Current as of: 2010-07-31
Date confirmed Location Animal type infected
January 21 Alberta Sheep
January 25* Ontario Sheep
February 5 Quebec Sheep
February 5* Saskatchewan Sheep
March 31 Ontario Sheep
May 12 Quebec Sheep
June 15 Alberta Sheep
July 15 Quebec Sheep
*Atypical scrapie
http://www.inspection.gc.ca/english/anima/disemala/rep/2010scrtree.shtml
WHAT does the OIE seem to think about atypical Scrapie ???
''_probably_ arises spontaneously''
''is _probably_ not contagious''
"It _appears_ that sheep affected with atypical scrapie/Nor 98 may not excrete the agent"
"and atypical scrapie/Nor 98 is _probably_ not transmissible naturally between sheep"
WITH OIE regulations based on science such as this, GOD HELP US !
nothing like putting the cart before the horse $$$
Monday, November 30, 2009
USDA AND OIE COLLABORATE TO EXCLUDE ATYPICAL SCRAPIE NOR-98 ANIMAL HEALTH CODE
http://nor-98.blogspot.com/2009/11/usda-and-oie-collaborate-to-exclude.html
Wednesday, August 11, 2010
REPORT ON THE INVESTIGATION OF THE SIXTEENTH CASE OF BOVINE SPONGIFORM ENCEPHALOPATHY (BSE) IN CANADA
http://bse-atypical.blogspot.com/2010/08/report-on-investigation-of-sixteenth.html
Subject: REPORT ON THE INVESTIGATION OF THE SEVENTEENTH CASE OF BOVINE SPONGIFORM ENCEPHALOPATHY (BSE) IN CANADA
Bovine spongiform encephalopathy (BSE) cases confirmed in Canada in 2010 BSE is a reportable disease under the Health of Animals Regulations. This means that all suspected cases must be reported to the CFIA.
The following table lists individual animals confirmed to be infected with BSE in Canada in 2010.
Current as of: 2010-07-31
Date confirmed Location Animal type infected Age of animal
February 25 Alberta Beef cow 71 months
http://www.inspection.gc.ca/english/anima/disemala/rep/2010bseesbe.shtml
It would be nice to know if this was an atypical BSE case or typical, what strain ?
It would be nice to know if again feed is the cause of this case ?
Wednesday, August 18, 2010
Incidence of CJD Deaths Reported by CJD-SS in Canada as of July 31, 2010
http://creutzfeldt-jakob-disease.blogspot.com/2010/08/incidence-of-cjd-deaths-reported-by-cjd.html
Saturday, June 5, 2010
Research Project: Transmissible Spongiform Encephalopathies: Identification of atypical scrapie in Canadian sheep
http://nor-98.blogspot.com/2010/06/research-project-transmissible.html
Let's look at some sound science on atypical Nor-98 Scrapie, shall we ;
[Although atypical scrapie is not yet ruled out, it is important to realize this is a type of scrapie that thus far has only tended to appear as a sporadic condition in older animals. Currently it has not been shown to follow the same genetic tendencies for propagation as the usual scrapie.
However, the atypical phenotypic appearance has been shown to be preserved on experimental passage.
Atypical scrapie was first identified in Norwegian sheep in 1998 and has subsequently been identified in many countries, as Australia may join that list. It is likely that this case will be sent to the UK for definitive conformation.
[Ref: M Simmons, T Konold, L Thurston, et al. BMC Veterinary Research 2010, 6:14 [provisional abstract available at
"Background ----------- "Retrospective studies have identified cases predating the initial identification of this form of scrapie, and epidemiological studies have indicated that it does not conform to the behaviour of an infectious disease, giving rise to the hypothesis that it represents spontaneous disease. However, atypical scrapie isolates have been shown to be infectious experimentally, through intracerebral inoculation in transgenic mice and sheep. [Many of the neurological diseases can be transmitted by intracerebral inoculation, which causes this moderator to approach intracerebral studies as a tool for study, but not necessarily as a direct indication of transmissibility of natural diseases. - Mod.TG]
"The 1st successful challenge of a sheep with 'field' atypical scrapie from an homologous donor sheep was reported in 2007.
