed Company, Eatonton, GA, by letter on/about December 12, 2006. Firm initiated recall is complete.

REASON

Finished feed product was manufactured from raw feed material that may have been contaminated with ruminant derived protein.

VOLUME OF PRODUCT IN COMMERCE

25 tons

DISTRIBUTION

GA ___________________________________

END OF ENFORCEMENT REPORT FOR FEBRUARY 28, 2007

###

http://www.fda.gov/Safety/Recalls/EnforcementReports/2007/ucm120443.htm

PRODUCT

O-NO-MORE (Formerly ORPHAN-NO-MORE) Calf Claimer Powder, packaged in 9-oz. bottles, For Animal Use Only, Recall # V-011-2007

CODE

A07

RECALLING FIRM/MANUFACTURER

Springer Magrath Co., McCook, NE, by telephone on January 11, 2007 and fax on January 12, 2007. Firm initiated recall is complete.

REASON

The bovine blood meal which was used to manufacture the finished product was cross-contaminated with prohibited bovine meat and bone meal, and the finished product is not labeled with the cautionary statement that it should not be fed to ruminants.

VOLUME OF PRODUCT IN COMMERCE

300/9-oz. bottles

DISTRIBUTION

NE

END OF ENFORCEMENT REPORT FOR JANUARY 31, 2007

###

http://www.fda.gov/Safety/Recalls/EnforcementReports/2007/ucm120439.htm

BANNED MAD COW FEED IN COMMERCE IN ALABAMA 

______________________________

PRODUCT

a) EVSRC Custom dairy feed, Recall # V-130-6;

b) Performance Chick Starter, Recall # V-131-6;

c) Performance Quail Grower, Recall # V-132-6;

d) Performance Pheasant Finisher, Recall # V-133-6.

CODE

None

RECALLING FIRM/MANUFACTURER

Donaldson & Hasenbein/dba J&R Feed Service, Inc., Cullman, AL, by telephone on June 23, 2006 and by letter dated July 19, 2006. Firm initiated recall is complete.

REASON

Dairy and poultry feeds were possibly contaminated with ruminant based protein.

VOLUME OF PRODUCT IN COMMERCE

477.72 tons

DISTRIBUTION

AL 

______________________________

PRODUCT

a) Dairy feed, custom, Recall # V-134-6;

b) Custom Dairy Feed with Monensin, Recall # V-135-6.

CODE

None. Bulk product

RECALLING FIRM/MANUFACTURER

Recalling Firm: Burkmann Feed, Greeneville, TN, by Telephone beginning on June 28, 2006.

Manufacturer: H. J. Baker & Bro., Inc., Albertville, AL. Firm initiated recall is complete.

REASON

Possible contamination of dairy feeds with ruminant derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE

1,484 tons

DISTRIBUTION

TN and WV

END OF ENFORCEMENT REPORT FOR SEPTEMBER 6, 2006

###

http://www.fda.gov/Safety/Recalls/EnforcementReports/2006/ucm120418.htm

RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINE - CLASS II 

______________________________

PRODUCT

Bulk custom made dairy feed, Recall # V-115-6

CODE

None

RECALLING FIRM/MANUFACTURER

Hiseville Feed & Seed Co., Hiseville, KY, by telephone and letter on or about July 14, 2006. FDA initiated recall is ongoing.

REASON

Custom made feeds contain ingredient called Pro-Lak which may contain ruminant derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE

Approximately 2,223 tons

DISTRIBUTION

KY 

______________________________

PRODUCT

Bulk custom made dairy feed, Recall # V-116-6

CODE

None

RECALLING FIRM/MANUFACTURER

Rips Farm Center, Tollesboro, KY, by telephone and letter on July 14, 2006. FDA initiated recall is ongoing.

REASON

Custom made feeds contain ingredient called Pro-Lak which may contain ruminant derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE

1,220 tons

DISTRIBUTION

KY 

______________________________

PRODUCT

Bulk custom made dairy feed, Recall # V-117-6

CODE

None

RECALLING FIRM/MANUFACTURER

Kentwood Co-op, Kentwood, LA, by telephone on June 27, 2006. FDA initiated recall is completed.

REASON

Possible contamination of animal feed ingredients, including ingredients that are used in feed for dairy animals, with ruminant derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE

40 tons

DISTRIBUTION

LA and MS 

______________________________

PRODUCT

Bulk Dairy Feed, Recall V-118-6

CODE

None

RECALLING FIRM/MANUFACTURER

Cal Maine Foods, Inc., Edwards, MS, by telephone on June 26, 2006. FDA initiated recall is complete.

