Monday, April 25, 2011

Experimental Oral Transmission of Atypical Scrapie to Sheep

Volume 17, Number 5–May 2011

Research

Experimental Oral Transmission of Atypical Scrapie to Sheep


Marion M. Simmons, S. Jo Moore,1 Timm Konold, Lisa Thurston, Linda A. Terry, Leigh Thorne, Richard Lockey, Chris Vickery, Stephen A.C. Hawkins, Melanie J. Chaplin, and John Spiropoulos –Weybridge, Addlestone, UK

Suggested citation for this article

Abstract To investigate the possibility of oral transmission of atypical scrapie in sheep and determine the distribution of infectivity in the animals' peripheral tissues, we challenged neonatal lambs orally with atypical scrapie; they were then killed at 12 or 24 months. Screening test results were negative for disease-specific prion protein in all but 2 recipients; they had positive results for examination of brain, but negative for peripheral tissues. Infectivity of brain, distal ileum, and spleen from all animals was assessed in mouse bioassays; positive results were obtained from tissues that had negative results on screening. These findings demonstrate that atypical scrapie can be transmitted orally and indicate that it has the potential for natural transmission and iatrogenic spread through animal feed. Detection of infectivity in tissues negative by current surveillance methods indicates that diagnostic sensitivity is suboptimal for atypical scrapie, and potentially infectious material may be able to pass into the human food chain.



SNIP...


Discussion This study is still ongoing and will not be completed until 2012. However, the current interim report documents the successful oral transmission of atypical scrapie, confirms that the disease phenotype is retained following transmission by this route in AHQ/AHQ sheep, and indicates that infectivity can be demonstrated in the gut in the absence of detectable PrPSc at least as early as 12 months after exposure.

One sheep (animal 12) culled at 24 months post inoculation displayed abnormalities in behavior and movement suggestive of atypical scrapie. Signs like ataxia with head tremor and circling have been described in experimental (19) and natural (3,30) disease, which was attributed to lesions in the cerebellum and forebrain, respectively, corresponding with PrPSc accumulation in these areas (20,24).

By contrast, animal 11, which had confirmed atypical scrapie based on postmortem tests, was considered clinically normal. The less severe and limited PrPSc accumulation in the brain of this sheep than in animal 12 may explain the absence of clinical abnormalities, which is supported by our findings in goats with scrapie in which more extensive PrPSc accumulation in the brain was usually associated with a more severe clinical disease (25).

Although all TSEs are transmissible after intracerebral challenge to a susceptible host, only some are infectious under natural conditions. Therefore, it was important from a pathogenesis and disease control perspective to establish whether or not oral transmission can be successful. However, the challenge model in this study exposed animals as neonates, when the esophageal groove is operational and the lambs are physiologically monogastric. Exposure of 3-month-old ruminating animals to similar amounts of positive brain by the oral route have so far not resulted in any clinical disease, with all animals still alive >1,500 days post challenge (M.M. Simmons, unpub. data), but most natural cases have been recorded in animals older than this, so these animals may still progress to disease in the next few years. Since this challenge study in older animals has no time-kill component, and no losses caused by unrelated disease have occurred, whether any of these sheep are in a preclinical phase of disease is unknown. Unfortunately, the absence of detectable PrPSc in lymphoreticular tissues of sheep with atypical scrapie precludes the use of biopsies to ascertain early infection in these animals.

Transmission may be more efficient in newborn animals; the incubation periods of sheep orally infected with classical scrapie were significantly shorter in sheep challenged at 14 days of age than those challenged at 6 months of age (31). If, however, oral transmission is only effective in such young animals, then field exposure would most likely have to be through milk, which is known to be a highly effective route of transmission for classical scrapie (32). No data are currently available on the potential infectivity of milk from animals with atypical scrapie.

Successful oral transmission also raises questions regarding the pathogenesis of this form of disease. There must be passage of the infectious agent from the alimentary canal to the brain through one of several possible routes, most likely those that have been suggested and discussed in detail for other TSEs, for example, retrograde neuronal transportation either directly (33–35) or through lymphoid structures or hematogenously (36). Infectivity in the absence of readily demonstrable PrPSc has been reported (37–39), and although the mouse bioassay may detect evidence of disease in other tissues, these data may not be available for at least another 2 years. More protease-sensitive forms of PrPSc may be broken down more efficiently within cells and thus do not accumulate in peripheral tissues (19), enabling atypical PrPSc to transit the digestive tract and disseminate through other systems in small amounts before accumulating detectably in the central nervous system.