"Results -------- "This study demonstrates that atypical scrapie has distinct clinical, pathological, and biochemical characteristics which are maintained on transmission and sub-passage, and which are distinct from other strains of transmissible spongiform encephalopathies in the same host genotype.
"Conclusions ------------ Atypical scrapie is consistently transmissible within AHQ homozygous sheep, and the disease phenotype is preserved on sub-passage."
Lastly, this moderator wishes to thank Terry Singletary for some of his behind the scenes work of providing citations and references for this posting. - Mod.TG]
http://www.promedmail.org/pls/otn/f?p=2400:1001:962575216785367::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,81729
Furthermore, we showed that the strain responsible for iCJD is closely related to that of one patient with sCJD, and, more unexpectedly, that these agents were similar to the French scrapie strain studied (but different from the U.S. scrapie strain). This finding requires a cautious interpretation for several reasons, not least because of the inevitably limited number of TSE strains that can be studied by such a cumbersome method as strain typing. Nonetheless, it also prompts reconsideration of the possibility that, in some instances, sheep and human TSEs can share a common origin.
snip...
http://www.pnas.org/cgi/content/full/041490898v1
P03.141
Aspects of the Cerebellar Neuropathology in Nor98
Gavier-Widén, D1; Benestad, SL2; Ottander, L1; Westergren, E1 1National Veterinary Insitute, Sweden; 2National Veterinary Institute,
Norway Nor98 is a prion disease of old sheep and goats. This atypical form of scrapie was first described in Norway in 1998. Several features of Nor98 were shown to be different from classical scrapie including the distribution of disease associated prion protein (PrPd) accumulation in the brain. The cerebellum is generally the most affected brain area in Nor98. The study here presented aimed at adding information on the neuropathology in the cerebellum of Nor98 naturally affected sheep of various genotypes in Sweden and Norway. A panel of histochemical and immunohistochemical (IHC) stainings such as IHC for PrPd, synaptophysin, glial fibrillary acidic protein, amyloid, and cell markers for phagocytic cells were conducted. The type of histological lesions and tissue reactions were evaluated. The types of PrPd deposition were characterized. The cerebellar cortex was regularly affected, even though there was a variation in the severity of the lesions from case to case. Neuropil vacuolation was more marked in the molecular layer, but affected also the granular cell layer. There was a loss of granule cells. Punctate deposition of PrPd was characteristic. It was morphologically and in distribution identical with that of synaptophysin, suggesting that PrPd accumulates in the synaptic structures. PrPd was also observed in the granule cell layer and in the white matter. The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
***The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
http://www.prion2007.com/pdf/Prion%20Book%20of%20Abstracts.pdf
PR-26
NOR98 SHOWS MOLECULAR FEATURES REMINISCENT OF GSS
R. Nonno1, E. Esposito1, G. Vaccari1, E. Bandino2, M. Conte1, B. Chiappini1, S. Marcon1, M. Di Bari1, S.L. Benestad3, U. Agrimi1 1 Istituto Superiore di Sanità, Department of Food Safety and Veterinary Public Health, Rome, Italy (romolo.nonno@iss.it); 2 Istituto Zooprofilattico della Sardegna, Sassari, Italy; 3 National Veterinary Institute, Department of Pathology, Oslo, Norway
Molecular variants of PrPSc are being increasingly investigated in sheep scrapie and are generally referred to as "atypical" scrapie, as opposed to "classical scrapie". Among the atypical group, Nor98 seems to be the best identified. We studied the molecular properties of Italian and Norwegian Nor98 samples by WB analysis of brain homogenates, either untreated, digested with different concentrations of proteinase K, or subjected to enzymatic deglycosylation. The identity of PrP fragments was inferred by means of antibodies spanning the full PrP sequence. We found that undigested brain homogenates contain a Nor98-specific PrP fragment migrating at 11 kDa (PrP11), truncated at both the C-terminus and the N-terminus, and not N-glycosylated. After mild PK digestion, Nor98 displayed full-length PrP (FL-PrP) and N-glycosylated C-terminal fragments (CTF), along with increased levels of PrP11. Proteinase K digestion curves (0,006-6,4 mg/ml) showed that FL-PrP and CTF are mainly digested above 0,01 mg/ml, while PrP11 is not entirely digested even at the highest concentrations, similarly to PrP27-30 associated with classical scrapie. Above 0,2 mg/ml PK, most Nor98 samples showed only PrP11 and a fragment of 17 kDa with the same properties of PrP11, that was tentatively identified as a dimer of PrP11. Detergent solubility studies showed that PrP11 is insoluble in 2% sodium laurylsorcosine and is mainly produced from detergentsoluble, full-length PrPSc. Furthermore, among Italian scrapie isolates, we found that a sample with molecular and pathological properties consistent with Nor98 showed plaque-like deposits of PrPSc in the thalamus when the brain was analysed by PrPSc immunohistochemistry. Taken together, our results show that the distinctive pathological feature of Nor98 is a PrP fragment spanning amino acids ~ 90-155. This fragment is produced by successive N-terminal and C-terminal cleavages from a full-length and largely detergent-soluble PrPSc, is produced in vivo and is extremely resistant to PK digestion.