REASON

Possible contamination of animal feed ingredients, including ingredients that are used in feed for dairy animals, with ruminant derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE

7,150 tons

DISTRIBUTION

MS 

______________________________

PRODUCT

Bulk custom dairy pre-mixes, Recall # V-119-6

CODE

None

RECALLING FIRM/MANUFACTURER

Walthall County Co-op, Tylertown, MS, by telephone on June 26, 2006. Firm initiated recall is complete.

REASON

Possible contamination of dairy animal feeds with ruminant derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE

87 tons

DISTRIBUTION

MS 

______________________________

PRODUCT

Bulk custom dairy pre-mixes, Recall # V-120-6

CODE

None

RECALLING FIRM/MANUFACTURER

Ware Milling Inc., Houston, MS, by telephone on June 23, 2006. Firm initiated recall is complete.

REASON

Possible contamination of dairy animal feeds with ruminant derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE

350 tons

DISTRIBUTION

AL and MS 

______________________________

PRODUCT

a) Tucker Milling, LLC Tm 32% Sinking Fish Grower, #2680-Pellet,

50 lb. bags, Recall # V-121-6;

b) Tucker Milling, LLC #31120, Game Bird Breeder Pellet,

50 lb. bags, Recall # V-122-6;

c) Tucker Milling, LLC #31232 Game Bird Grower,

50 lb. bags, Recall # V-123-6;

d) Tucker Milling, LLC 31227-Crumble, Game Bird Starter, BMD Medicated, 50 lb bags, Recall # V-124-6;

e) Tucker Milling, LLC #31120, Game Bird Breeder, 50 lb bags, Recall # V-125-6;

f) Tucker Milling, LLC #30230, 30 % Turkey Starter, 50 lb bags, Recall # V-126-6;

g) Tucker Milling, LLC #30116, TM Broiler Finisher, 50 lb bags, Recall # V-127-6

CODE

All products manufactured from 02/01/2005 until 06/20/2006

RECALLING FIRM/MANUFACTURER

Recalling Firm: Tucker Milling LLC, Guntersville, AL, by telephone and visit on June 20, 2006, and by letter on June 23, 2006.

Manufacturer: H. J. Baker and Brothers Inc., Stamford, CT. Firm initiated recall is ongoing.

REASON

Poultry and fish feeds which were possibly contaminated with ruminant based protein were not labeled as "Do not feed to ruminants".

VOLUME OF PRODUCT IN COMMERCE

7,541-50 lb bags

DISTRIBUTION

AL, GA, MS, and TN

END OF ENFORCEMENT REPORT FOR AUGUST 9, 2006

###

http://www.fda.gov/Safety/Recalls/EnforcementReports/2006/ucm120414.htm

Subject: MAD COW FEED RECALL AL AND FL VOLUME OF PRODUCT IN COMMERCE 125 TONS Products manufactured from 02/01/2005 until 06/06/2006

Date: August 6, 2006 at 6:16 pm PST PRODUCT

a) CO-OP 32% Sinking Catfish, Recall # V-100-6;

b) Performance Sheep Pell W/Decox/A/N, medicated, net wt. 50 lbs, Recall # V-101-6;

c) Pro 40% Swine Conc Meal -- 50 lb, Recall # V-102-6;

d) CO-OP 32% Sinking Catfish Food Medicated, Recall # V-103-6;

e) "Big Jim's" BBB Deer Ration, Big Buck Blend, Recall # V-104-6;

f) CO-OP 40% Hog Supplement Medicated Pelleted, Tylosin 100 grams/ton, 50 lb. bag, Recall # V-105-6;

g) Pig Starter Pell II, 18% W/MCDX Medicated 282020, Carbadox -- 0.0055%, Recall # V-106-6;

h) CO-OP STARTER-GROWER CRUMBLES, Complete Feed for Chickens from Hatch to 20 Weeks, Medicated, Bacitracin Methylene Disalicylate, 25 and 50 Lbs, Recall # V-107-6;

i) CO-OP LAYING PELLETS, Complete Feed for Laying Chickens, Recall # 108-6;

j) CO-OP LAYING CRUMBLES, Recall # V-109-6;

k) CO-OP QUAIL FLIGHT CONDITIONER MEDICATED, net wt 50 Lbs, Recall # V-110-6;

l) CO-OP QUAIL STARTER MEDICATED, Net Wt. 50 Lbs, Recall # V-111-6;

m) CO-OP QUAIL GROWER MEDICATED, 50 Lbs, Recall # V-112-6 CODE

Product manufactured from 02/01/2005 until 06/06/2006

RECALLING FIRM/MANUFACTURER Alabama Farmers Cooperative, Inc., Decatur, AL, by telephone, fax, email and visit on June 9, 2006. FDA initiated recall is complete.