Although we do not have epidemiologic evidence that supports the efficient spread of disease in the field, these data imply that disease is potentially transmissible under field situations and that spread through animal feed may be possible if the current feed restrictions were to be relaxed. Additionally, almost no data are available on the potential for atypical scrapie to transmit to other food animal species, certainly by the oral route. However, work with transgenic mice has demonstrated the potential susceptibility of pigs, with the disturbing finding that the biochemical properties of the resulting PrPSc have changed on transmission (40). The implications of this observation for subsequent transmission and host target range are currently unknown.

How reassuring is this absence of detectable PrPSc from a public health perspective? The bioassays performed in this study are not titrations, so the infectious load of the positive gut tissues cannot be quantified, although infectivity has been shown unequivocally. No experimental data are currently available on the zoonotic potential of atypical scrapie, either through experimental challenge of humanized mice or any meaningful epidemiologic correlation with human forms of TSE. However, the detection of infectivity in the distal ileum of animals as young as 12 months, in which all the tissues tested were negative for PrPSc by the currently available screening and confirmatory diagnostic tests, indicates that the diagnostic sensitivity of current surveillance methods is suboptimal for detecting atypical scrapie and that potentially infectious material may be able to pass into the human food chain undetected.


http://www.cdc.gov/eid/content/17/5/848.htm?source=govdelivery






Increased Atypical Scrapie Detections

Press reports indicate that increased surveillance is catching what otherwise would have been unreported findings of atypical scrapie in sheep. In 2009, five new cases have been reported in Quebec, Ontario, Alberta, and Saskatchewan. With the exception of Quebec, all cases have been diagnosed as being the atypical form found in older animals. Canada encourages producers to join its voluntary surveillance program in order to gain scrapie-free status. The World Animal Health will not classify Canada as scrapie-free until no new cases are reported for seven years. The Canadian Sheep Federation is calling on the government to fund a wider surveillance program in order to establish the level of prevalence prior to setting an eradication date. Besides long-term testing, industry is calling for a compensation program for farmers who report unusual deaths in their flocks.

http://gain.fas.usda.gov/Recent%20GAIN%20Publications/This%20Week%20in%20Canadian%20Agriculture%20%20%20%20%20Issue%2028_Ottawa_Canada_11-6-2009.pdf






SCRAPIE USA UPDATE FEBRUARY 2011

Positive Scrapie Cases

As of February 28, 2011, 11 cases of classical scrapie and 1 case of Nor98-like scrapie were confirmed by the National Veterinary Services Laboratories (NVSL); 6 of the positive cases were Regulatory Scrapie Slaughter Surveillance (RSSS) cases (collected between October 1, 2010 and February 28, 2011 and confirmed by March 10, 2011), and 6 were field cases including 1 positive goat (Figure 7). With this positive, 22 cases of scrapie in goats have been confirmed by NVSL since implementation of the regulatory changes in FY 2002 (Figure 8).

http://www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/monthly_scrapie_rpt.ppsx






p.s. please note another new case of the atypical Nor-98 Scrapie in the USA, this time in California. ...TSS



National Scrapie Surveillance Plan United States Department of Agriculture Animal and Plant Health Inspection Service Veterinary Services Centers for Epidemiology and Animal Health National Surveillance Unit Fort Collins, CO September 2010

snip...

it is believed that eradication of nonclassical scrapie from the United States is neither necessary nor feasible.

snip...

http://www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/national_scrapie_surv_plan.pdf





Monday, March 21, 2011

Sheep and Goat BSE Propagate More Efficiently than Cattle BSE in Human PrP Transgenic Mice

snip...

On the other hand, this component would not be distinguishable from bovine-passaged BSE prions due to the current limits of the standard biological methods and/or the molecular tools employed here to characterize prion strains. Whatever the mechanism, the notion that a passage through an intermediate species can profoundly alter prion virulence for the human species has important public-health issues, regarding emerging and/or expanding TSEs, like atypical scrapie or CWD.

snip...