*** Intriguingly, these conclusions suggest that some pathological features of Nor98 are reminiscent of Gerstmann-Sträussler-Scheinker disease.
119
http://www.neuroprion.com/pdf_docs/conferences/prion2006/abstract_book.pdf
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.
http://www.pnas.org/content/102/44/16031.abstract
Monday, December 1, 2008
When Atypical Scrapie cross species barriers
Authors
Andreoletti O., Herva M. H., Cassard H., Espinosa J. C., Lacroux C., Simon S., Padilla D., Benestad S. L., Lantier F., Schelcher F., Grassi J., Torres, J. M., UMR INRA ENVT 1225, Ecole Nationale Veterinaire de Toulouse.France; ICISA-INlA, Madrid, Spain; CEA, IBiTec-5, DSV, CEA/Saclay, Gif sur Yvette cedex, France; National Veterinary Institute, Postboks 750 Sentrum, 0106 Oslo, Norway, INRA IASP, Centre INRA de Tours, 3738O Nouzilly, France.
Content
Atypical scrapie is a TSE occurring in small ruminants and harbouring peculiar clinical, epidemiological and biochemical properties. Currently this form of disease is identified in a large number of countries. In this study we report the transmission of an atypical scrapie isolate through different species barriers as modeled by transgenic mice (Tg) expressing different species PRP sequence.
The donor isolate was collected in 1995 in a French commercial sheep flock. inoculation into AHQ/AHQ sheep induced a disease which had all neuro-pathological and biochemical characteristics of atypical scrapie. Transmitted into Transgenic mice expressing either ovine or PrPc, the isolate retained all the described characteristics of atypical scrapie.
Surprisingly the TSE agent characteristics were dramatically different v/hen passaged into Tg bovine mice. The recovered TSE agent had biological and biochemical characteristics similar to those of atypical BSE L in the same mouse model. Moreover, whereas no other TSE agent than BSE were shown to transmit into Tg porcine mice, atypical scrapie was able to develop into this model, albeit with low attack rate on first passage.
Furthermore, after adaptation in the porcine mouse model this prion showed similar biological and biochemical characteristics than BSE adapted to this porcine mouse model. Altogether these data indicate.
(i) the unsuspected potential abilities of atypical scrapie to cross species barriers
(ii) the possible capacity of this agent to acquire new characteristics when crossing species barrier
These findings raise some interrogation on the concept of TSE strain and on the origin of the diversity of the TSE agents and could have consequences on field TSE control measures.
http://www.neuroprion.org/resources/pdf_docs/conferences/prion2008/abstract-book-prion2008.pdf
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease Are Encoded by Distinct Prion Types
http://nor-98.blogspot.com/2009/12/similarities-between-forms-of-sheep.html
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease Are Encoded by Distinct Prion Types
(hmmm, this is getting interesting now...tss)
Sporadic CJD type 1 and atypical/ Nor98 scrapie are characterized by fine (reticular) deposits,
see also ;
All of the Heidenhain variants were of the methionine/ methionine type 1 molecular subtype.