REASON Animal and fish feeds which were possibly contaminated with ruminant based protein not labeled as "Do not feed to ruminants".

VOLUME OF PRODUCT IN COMMERCE 125 tons

DISTRIBUTION AL and FL

END OF ENFORCEMENT REPORT FOR AUGUST 2, 2006

###

http://www.fda.gov/bbs/topics/enforce/2006/ENF00963.html

MAD COW FEED RECALL USA EQUALS 10,878.06 TONS NATIONWIDE Sun Jul 16, 2006 09:22 71.248.128.67

RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINE -- CLASS II 

______________________________ 

PRODUCT

a) PRO-LAK, bulk weight, Protein Concentrate for Lactating Dairy Animals, Recall # V-079-6;

b) ProAmino II, FOR PREFRESH AND LACTATING COWS, net weight 50lb (22.6 kg), Recall # V-080-6;

c) PRO-PAK, MARINE & ANIMAL PROTEIN CONCENTRATE FOR USE IN ANIMAL FEED, Recall # V-081-6;

d) Feather Meal, Recall # V-082-6 CODE

a) Bulk

b) None

c) Bulk

d) Bulk

RECALLING FIRM/MANUFACTURER H. J. Baker & Bro., Inc., Albertville, AL, by telephone on June 15, 2006 and by press release on June 16, 2006. Firm initiated recall is ongoing.

REASON

Possible contamination of animal feeds with ruminent derived meat and bone meal.

VOLUME OF PRODUCT IN COMMERCE 10,878.06 tons

DISTRIBUTION Nationwide

END OF ENFORCEMENT REPORT FOR July 12, 2006

###

http://www.fda.gov/bbs/topics/enforce/2006/ENF00960.html

what about that ALABAMA MAD COW, AND MAD COW FEED THERE FROM IN THAT STATE ???

Saturday, August 14, 2010

BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and VPSPr PRIONPATHY

*** (see mad cow feed in COMMERCE IN ALABAMA...TSS)

BANNED MAD COW FEED IN COMMERCE IN ALABAMA

Date: September 6, 2006 at 7:58 am PST PRODUCT

a) EVSRC Custom dairy feed, Recall # V-130-6;

b) Performance Chick Starter, Recall # V-131-6;

c) Performance Quail Grower, Recall # V-132-6;

d) Performance Pheasant Finisher, Recall # V-133-6.

CODE None 

RECALLING FIRM/MANUFACTURER Donaldson & Hasenbein/dba J&R Feed Service, Inc., Cullman, AL, by telephone on June 23, 2006 and by letter dated July 19, 2006. Firm initiated recall is complete.

REASON

Dairy and poultry feeds were possibly contaminated with ruminant based protein.

VOLUME OF PRODUCT IN COMMERCE 477.72 tons

DISTRIBUTION AL 
______________________________

http://www.fda.gov/bbs/topics/enforce/2006/ENF00968.html

BIO-RAD BSE TEST POLITICAL REPLY TO TSS

Subject: Re: USDA/APHIS JUNE 2004 'ENHANCED' BSE/TSE COVER UP UPDATE DECEMBER 19, 2004 USA

Date: Thu, 30 Dec 2004 12:27:06 -0600

From: "Terry S. Singeltary Sr.

BSE-L

snip...

OH, i did ask Bio-Rad about this with NO reply to date;

-------- Original Message --------

Subject: USA BIO-RADs INCONCLUSIVEs

Date: Fri, 17 Dec 2004 15:37:28 -0600

From: "Terry S. Singeltary Sr."

To: susan_berg@bio-rad.com

Hello Susan and Bio-Rad,

Happy Holidays!

I wish to ask a question about Bio-Rad and USDA BSE/TSE testing and there inconclusive. IS the Bio-Rad test for BSE/TSE that complicated, or is there most likely some human error we are seeing here?

HOW can Japan have 2 positive cows with No clinical signs WB+, IHC-, HP- , BUT in the USA, these cows are considered 'negative'?

IS there more politics working here than science in the USA?

What am I missing?