Taken all together, our results suggest that the possibility of a small ruminant BSE prion as vCJD causal agent could not be ruled out, which has important implications on public and animal health policies. On one hand, although the exact magnitude and characteristic of the vCJD epidemic is still unclear, its link with cattle BSE is supported by strong epidemiological ground and several experimental data. On the other hand, the molecular typing performed in our studies, indicates that the biochemical characteristics of the PrPres detected in brains of our sheep and goat BSE-inoculated mice seem to be indistinguishable from that observed in vCJD. Considering the similarity in clinical manifestation of BSE- and scrapie-affected sheep [48], a masker effect of scrapie over BSE, as well as a potential adaptation of the BSE agent through subsequent passages, could not be ruled out. As BSE infected sheep PrPSc have been detected in many peripheral organs, small ruminant-passaged BSE prions might be a more widespread source of BSE infectivity compared to cattle [19], [49], [50]. This fact is even more worrying since our transmission studies suggest that apparently Met129 human PrP favours a BSE agent with ovine rather than a bovine sequence. Finally, it is evident that, although few natural cases have been described and so far we cannot draw any definitive conclusion about the origin of vCJD, we can not underestimate the risk of a potential goat and/or sheep BSE agent.

snip...


http://nor-98.blogspot.com/2011/03/sheep-and-goat-bse-propagate-more.html





Technical Abstract:

Prion strains may vary in their ability to transmit to humans and animals. Few experimental studies have been done to provide evidence of differences between U.S. strains of scrapie, which can be distinguished by incubation times in inbred mice, microscopic lesions, immunoreactivity to various antibodies, or molecular profile (electrophoretic mobility and glycoform ratio). Recent work on two U.S. isolates of sheep scrapie supports that at least two distinct strains exist based on differences in incubation time and genotype of sheep affected. One isolate (No. 13-7) inoculated intracerebrally caused scrapie in sheep AA at codon 136 (AA136) and QQ at codon 171 (QQ171) of the prion protein in an average of 19 months post-inoculation (PI) whereas a second isolate (No. x124) caused disease in less than 12 months after oral inoculation in AV136/QQ171 sheep. Striking differences were evident when further strain analysis was done in R111, VM, C57Bl6, and C57Bl6xVM (F1) mice. No. 13-7 did not induce disease in any mouse strain at any time post-inoculation (PI) nor were brain tissues positive by western blot (WB). Positive WB results were obtained from mice inoculated with isolate No. x124 starting at day 380 PI. Incubation times averaged 508, 559, 601, and 633 days PI for RIII, C57Bl6, VM, and F1 mice, respectively. Further passage will be required to characterize these scrapie strains in mice. This work provides evidence that multiple scrapie strains exist in U.S. sheep.


http://www.ars.usda.gov/research/publications/publications.htm?seq_no_115=227516






One of these isolates (TR316211) behaved like the CH1641 isolate, with PrPres features in mice similar to those in the sheep brain. From two other isolates (O100 and O104), two distinct PrPres phenotypes were identified in mouse brains, with either high (h-type) or low (l-type) apparent molecular masses of unglycosylated PrPres, the latter being similar to that observed with CH1641, TR316211, or BSE. Both phenotypes could be found in variable proportions in the brains of the individual mice. In contrast with BSE, l-type PrPres from "CH1641-like" isolates showed lower levels of diglycosylated PrPres. From one of these cases (O104), a second passage in mice was performed for two mice with distinct PrPres profiles. This showed a partial selection of the l-type phenotype in mice infected with a mouse brain with predominant l-type PrPres, and it was accompanied by a significant increase in the proportions of the diglycosylated band. These results are discussed in relation to the diversity of scrapie and BSE strains.


http://jvi.asm.org/cgi/content/full/81/13/7230?view=long&pmid=17442721





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.


http://www.ars.usda.gov/research/publications/publications.htm?seq_no_115=182469





Wednesday, February 16, 2011

IN CONFIDENCE SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE


Wednesday, February 16, 2011 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.


http://collections.europarchive.org/tna/20080102222950/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf





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


http://collections.europarchive.org/tna/20040904150726/http://www.bseinquiry.gov.uk/files/yb/1990/09/26003001.pdf




http://web.archive.org/web/20031028205208/www.bseinquiry.gov.uk/files/yb/1990/08/28002001.pdf




http://web.archive.org/web/20030822170317/www.bseinquiry.gov.uk/files/yb/1990/11/01005001.pdf





SNIP...SEE FULL TEXT ;



http://scrapie-usa.blogspot.com/2011/02/in-confidence-scrapie-transmission-to.html





Friday, February 11, 2011

Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues

snip...