http://cjdusa.blogspot.com/2009/09/co-existence-of-scrapie-prion-protein.html
see full text ;
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease Are Encoded by Distinct Prion Types
http://nor-98.blogspot.com/2009/12/similarities-between-forms-of-sheep.html
Epidemiology of Scrapie in the United States 1977
http://web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
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. ...
http://collections.europarchive.org/tna/20090505194948/http://bseinquiry.gov.uk/files/yb/1988/06/08004001.pdf
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. ........
http://web.archive.org/web/20030517224223/http://www.bseinquiry.gov.uk/files/yb/1994/02/07002001.pdf
another outbreak of spontaneous atypical scrapie ???
Sunday, March 28, 2010
Atypical/Nor98 scrapie in the Basque Country: a case report of eight outbreaks
FURTHER INTO THIS STUDY ;
Case presentation
Between 2002 and 2008 the mean number of sheep analysed per year in the Basque Country was 764 and until September 2009, the total number of animals screened added up to 5620. Of these, eight Latxa ewes with molecular and pathological features of AS/Nor98 were found. The cases were detected widely distributed within this region and amounted to a significantly (p=0.0196) higher prevalence (0.15 %) than that of classical scrapie (0.02 %) (Table 1).
http://nor-98.blogspot.com/2010/03/atypicalnor98-scrapie-in-basque-country.html
MONEY will buy anything $$$
In 2009, the World Animal Health Organization (OIE) recognized Nor98-like scrapie as a separate disease from classical scrapie because of differences in laboratory findings, transmissibility, and distribution. This determination means that Nor98-like scrapie is not a reportable disease to OIE, and should be of no trade concern.
How has APHIS’ policy changed regarding Nor98-like scrapie?
APHIS will no longer require the depopulation or movement restriction of Nor98-like scrapie exposed sheep and goats. APHIS will propose changes to the Code of Federal Regulations (CFR) in 2010 to allow the APHIS Administrator to eliminate or reduce post exposure requirements for certain scrapie types (or certain/specific types of scrapie)-- such as Nor98-like scrapie -- that are determined to pose minimal risk of lateral transmission under natural conditions.
http://www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/nor98-like_information.pdf
SCRAPIE The United States is unable to support the proposed new draft Code Chapter on Scrapie. The draft chapter, as written, departs significantly from the existing chapter, is confusing and is difficult to understand.
This version of the scrapie chapter uses much of the same wording as the BSE chapter and is written as if the predominance of evidence revealed that scrapie was a food-borne disease similar to BSE in cattle which is inappropriate.
Moreover, several of the new changes are not supported by current scientific evidence.
As a result, detailed comments on individual articles would not meaningful at this time.
The United States is not supportive of the proposed draft chapter for the following reasons:
1. Inclusion of “atypical” scrapie: The scientific evidence indicates that “atypical” scrapie, also referred to as Nor-98, Nor-98-like, or non-classical scrapie, is not the same disease as classical scrapie. Further, “atypical” scrapie does not meet the criteria for listing diseases of trade concern by the OIE, as described in Chapter 2.1.1 of the Code. The United States recommends that the scope of this chapter be limited to classical scrapie in sheep and goats. Further, the United States recommends that OIE clearly adopt the position that “atypical” scrapie represents a distinct disease entity from classical scrapie and that it not be a listed disease.
• There is no evidence that “atypical” scrapie is a contagious disease. If it is contagious, available evidence suggests that it has a much lower transmission efficiency. (Hopp, et al, 2006; Green, et al, 2007; Benestad, et al 2008; McIntyre, et al, 2008)
• The disease appears to be ubiquitous in that it has been found wherever sufficient surveillance has been conducted. (Buschmann et al, 2004; De Bosschere et al, 2004; Orge, et al, 2004; Everest et al, 2006; Arsac, 2007; Benestad, et al 2008; Fediaevsky, et al, 2008)
• The disease does not appear to be economically significant in that the prevalence of clinical disease is low and it typically occurs in older animals. (Luhken, et al., 2007; Benestad, et al 2008).