-------- Original Message --------

Subject: Re: USDA: More mad cow testing will demonstrate beef's safety

Date: Fri, 17 Dec 2004 09:26:19 -0600

From: "Terry S. Singeltary Sr."

snip...end

Experts doubt USDA's mad cow results

snip...END

WELL, someone did call me from Bio-Rad about this, however it was not Susan Berg. but i had to just about take a blood oath not to reveal there name. IN fact they did not want me to even mention this, but i feel it is much much to important. I have omitted any I.D. of this person, but thought I must document this ;

Bio-Rad, TSS phone conversation 12/28/04

Finally spoke with ;

Bio-Rad Laboratories 2000 Alfred Nobel Drive Hercules, CA 94547 Ph: 510-741-6720 Fax: 510-741-5630 Email: XXXXXXXXXXXXXXXXXX

at approx. 14:00 hours 12/28/04, I had a very pleasant phone conversation with XXXX XXXXX about the USDA and the inconclusive BSE testing problems they seem to keep having. X was very very cautious as to speak directly about USDA and it's policy of not using WB. X was very concerned as a Bio-Rad official of retaliation of some sort. X would only speak of what other countries do, and that i should take that as an answer. I told X I understood that it was a very loaded question and X agreed several times over and even said a political one.

my question;

Does Bio-Rad believe USDA's final determination of False positive, without WB, and considering the new atypical TSEs not showing positive with -IHC and -HP ???

ask if i was a reporter. i said no, i was with CJD Watch and that i had lost my mother to hvCJD. X did not want any of this recorded or repeated.

again, very nervous, will not answer directly about USDA for fear of retaliation, but again said X tell me what other countries are doing and finding, and that i should take it from there.

"very difficult to answer"

"very political"

"very loaded question"

outside USA and Canada, they use many different confirmatory tech. in house WB, SAF, along with IHC, HP, several times etc. you should see at several talks meetings (TSE) of late Paris Dec 2, that IHC- DOES NOT MEAN IT IS NEGATIVE. again, look what the rest of the world is doing.

said something about Dr. Houston stating;

any screening assay, always a chance for human error. but with so many errors (i am assuming X meant inconclusive), why are there no investigations, just false positives?

said something about ''just look at the sheep that tested IHC- but were positive''. ...

TSS

-------- Original Message --------

Subject: Your questions

Date: Mon, 27 Dec 2004 15:58:11 -0800

From: To: flounder@wt.net

Hi Terry:

............................................snip 

Let me know your phone number so I can talk to you about the Bio-Rad BSE test.

Thank you

Regards

Bio-Rad Laboratories 2000 Alfred Nobel Drive Hercules, CA 94547 Ph: 510-741-6720 Fax: 510-741-5630 Email: 

=================================

snip...end...TSS 

TSS REPORT ON 2ND TEJAS MAD COW Mon, 22 Nov 2004 17:12:15 -0600 (the one that did NOT get away, thanks to the Honorable Phyllis Fong)

-------- Original Message -------- 

Subject: Re: BSE 'INCONCLUSIVE' COW from TEXAS ???

Date: Mon, 22 Nov 2004 17:12:15 -0600

From: "Terry S. Singeltary Sr."

To: Carla Everett

References: <[log in to unmask]>

<[log in to unmask] us> 

Greetings Carla,still hear a rumor;

Texas single beef cow not born in Canada no beef entered the food chain?

and i see the TEXAS department of animal health is ramping up forsomething, but they forgot a url for update?

I HAVE NO ACTUAL CONFIRMATION YET...can you confirm???

terry

============================== ============================== 

-------- Original Message -------- 

Subject: Re: BSE 'INCONCLUSIVE' COW from TEXAS ???

Date: Fri, 19 Nov 2004 11:38:21 -0600

From: Carla Everett

To: "Terry S. Singeltary Sr."

References: <[log in to unmask]>

The USDA has made a statement, and we are referring all callers to the USDA web site. We have no information about the animal being in Texas. 

Carla At 09:44 AM 11/19/2004, you wrote:

>Greetings Carla,

>>i am getting unsubstantiated claims of this BSE 'inconclusive' cow is from

>TEXAS. can you comment on this either way please?

>>thank you,

>Terry S. Singeltary Sr.

>>

=================== =================== 

-------- Original Message -------- 

Subject: Re: BSE 'INCONCLUSIVE' COW from TEXAS ???

Date: Mon, 22 Nov 2004 18:33:20 -0600

From: Carla Everett

To: "Terry S. Singeltary Sr."

References: <[log in to unmask]>

<[log in to unmask] us>

<[log in to unmask]> 

<[log in to unmask] us> 

<[log in to unmask]>

our computer department was working on a place holder we could post USDA's announcement of any results. There are no results to be announced tonight by NVSL, so we are back in a waiting mode and will post the USDA announcement when we hear something.

At 06:05 PM 11/22/2004, you wrote: >why was the announcement on your TAHC site removed?

>>Bovine Spongiform Encephalopathy:

>November 22: Press Release title here 

>>star image More BSE information

>>>>terry

>>Carla Everett wrote:

>>>no confirmation on the U.S.' inconclusive test...