The presence of infectivity in peripheral tissues that enter the food chain clearly indicates that the risk of dietary exposure to Atypical/Nor98 scrapie cannot be disregarded. However, according to our observations, in comparison to the brain, the infectious titres in the peripheral tissues were five log10 lower in Atypical/Nor98 scrapie than in classical scrapie. Therefore, the reduction of the relative exposure risk following SRM removal (CNS, head, spleen and ileum) is probably significantly higher in Atypical/Nor98 scrapie cases than in classical scrapie cases. However, considering the currently estimated prevalence of Atypical/Nor98 scrapie in healthy slaughtered EU population [10], it is probable that atypical scrapie infectivity enters in the food chain despite the prevention measures in force.

Finally, the capacity of Atypical/Nor98 scrapie agent (and more generally of small ruminants TSE agents) to cross species barrier that naturally limits the transmission risk is insufficiently documented. Recently, the transmission of an Atypical/Nor98 scrapie isolate was reported into transgenic mice over-expressing the porcine PrP [47]. Such results cannot directly be extrapolated to natural exposure conditions and natural hosts. However, they underline the urgent need for further investigations on the potential capacity of Atypical/Nor98 scrapie to propagate in other species than small ruminants.

snip...please see full text thanks to the Authors and plospathogens.org/

http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1001285;jsessionid=CECDA9978AB8F920FB2ED52F4EB71071.ambra01





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]

The HealthMap/ProMED-mail interactive map of Australia is available at . - Sr.Tech.Ed.MJ]

http://www.promedmail.org/pls/otn/f?p=2400:1001:962575216785367::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,81729





Scrapie

The two Commissions discussed the issue of ‘atypical’ scrapie in terms of notification requirements and the issue of the host genetic resistance. In response to questions of Members, the Code Commission clarified that ‘classical’ scrapie is reportable to the OIE but that ‘atypical’ scrapie is not reportable (in accordance with the recommendations made by the ad hoc Group on Atypical Scrapie and Atypical BSE, which met in November 2007). However, the sharing of scientific information on ‘atypical’ scrapie is encouraged. At this time, the Code Commission considered that more scientific information would be needed to fully address the issues associated with host genotype.

EU comment

4

OIE Terrestrial Animal Health Standards Commission / September 2010

The EU takes note of the fact that atypical scrapie is not an OIE listed disease. Nevertheless, it will remain notifiable in the EU. Moreover it must be stressed that any emergence of this disease should be notified to the OIE by Members and that scientific data should continue to be gathered.

snip...

Zoonotic Potential

Has transmission to humans been proven? (with the exception of artificial

circumstances) AND

Is human infection associated with severe consequences? (death or prolonged illness)

http://ec.europa.eu/food/international/organisations/docs/EU_comments_OIE_terrestrial_animal_health_code_en.pdf





snip...

http://nor-98.blogspot.com/2011/02/atypicalnor98-scrapie-infectivity-in.html





Sunday, December 12, 2010

EFSA reviews BSE/TSE infectivity in small ruminant tissues News Story 2 December 2010

http://transmissiblespongiformencephalopathy.blogspot.com/2010/12/efsa-reviews-bsetse-infectivity-in.html





Monday, November 22, 2010

Atypical transmissible spongiform encephalopathies in ruminants: a challenge for disease surveillance and control

REVIEW ARTICLES

http://transmissiblespongiformencephalopathy.blogspot.com/2010/11/atypical-transmissible-spongiform.html





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





Wednesday, January 19, 2011

EFSA and ECDC review scientific evidence on possible links between TSEs in animals and humans Webnachricht 19 Januar 2011

http://transmissiblespongiformencephalopathy.blogspot.com/2011/01/efsa-and-ecdc-review-scientific.html





Tuesday, January 18, 2011

Agent strain variation in human prion disease: insights from a molecular and pathological review of the National Institutes of Health series of experimentally transmitted disease

http://transmissiblespongiformencephalopathy.blogspot.com/2011/01/agent-strain-variation-in-human-prion.html





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/20010305222246/www.bseinquiry.gov.uk/files/yb/1994/02/07002001.pdf





RISK OF BSE TO SHEEP VIA FEED

http://collections.europarchive.org/tna/20090114022605/http://www.bseinquiry.gov.uk/files/sc/seac31/tab01.pdf





Marion Simmons communicated surprising evidence for oral transmissibility of Nor98/atypical scrapie in neonatal sheep and although bioassay is ongoing, infectivity of the distal ileum of 12 and 24 month infected sheep is positive in Tg338 mice.

http://www.goatbse.eu/site/index.php?option=com_content&view=article&id=94:minutes-workshop-2010&catid=9:popular&Itemid=22