• The disease is as likely as not to be the result of a spontaneous conversion of normal prion protein. (Benestad, et al 2008, De Bosschere et al 2007)
• Removal of exposed sheep is unlikely to reduce the prevalence of “atypical” scrapie infection and removing only those exposed sheep that are phenylalanine (F) at codon 141 is scientifically unsound since the disease is known to affect sheep of most other genotypes. Further, sheep with AHQ alleles have a similar risk of infection with “atypical” strains as sheep with F at codon 141. (Luhken, et al., 2007).
• If “atypical” scrapie is included as a listed disease, the surveillance and diagnostic requirements which are needed to identify these cases should be described in detail in both this Chapter and the Manual of Diagnostic Tests and Vaccines for Terrestrial 2 Animals. Data from Europe illustrates that using the proper test(s) is essential for the identification of atypical scrapie (Fediaevsky et al., 2008).
SNIP...
6. Overemphasis on importation and use of bovine meat and bone meal as a route of scrapie transmission: Given that the draft Chapter is not intended to address risk mitigation for BSE in small ruminants, we believe there is an over-emphasis on this potential route of transmission in the current draft. The United States recommends that the requirements in this chapter be limited to the inclusion of products from sheep and goats (instead of from all ruminants) in feed or feed ingredients intended for consumption by animals
• The use of products from sheep and goats as feed or feed ingredients for ruminant or non-ruminant animals represent one possible route of transmission (Philippe, et al, 2005) and a source of environmental contamination with the classical scrapie agent. However, this is not the primary route of transmission for the scrapie agent.
• The need for the exclusion of cattle-derived protein or other animal protein to mitigate BSE risk should be based on a country’s BSE risk status and should be addressed in Chapter 2.3.13 of the Code.
SNIP...
14. Failure to provide scientific justification for the list of permitted commodities in Item 1 of Article 2.4.8.1. . We recommend that the list be re-evaluated and those items that have not been substantiated as presenting no risk be excluded or those with some risk but where the intended use mitigates the risk the use be specified.
• There is no known human health risk associated with scrapie. As such, if meat and meat products for human consumption are included in this list, sheep and/or goat milk intended for human consumption should also be added to the list of permitted commodities in Item 1 of Article 2.4.8.1.
• In the vast majority of sheep infected with classical scrapie, actual infectivity or PrPres has been identified in most tissues including the lymphoreticular system (tonsils, spleen, lymph nodes), the gastrointestinal tract, brain, and spinal cord (Hadlow et. al. 1979; Hadlow et al., 1980; van Kuelen et al., 1996; van Kuelen et al., 1999, Andreoletti et al., 2000; Heggebø et al., 2002; Caplazi et al., 2004). Infectivity and/or PrPres has also been identified in the placenta (see Hourrigan et al., 1979; Onodera et al., 1993; Pattison et al., 1972; Pattison et al., 1974; Race et al., 1998), blood (Hunter et al., 2002; Houston et al. 2008); peripheral nerves (Groschup et al., 1996), muscle (Pattison and Millson, 1962; Andreoletti et al., 2004; Casalone et al., 2005), salivary gland (Hadlow et al., 1980; Vascellari et al., 2007), kidney (Siso et al., 2006), and skin ( Thomzig et al., 2007). In addition, recent work has shown milk and/or colostrum from scrapie infected ewes transmitted the disease to 17 of 18 lambs (Konold et al., 2008).
• The data on the risk of low protein tallow made from scrapie infected tissues particularly for use in milk replacer is limited and some epidemiologic studies suggest an association of milk replacer use with scrapie risk. Taylor et al., 1997 examined the inactivation capacity of different rendering system in regards to scrapie. The presence of infectivity was determined by bioassay into mice. From the onset of this study, it was assumed that tallow was not the vehicle for the transmission of TSE. Hence only 2 tallow samples were examined.
http://www.aphis.usda.gov/import_export/animals/oie/downloads/tahc_mar-sep08/tahc-scrapie-77-mar08_cmt.pdf
USDA's Deputy Secretary Talks with Sheep Producers
May 1, 2009 -
snip...