>>no confirmation on location of animal.

>>>>>>

========================== ==========================

THEN, 7+ MONTHS OF COVER-UP BY JOHANN ET AL! no doubt about it now $$$ 

NO, it's not pretty, be nice, im not pretty, but these are the facts, take em or leave em, however, you cannot change them.

with kindest regards,

I am still sincerely disgusted and tired in sunny Bacliff, Texas USA 77518

Terry S. Singeltary Sr.

FULL 130 LASHINGS TO USDA BY OIG again


FOR IMMEDIATE RELEASE

Statement

May 4, 2004

Media Inquiries: 301-827-6242

Consumer Inquiries: 888-INFO-FDA 

Statement on Texas Cow With Central Nervous System Symptoms

On Friday, April 30 th , the Food and Drug Administration learned that a cow with central nervous system symptoms had been killed and shipped to a processor for rendering into animal protein for use in animal feed.

FDA, which is responsible for the safety of animal feed, immediately began an investigation. On Friday and throughout the weekend, FDA investigators inspected the slaughterhouse, the rendering facility, the farm where the animal came from, and the processor that initially received the cow from the slaughterhouse.

FDA's investigation showed that the animal in question had already been rendered into "meat and bone meal" (a type of protein animal feed). Over the weekend FDA was able to track down all the implicated material. That material is being held by the firm, which is cooperating fully with FDA.

Cattle with central nervous system symptoms are of particular interest because cattle with bovine spongiform encephalopathy or BSE, also known as "mad cow disease," can exhibit such symptoms. In this case, there is no way now to test for BSE. But even if the cow had BSE, FDA's animal feed rule would prohibit the feeding of its rendered protein to other ruminant animals (e.g., cows, goats, sheep, bison).

FDA is sending a letter to the firm summarizing its findings and informing the firm that FDA will not object to use of this material in swine feed only. If it is not used in swine feed, this material will be destroyed. Pigs have been shown not to be susceptible to BSE. If the firm agrees to use the material for swine feed only, FDA will track the material all the way through the supply chain from the processor to the farm to ensure that the feed is properly monitored and used only as feed for pigs.

To protect the U.S. against BSE, FDA works to keep certain mammalian protein out of animal feed for cattle and other ruminant animals. FDA established its animal feed rule in 1997 after the BSE epidemic in the U.K. showed that the disease spreads by feeding infected ruminant protein to cattle.

Under the current regulation, the material from this Texas cow is not allowed in feed for cattle or other ruminant animals. FDA's action specifying that the material go only into swine feed means also that it will not be fed to poultry.

FDA is committed to protecting the U.S. from BSE and collaborates closely with the U.S. Department of Agriculture on all BSE issues. The animal feed rule provides crucial protection against the spread of BSE, but it is only one of several such firewalls. FDA will soon be improving the animal feed rule, to make this strong system even stronger.

####

http://www.fda.gov/bbs/topics/news/2004/NEW01061.html


-------- Original Message --------

Subject: Re: Congressman Henry Waxmans's Letter to the Honorable Ann Veneman on failure by USDA/APHIS TO TEST TEXAS MAD COW

Date: Wed, 9 Jun 2004 16:48:31 –0500

From: "Terry S. Singeltary Sr."

Reply-To: Bovine Spongiform Encephalopathy

To: BSE-L@uni-karlsruhe.de References: 40A8CD52.1070308@wt.net

######## Bovine Spongiform Encephalopathy #########

USA BSE RED BOOK

October 1998

BSE Red Book 2.1-36

7.2.1.7 Laboratory Coordination--The Laboratory Coordination Officer will advise the READE(3 Director concerning laboratory capabilities and appropriate laboratory examinations to be conducted to provide needed results as rapidly as possible. This individual will assist with interpretation of results.

seems that if the 'enhanced BSE/TSE testing program' is to test some 400,000+ animals in 1 1/2 years, they better hurry up, times a wasting.

BSE Red Book 2.1-39

7.6 Depopulation Procedures

Under no circumstances may BSE suspects be sent fo slaughhter or rendering.

snip...

BSE Red Book 2.1-40

7.7 Disposal Under no circumstances may BSE suspects be sent to slaughter or rendering. Notify FDA, CVM if you suspect that the carcass of a BSE-confirmed animal has moved to rendering or animal feed manufacturing. Field personel should arrange for the carcass to be transported to and examined by a qualified veterinary pathologist or field veterinary medical officer. After the pathologic examination has been completed and the necessary diagnostic specimens have been obtained, field personnel should arrange for disposal of the carcass. Before a method of disposal is selected, there are many factors that must be considered, and often other State and Federal agencies must be consulted. The environmental and legal impacts of the operation must be considered. Upon recommendation of the State or Federal agencies, VS may consider other disposal methods.

snip...