SUMMARY REPORTS OF MAFF BSE TRANSMISSION STUDIES AT THE CVL ;

http://collections.europarchive.org/tna/20090114023010/http://www.bseinquiry.gov.uk/files/sc/seac18/tab02b.pdf





THE RISK TO HUMANS FROM SHEEP;

http://collections.europarchive.org/tna/20090114022915/http://www.bseinquiry.gov.uk/files/sc/seac24/tab03.pdf





EXPERIMENTAL TRANSMISSION OF BSE TO SHEEP

http://collections.europarchive.org/tna/20090114023211/http://www.bseinquiry.gov.uk/files/sc/seac25/tab05.pdf





SHEEP AND BSE

PERSONAL AND CONFIDENTIAL

SHEEP AND BSE

A. The experimental transmission of BSE to sheep.

Studies have shown that the ''negative'' line NPU flock of Cheviots can be experimentally infected with BSE by intracerebral (ic) or oral challenge (the latter being equivalent to 0.5 gram of a pool of four cow brains from animals confirmed to have BSE).

http://collections.europarchive.org/tna/20090506010048/http://www.bseinquiry.gov.uk/files/sc/seac33/tab02.pdf





RB264

BSE - TRANSMISSION STUDIES

http://collections.europarchive.org/tna/20090113230127/http://www.bseinquiry.gov.uk/files/sc/Seac06/tab06.pdf





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





12/10/76 AGRICULTURAL RESEARCH COUNCIL REPORT OF THE ADVISORY COMMITTE ON SCRAPIE Office Note CHAIRMAN: PROFESSOR PETER WILDY

snip...

A The Present Position with respect to Scrapie A] The Problem Scrapie is a natural disease of sheep and goats. It is a slow and inexorably progressive degenerative disorder of the nervous system and it ia fatal. It is enzootic in the United Kingdom but not in all countries. The field problem has been reviewed by a MAFF working group (ARC 35/77). It is difficult to assess the incidence in Britain for a variety of reasons but the disease causes serious financial loss; it is estimated that it cost Swaledale breeders alone $l.7 M during the five years 1971-1975. A further inestimable loss arises from the closure of certain export markets, in particular those of the United States, to British sheep. It is clear that scrapie in sheep is important commercially and for that reason alone effective measures to control it should be devised as quickly as possible. 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

http://web.archive.org/web/20010305223125/www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf





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).

http://www.nature.com/nature/journal/v236/n5341/abs/236073a0.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





Suspect symptoms

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

28 Mar 01

Like lambs to the slaughter 31 March 2001 by Debora MacKenzie Magazine issue 2284. Subscribe and get 4 free issues. 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.

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.

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.

"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." 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.

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.

http://www.newscientist.com/article/mg16922840.300-like-lambs-to-the-slaughter.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





Tuesday, April 28, 2009

Nor98-like Scrapie in the United States of America

http://nor-98.blogspot.com/2009/04/nor98-like-scrapie-in-united-states-of.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





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





BSE: TIME TO TAKE H.B. PARRY SERIOUSLY

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





Friday, February 04, 2011

NMLB and USDA allow scrapie prion infected mutton to enter food chain on the Navajo Reservation in New Mexico

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

From: Terry S. Singeltary Sr.

To: President.BenShelly

Cc: sroanhorse ; opvp.nelson ; alaughing; georgehardeen; pressoffice

Sent: Thursday, February 03, 2011 12:15 PM

Subject: NMLB and USDA allow scrapie prion infected mutton to enter food chain on the Navajo Reservation in New Mexico

Greetings Honorable People of the Great Navajo Nation, and the Honorable President Ben Shelly,

I send this to you with great concern. ...

http://scrapie-usa.blogspot.com/2011/02/nmlb-and-usda-allow-scrapie-prion.html





Tuesday, November 02, 2010

BSE - ATYPICAL LESION DISTRIBUTION (RBSE 92-21367) statutory (obex only) diagnostic criteria CVL 1992

http://bse-atypical.blogspot.com/2010/11/bse-atypical-lesion-distribution-rbse.html





The statistical incidence of CJD cases in the United States has been revised to reflect that there is one case per 9000 in adults age 55 and older. Eighty-five percent of the cases are sporadic, meaning there is no known cause at present.

http://www.cjdfoundation.org/fact.html



USA WRITTEN CJD QUESTIONNAIRE ???

http://cjdquestionnaire.blogspot.com/





Saturday, March 5, 2011

MAD COW ATYPICAL CJD PRION TSE CASES WITH CLASSIFICATIONS PENDING ON THE RISE IN NORTH AMERICA

http://transmissiblespongiformencephalopathy.blogspot.com/2011/03/mad-cow-atypical-cjd-prion-tse-cases.html





PUTTING THE CART BEFORE THE HORSE, in terms of human health risk $$$

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




Saturday, December 18, 2010

OIE Global Conference on Wildlife Animal Health and Biodiversity - Preparing for the Future (TSE AND PRIONS) Paris (France), 23-25 February 2011

snip...