According to Jere Dick, DVM, associate deputy administrator and chief of field operations for the Animal and Plant Health Inspection Service (APHIS), "We anticipate discussions and hopefully revisions of the scrapie chapter at the World Organization for Animal Health meeting this month. The revisions will likely exclude Nor-98 like scrapie from classical scrapie regulations. If this is done, APHIS will be able to exempt flocks with Nor-98 like scrapie cases, should they occur, from extensive flock depopulation actions."
snip...end
http://sheepusa.org/?page=site/newsandevents&nav_id=c806da768c6fcc2652eee0967bc96b5a#772efce63bd783bb5da167cf744f349a
Sunday, March 28, 2010
Nor-98 atypical Scrapie, atypical BSE, spontaneous TSE, trade policy, sound science ?
http://nor-98.blogspot.com/2010/03/nor-98-atypical-scrapie-atypical-bse.html
URGENT DATA ON ATYPICAL BSE RISK FACTORS TO HUMANS AND ANIMALS OIE REFUSE TO ACKNOWLEDGE $
position: Post Doctoral Fellow Atypical BSE in Cattle
Closing date: December 24, 2009
Anticipated start date: January/February 2010
Employer: Canadian and OIE Reference Laboratories for BSE CFIA Lethbridge Laboratory, Lethbridge/Alberta
snip...
To date the OIE/WAHO assumes that the human and animal health standards set out in the BSE chapter for classical BSE (C-Type) applies to all forms of BSE which include the H-type and L-type atypical forms. This assumption is scientifically not completely justified and accumulating evidence suggests that this may in fact not be the case. Molecular characterization and the spatial distribution pattern of histopathologic lesions and immunohistochemistry (IHC) signals are used to identify and characterize atypical BSE. Both the L-type and H-type atypical cases display significant differences in the conformation and spatial accumulation of the disease associated prion protein (PrPSc) in brains of afflicted cattle. Transmission studies in bovine transgenic and wild type mouse models support that the atypical BSE types might be unique strains because they have different incubation times and lesion profiles when compared to C-type BSE. When L-type BSE was inoculated into ovine transgenic mice and Syrian hamster the resulting molecular fingerprint had changed, either in the first or a subsequent passage, from L-type into C-type BSE. In addition, non-human primates are specifically susceptible for atypical BSE as demonstrated by an approximately 50% shortened incubation time for L-type BSE as compared to C-type. Considering the current scientific information available, it cannot be assumed that these different BSE types pose the same human health risks as C-type BSE or that these risks are mitigated by the same protective measures.
http://www.prionetcanada.ca/detail.aspx?menu=5&dt=293380&app=93&cat1=387&tp=20&lk=no&cat2
Sunday, April 4, 2010
USDA AND OIE OUT OF TOUCH WITH RISK FACTOR ON ATYPICAL TSE
http://bseusa.blogspot.com/2010/04/usda-and-oie-out-of-touch-with-risk.html
Monday, April 5, 2010
Update on Feed Enforcement Activities to Limit the Spread of BSE April 5, 2010
http://madcowfeed.blogspot.com/2010/04/update-on-feed-enforcement-activities.html
Wednesday, March 3, 2010
NOR-98 ATYPICAL SCRAPIE USA 4 CASES DETECTED JANUARY 2010
http://nor-98.blogspot.com/2010/03/nor-98-atypical-scrapie-usa-4-cases.html
Thursday, January 07, 2010
Scrapie and Nor-98 Scrapie November 2009 Monthly Report Fiscal Year 2010 and FISCAL YEAR 2008
http://scrapie-usa.blogspot.com/2010/01/scrapie-and-nor-98-scrapie-november.html
Monday, August 9, 2010
National Prion Disease Pathology Surveillance Center Cases Examined (July 31, 2010)
http://prionunitusaupdate2008.blogspot.com/2010/08/national-prion-disease-pathology.html
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
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Sunday, April 18, 2010
SCRAPIE AND ATYPICAL SCRAPIE TRANSMISSION STUDIES A REVIEW 2010
http://scrapie-usa.blogspot.com/2010/04/scrapie-and-atypical-scrapie.html
TSS
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