7.7.3 Rendering Because BSE is spread by rendered animal protein, BSE-suspect and confirmed carcasses must not be rendered, unless the rendered material is incinerated. Notify FDA, CVM if you suspect that dead BSE animals or carcasses have moved to rendering or animal feed manufacturing.

snip...

7.10.11 Prevention--Suspects and animals confirmed to have BSE must not be rendered. Producers, feed mills, and rendering establishments should adhere to U.S. State and local rendering policies and FDA regulations concerning the feeding of rendered animal protein to ruminants.

TSS

Terry S. Singeltary Sr. wrote:

######## Bovine Spongiform Encephalopathy #########

ONE HUNDRED EIGHTH CONGRESS CONGRESS OF THE UNITED STATES HOUSE OF REPRESENTATIVES COMMITTEE ON GOVERNMENT REFORM 2157 RAYBURN HOUSE OFFICE BUILDING WASHINGTON, DC 20515-6143

> www.house.gov/reform 

> > May 13, 2004 

> > The Honorable Ann M. Veneman Secretary of Agriculture Department of Agriculture 1400 Independence Avenue, SW Washington, DC 20250

Dear Madam Secretary:

I am writing to express concern that the recent failure of the U.S. Department of Agriculture (USDA) to test a Texas cow with neurological symptoms for bovine spongiform encephalopathy (BSE) may reflect wider problems in the surveillance program. USDA apparently does not keep track of how many cows condemned for central nervous system symptoms are tested for BSE nor does it require that suspect carcasses be held pending testing. Effective surveillance and control of BSE in the United States require a reliable system for ensuring that potentially infected cows are tested and that no infected materials enter the animal or human food supply.

Under USDA regulations, any cow that exhibits signs of central nervous system (CNS) problems must be condemned by Food Safety Inspection Service (FSIS) personnel at the plant.1 

According to a 1997 Animal and Plant Health Inspection Service (APHIS) Memorandum, brain samples all of such animals should be sent for BSE testing.2 

The memorandum notes that "[i]t is essential that brain specimens be collected from adult cattle condemned for CNS signs as part of our national surveillance of BSE."3

The cow slaughtered at the Lone Star Beef slaughterhouse last week staggered and fell, and was condemned ante mortem by FSIS personnel.4 

Despite a request from APHIS personnel at the plant to conduct BSE testing, however, an APHIS supervisor in Austin reportedly refused the test and instructed the plant to send the carcass for rendering.5

1 9 CFR 309.4.

2 USDA APHIS, Veterinary Services Memorandum No. 580.16. Procedures/or Investigation of Adult Cattle With Clinical Signs of Central Nervous System (CNS) Disease and Procedures for Surveillance of Downer Cows for Bovine Spongiform Encephalopathy (BSE) (June 11,1997). 

3 Id.

4 U.S. Confirms a Failure to Use Mad Cow Test, Wall Street Journal (May 4, 2004).

The Honorable Ann M. Veneman May 13, 2004 Page 2

This sequence of events is troubling, and it raises the question of whether this is an isolated incident. In 1997, USDA noted a major gap between the number of cattle condemned for CNS symptoms and the number of these cows actually tested for mad cow disease. The Department found:

Based on information provided by the Food Safety and Inspection Service (FSIS), the number of adult cattle (2 years of age or greater) condemned at slaughter due to CNS signs is much greater than the number whose brains have been collected for testing.6

Despite recognizing the problem more than six years ago, however, USDA apparently did not adopt procedures to ensure that these samples would be collected. In March 2004, the Government Reform Committee asked USDA to provide, for each of the last five years, the number of BSE tests performed on cattle condemned by FSIS inspectors on the basis of CNS symptoms.7 

In response, USDA provided information on the numbers of cattle condemned for CNS symptoms by FSIS, but replied that "[i]t is not possible to determine, from the data we currently collect, how many of these cattle were tested by APHIS for BSE."8 

It thus appears that not only does USDA not routinely track the gap between the number of condemned and tested cattle, but that USDA could not even calculate this gap when requested to do so by Congress.

There also appears to be a lack of clarity regarding the disposition of cattle with CNS symptoms while BSE tests are pending. In the past, companies could send cattle awaiting BSE testing results for rendering, which would allow their remains to be used in feed for animals other than ruminants, such as pigs and chickens. After this incident, both FDA and USDA policy appear to have changed — in different ways.