Greetings,

Thank for your support to the OIE objectives for a safe world. <<<

NOT !

I see again that the OIE has done little to help eradicate all animal TSE from the globe, and in fact in my opinion, have help enhance the spread of BSE and other animal TSE globally by their industry friendly regulations. I tried to warn the OIE in 2002 about CWD and the potential, but very real threat of CWD to humans. I was told that they were seriously considering this. what happened ? NOW, the OIE and the USDA collaborate to make legal the trading of all strains of atypical BSE legal, and in fact have done so with the atypical scrapie, when science has made perfectly clear the risk factors to humans and other species. I have said it once (see below), and i will say again ;

"THE OIE has now shown they are nothing more than a National Trading Brokerage for all strains of animal TSE. AS i said before, OIE should hang up there jock strap now, since it appears they will buckle every time a country makes some political hay about trade protocol, commodities and futures. IF they are not going to be science based, they should do everyone a favor and dissolve there organization."

NOW, some history on the failed OIE BSE/TSE policy, and why the OIE allowed BSE and other TSE to spread around the globe $$$

snip...

http://transmissiblespongiformencephalopathy.blogspot.com/2010/12/oie-global-conference-on-wildlife.html






Sunday, March 27, 2011

SCRAPIE USA UPDATE FEBRUARY 2011

http://transmissiblespongiformencephalopathy.blogspot.com/2011/03/scrapie-usa-update-february-2011.html







TSS

Monday, March 21, 2011

Sheep and Goat BSE Propagate More Efficiently than Cattle BSE in Human PrP Transgenic Mice

Sheep and Goat BSE Propagate More Efficiently than Cattle BSE in Human PrP Transgenic Mice


Danielle Padilla1#, Vincent Béringue2#, Juan Carlos Espinosa1, Olivier Andreoletti3, Emilie Jaumain2, Fabienne Reine2, Laetitia Herzog2, Alfonso Gutierrez-Adan4, Belen Pintado4, Hubert Laude2, Juan Maria Torres1*

1 Centro de Investigación en Sanidad Animal (CISA-INIA), Madrid, Spain, 2 INRA, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France, 3 UMR INRA-ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France, 4 Departamento de Reproducción Animal-INIA, Madrid, Spain

Abstract Top A new variant of Creutzfeldt Jacob Disease (vCJD) was identified in humans and linked to the consumption of Bovine Spongiform Encephalopathy (BSE)-infected meat products. Recycling of ruminant tissue in meat and bone meal (MBM) has been proposed as origin of the BSE epidemic. During this epidemic, sheep and goats have been exposed to BSE-contaminated MBM. It is well known that sheep can be experimentally infected with BSE and two field BSE-like cases have been reported in goats. In this work we evaluated the human susceptibility to small ruminants-passaged BSE prions by inoculating two different transgenic mouse lines expressing the methionine (Met) allele of human PrP at codon 129 (tg650 and tg340) with several sheep and goat BSE isolates and compared their transmission characteristics with those of cattle BSE. While the molecular and neuropathological transmission features were undistinguishable and similar to those obtained after transmission of vCJD in both transgenic mouse lines, sheep and goat BSE isolates showed higher transmission efficiency on serial passaging compared to cattle BSE. We found that this higher transmission efficiency was strongly influenced by the ovine PrP sequence, rather than by other host species-specific factors. Although extrapolation of results from prion transmission studies by using transgenic mice has to be done very carefully, especially when human susceptibility to prions is analyzed, our results clearly indicate that Met129 homozygous individuals might be susceptible to a sheep or goat BSE agent at a higher degree than to cattle BSE, and that these agents might transmit with molecular and neuropathological properties indistinguishable from those of vCJD. Our results suggest that the possibility of a small ruminant BSE prion as vCJD causal agent could not be ruled out, and that the risk for humans of a potential goat and/or sheep BSE agent should not be underestimated.

Author Summary Top Prion diseases, also referred as transmissible spongiform encephalopathies, are fatal neurodegenerative diseases caused by proteinaceous infectious particles denominated “prions.” Prion diseases acquired their first real public relevance with the outbreak of bovine spongiform encephalopathy (BSE) (“mad cow disease”) in the United Kingdom in the 80s and its link with the appearance of a new, variant form of Creutzfeldt-Jakob disease in humans. Recycling of ruminant tissues in meat and bone meal has been proposed as origin of the BSE epidemic. During this episode, sheep and goats have also been exposed to BSE-contaminated meal, so transmission to this species may have occurred. We analyzed the human susceptibility to sheep and goat passaged-BSE prions by using transgenic mice expressing human prion protein (PrP). When different sheep and goat BSE isolates were inoculated in these transgenic mice, higher susceptibility than that observed for cattle BSE was detected and the disease manifestation was similar to that observed in mice inoculated with the new variant of Creutzfeldt-Jakob disease. Our findings suggest that humans are at least equally, and might be even more, susceptible to a sheep or goat BSE agent compared to a cattle BSE one.

snip...

Discussion Top In this study, we compared the transmission features of cattle and sheep/goat BSE prions in two different models of transgenic mice expressing Met129 human PrP (tg650 and tg340 lines) in two different laboratories. In general, the transmission results obtained in both human-PrP transgenic mouse lines were very comparable. Some shortening in survival times was observed in tg650 mice (compared to the tg340 mice line), which was probably due to higher PrP expression levels in this line. Worryingly, our results support the view that an intermediate passage of BSE agent in small ruminants accelerates the appearance of a vCJD-like disease in human PrP mice or markedly increases its transmission efficiency. Because the apparent phenotype of cattle and sheep/goat BSE prions is conserved, these data also unravel an important role of PrPSc primary sequence in the cross-species transmission capacities of prion strains.

The transmission efficiency of cattle BSE isolates in both human-PrP transgenic mouse models was apparently low. With all BSE isolates, whose high infectivity has been demonstrated in bovine-PrP transgenic mice (Tables 2 and 3), very low attack rates were obtained on primary transmission to both tg650 and tg340 mice. Three passages were necessary to achieve a degree of fitness comparable to vCJD in the same mouse line. This low BSE transmission efficiency to human PrP transgenic mice -occasionally accompanied by a strain shift- has also been described by others [40], [41], [42], and suggests a strong although not absolute transmission barrier. Although the exact characteristics and further evolution of the vCJD epidemic still entail uncertainties owing to prolonged incubation times, this apparent high transmission barrier of humans to cattle BSE might be an explanation for the currently low vCJD incidence, considering the high exposure to BSE during the “mad cow” crisis.

Remarkably, a different picture emerged when the sheep and goat BSE isolates were inoculated to human PrP transgenic mouse models. Attack rates approaching 100% were observed from the primary passage onwards and mean incubation times were more consistent with those measured after transmission of vCJD. On further passaging, the neuropathological phenotype and PrPSc type of cattle and sheep/goat BSE agents appeared indistinguishable from the vCJD agent propagated in these mice, as previously demonstrated in bovine transgenic mice [29], thus strongly supporting the view that the same BSE prion strain has been propagated whatever the infecting species. Hence, these observations reproduced in two distinct human transgenic lines with different genetic background and PrP expression levels support the view that transmission efficiency of BSE prions is increased by an intermediate passage in sheep or goat. Although the electrophoretic pattern of sheep/goat and cattle BSE PrPres appeared similar in human-PrP transgenic mice, other assays are currently performed to further compare the biochemical or biophysical properties of the respective proteins are ongoing.

Importantly, the higher attack rates obtained after sheep and goat BSE transmissions compared to cattle BSE are not in accordance with the initial PrPres content of these isolates. In addition, the data from inoculation to BoPrP-Tg reporter mice suggest that cattle BSE and sheep and goat-BSE isolates could have similar transmission efficiency (Table 1 and 2) in the absence of apparent transmission barrier [36]. Furthermore, when the human PrP transgenic lines were inoculated with the BSE agent passaged into bovine and ovine transgenic mice, the transmission results were comparable to those of the cattle and sheep BSE isolates (Figure 7), further supporting the crucial role of the PrPSc primary sequence in the increase of transmission efficiency. Taken together all these considerations suggest that the higher transmission efficiency of sheep and goat BSE isolates in comparison to cattle BSE isolates cannot be linked to a higher infectious titer of the inoculum but must be the outcome of a modification in the pathogenicity of the agent.