USDA policy has apparently shifted to requesting that companies not send cattle to rendering while awaiting test results. A May 5, 2004 memo from APHIS states, "it is requested — though not required — that [the cattle] not go to inedible rendering until the sample comes

USDA's San Angelo Vets and Techs Ordered Not to Test Suspect Cow, Meating Place (May 5, 2004).

6 USDA APHIS, supra note 2.

7 Letter from Rep. Tom Davis and Rep. Henry A- Waxman to Secretary of Agriculture Ann M. Veneman (Mar. 8, 2004).

8 Letter from Ronald F. Hicks, Assistant Administrator, Office of Program Evaluation, Enforcement, and Review- FSIS. to Reo. Henrv A. Waxman- Attachment 1 (Mar. 22- 2004).

The Honorable Ann M. Veneman May 13,2004 Page 3

back negative."9 

There is no explanation of why this course of action is requested, but not required.

FDA policy also appears to have shifted towards prohibiting the use of carcasses of cattle with CNS symptoms and indeterminate BSE status in certain types of animal feed. On April 30, FDA requested that the rendering company holding the remains of the Texas cow either destroy them or use them exclusively in swine feed. m the case that the remains are included in swine feed, FDA "will track the material all the way through the supply chain from the processor to the farm to ensure that the feed is properly monitored and used only as feed for pigs."10

Any confusion over what to do with cattle condemned for CNS symptoms awaiting testing for BSE seems unnecessary. The obvious approach is to require companies either to destroy the carcasses or hold them until test results become available. Such a policy would avoid any need for complicated traceback procedures after the discovery of a positive result. According to the information provided to the Committee by USDA, the FSIS has condemned only 200 to 250 cows per year because of signs of central nervous system damage." Mandating the destruction or holding of their carcasses would have minimal economic impact.

The experience with the BSE-infected cow in Washington State illustrates the prudence of waiting for the results of BSE tests. Prior to December 2003, USDA permitted cattle that were sampled as part of the BSE surveillance program to enter commerce even while BSE tests were pending. As a result, when the BSE-infected cow was discovered, it had already entered the food supply. This led to a complicated and partially successful traceback procedure in which hundreds of thousands of pounds of beef had to be destroyed. Because of this debacle, USDA quickly developed a new policy to require holding all carcasses from the human food chain during BSE testing.

I appreciate that you have taken steps to enhance the safety of the U.S. food supply since the discovery of BSE in the United States. I urge you to consider the lessons of this latest incident. USDA should develop a process that ensures the tracking of cattle condemned for CNS signs and should institute a policy requiring all carcasses with pending BSE tests to be destroyed or held. If there are any statutory barriers to these steps, please do not hesitate to let me know.

9 Memo from John R. Clifford, Acting Deputy Administrator, Veterinary Services, and William Smith, Assistant Administrator, Office of Field Operations, Food Safety and Inspection Service, to VSMT, Regional Directors, Area Veterinarians in Charge, and Veterinary Services, Subject: Policy Statement Regarding BSE Sampling of Condemned Cattle at Slaughter Plants - for Immediate Implementation (May 5, 2004) (online at http://www.aphis.usda.gov/lpa/issues/bse/BSE_APHIS-FSIS.pdf).

10 FDA, Statement on Cow -with Central Nervous System Symptoms (Apr. 20, 2004) (online at http://www.fda.gov/bbs/topics/news/2004/NEW01061.html).

11 The yearly totals of FSIS antemortem CNS condemnation for all adult cattle were 233 (1999), 220 (2000), 201 (2001), 249 (2002), and 247 (2003). The database for 2003 had not yet closed.

The Honorable Ann M. Veneman May 13, 2004 Page 4

Sincerely,

XXXXX X. XXXXXX

Henry A. Waxman

Ranking Minority Member

Congressman Henry Waxmans's Letter to the Honorable Ann Veneman

http://www.house.gov/reform/min/pdfs_108_2/pdfs_inves/pdf_food_usda_mad_cow_may_13_let.pdf

TSS

######### http://mailhost-alt.rz.uni-karlsruhe.de/warc/bse-l.html ##########

H. Rept. 108-815 - ACTIVITIES of the HOUSE COMMITTEE ON GOVERNMENT REFORM ONE HUNDRED EIGHTH CONGRESS FIRST AND SECOND SESSIONS 2003-2004 (Pursuant to House Rule XI, 1(d)(4)) 108th Congress (2003-2004)

snip...

After the December 23, 2003, USDA announcement of the discovery of the first U.S. case of Bovine Spongiform Encephalopathy [BSE], commonly known as ``mad cow disease,'' the committee initiated a 7-month investigation into concerns about the process for identification of BSE-infected cows and USDA's actions upon discovery of the cow. Committee investigators traveled to Washington State to interview the owner of the slaughterhouse where the BSE-infected cow was identified; requested documents from USDA; and held several meetings with USDA representatives and representatives of the cattle industry.

 As a result of the committee's investigation, USDA established written protocols to be followed in case of discovery of another BSE-infected cow. USDA also implemented an expanded BSE surveillance plan to better determine whether BSE is actually present in the U.S. cattle population, and if so, at what level. The committee held a joint hearing with the Committee on Agriculture to examine USDA's expanded surveillance plan, including concerns regarding the written protocols and management of the plan. The committee will continue to conduct oversight over USDA's surveillance plan during the 109th Congress.


THE USDA JUNE 2004 ENHANCED BSE SURVEILLANCE PROGRAM WAS TERRIBLY FLAWED ;

CDC DR. PAUL BROWN TSE EXPERT COMMENTS 2006

The U.S. Department of Agriculture was quick to assure the public earlier this week that the third case of mad cow disease did not pose a risk to them, but what federal officials have not acknowledged is that this latest case indicates the deadly disease has been circulating in U.S. herds for at least a decade.

The second case, which was detected last year in a Texas cow and which USDA officials were reluctant to verify, was approximately 12 years old.

These two cases (the latest was detected in an Alabama cow) present a picture of the disease having been here for 10 years or so, since it is thought that cows usually contract the disease from contaminated feed they consume as calves. The concern is that humans can contract a fatal, incurable, brain-wasting illness from consuming beef products contaminated with the mad cow pathogen.

"The fact the Texas cow showed up fairly clearly implied the existence of other undetected cases," Dr. Paul Brown, former medical director of the National Institutes of Health's Laboratory for Central Nervous System Studies and an expert on mad cow-like diseases, told United Press International. "The question was, 'How many?' and we still can't answer that."

Brown, who is preparing a scientific paper based on the latest two mad cow cases to estimate the maximum number of infected cows that occurred in the United States, said he has "absolutely no confidence in USDA tests before one year ago" because of the agency's reluctance to retest the Texas cow that initially tested positive.

USDA officials finally retested the cow and confirmed it was infected seven months later, but only at the insistence of the agency's inspector general.

"Everything they did on the Texas cow makes everything USDA did before 2005 suspect," Brown said. ...snip...end


CDC - Bovine Spongiform Encephalopathy and Variant Creutzfeldt ... Dr. Paul Brown is Senior Research Scientist in the Laboratory of Central Nervous System ... Address for correspondence: Paul Brown, Building 36, Room 4A-05, ...

http://www.cdc.gov/ncidod/eid/vol7no1/brown.htm

PAUL BROWN COMMENT TO ME ON THIS ISSUE

Tuesday, September 12, 2006 11:10 AM

"Actually, Terry, I have been critical of the USDA handling of the mad cow issue for some years, and with Linda Detwiler and others sent lengthy detailed critiques and recommendations to both the USDA and the Canadian Food Agency." ........TSS

THURSDAY, JANUARY 23, 2020 

USDA Consolidates Regulations for NAHLN Laboratory Testing USDA Animal and Plant Health Inspection Service sent this bulletin at 01/23/2020 02:15 PM EST


March 2019

Pennsylvania Scrapie Infected Sheep Goat Flock


WEDNESDAY, NOVEMBER 20, 2019 

Sheep Are Susceptible to the Bovine Adapted Transmissible Mink Encephalopathy agent by Intracranial Inoculation and Have Evidence of Infectivity in Lymphoid Tissues

***> ''indicating that sheep inoculated with the bovine TME agent harbor infectivity in their lymph nodes despite a lack of detection with conventional immunoassays.''


TUESDAY, APRIL 24, 2018 

ARS Research atypical Nor98 and Michigan Scrapie, CWD, CJD and mad cow feed


MONDAY, FEBRUARY 25, 2019 

MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019


MONDAY, JULY 27, 2020 

BSE Inquiry DFA's a review



TUESDAY, JUNE 30, 2020 

National Scrapie Eradication Program May 2020 Monthly Report Fiscal Year 2020 U.S. Department of Agriculture Animal and Plant Health Inspection Service Veterinary Services Strategy and Policy, Ruminant Health Center Small Ruminant Health June 15, 2020


MONDAY, JULY 27, 2020 

APHIS USDA Nor98-like scrapie was confirmed in a sheep sampled at slaughter in May 2020


TUESDAY, SEPTEMBER 22, 2020 

APHIS USDA MORE SCRAPIE ATYPICAL Nor-98 Confirmed USA September 15 2020


Terry S. Singeltary Sr.