Commonly, transmission barriers are determined considering attack rates and quantified by measuring the fall in the mean survival times between the first and second passage. Hence, if we consider PrPres detection as an indicator of successful transmission, our results imply that humans could be significantly more susceptible to a sheep or goat BSE agent than to a cattle BSE agent. On the other hand our results suggest that cattle BSE infection could produce very long latency in humans, with conversion efficiency far below the threshold of detectable PrPres, which is also very worrying since it suggests the possibility of silent carriers.

Our observations, made in two different mouse genetic backgrounds, suggest that the different transmission properties acquired by BSE after passage into either sheep or transgenic mice expressing ovine PrP are strongly related to the ovine PrP primary sequence, rather than to other host species-specific factors. Thus the transmission barrier observed with cattle BSE was fully restored when sheep/goat BSE experienced intermediate passaging into bovine transgenic mice before reinoculation to human PrP mice. In contrast, when the ovine sequence of sheep BSE was maintained, through passage into ARQ ovine PrP transgenic mice, the efficient transmission to human PrP mice was maintained. Apparently, an ovine/caprine PrPSc sequence appears to facilitate human PrP conversion by the BSE agent, compared to a bovine one.

The PrP primary sequence influence seems to depend strongly on the strain involved, since no PrPres was found in either first or second passages of sheep scrapie in tg340 mice (unpublished observations), suggesting no infection, in accordance with the lack of epidemiological evidence linking scrapie with human TSE. Moreover, the low transmission efficiency observed for the cattle BSE agent is not exclusively linked to the bovine PrP sequence since other uncommon BSE strains (BSE-L) are efficiently transmitted to human-PrP mice [41], [43]. Considering the conformational selection model [20], our results would suggest that M129 human PrPC prefers a BSE PrPSc with conformational characteristics templated by the ovine sequence, to a bovine BSE PrPSc. Because a similar increased transmission efficiency of sheep/goat BSE has been reported in wild type mice [44] and transgenic mice expressing elk [45], bovine [29] and porcine [30] PrP, the better structural compatibility conferred by sheep/goat primary PrPSc sequence may not be limited to human PrPC. One explanation might be an alteration in the quaternary structure (after passage into sheep/goat) generating PrPSc polymers less degraded or more rapidly/easily amplified favouring or enhancing the initial conversion. This question is currently being addressed by sedimentation velocity [46] and PMCA experiments. Another possibility, within the quasispecies concept [20], [47], might be that BSE prions confrontation with the sheep and goat primary PrP sequence increases the variety of BSE substrain components, with the following emergence of a markedly adapted component in response to the selection pressure imposed by the interspecies transmission events. On the other hand, this component would not be distinguishable from bovine-passaged BSE prions due to the current limits of the standard biological methods and/or the molecular tools employed here to characterize prion strains. Whatever the mechanism, the notion that a passage through an intermediate species can profoundly alter prion virulence for the human species has important public-health issues, regarding emerging and/or expanding TSEs, like atypical scrapie or CWD.

Although extrapolation of results from prion transmission studies by using transgenic mice has to be done very carefully, especially when human susceptibility to prions is analyzed, our results clearly indicate that Met129 homozygous individuals might be susceptible to a sheep or goat BSE agent at a higher degree than to cattle BSE, and that these agents might transmit with molecular and neuropathological properties indistinguishable from those of vCJD. Although no vCJD cases have been described in Val129 homozygous individuals so far it is relevant to analyze if similar results will be observed in this genotype. This issue is currently being addressed in transmission experiments using transgenic mice expressing Val129 human PrP.

Taken all together, our results suggest that the possibility of a small ruminant BSE prion as vCJD causal agent could not be ruled out, which has important implications on public and animal health policies. On one hand, although the exact magnitude and characteristic of the vCJD epidemic is still unclear, its link with cattle BSE is supported by strong epidemiological ground and several experimental data. On the other hand, the molecular typing performed in our studies, indicates that the biochemical characteristics of the PrPres detected in brains of our sheep and goat BSE-inoculated mice seem to be indistinguishable from that observed in vCJD. Considering the similarity in clinical manifestation of BSE- and scrapie-affected sheep [48], a masker effect of scrapie over BSE, as well as a potential adaptation of the BSE agent through subsequent passages, could not be ruled out. As BSE infected sheep PrPSc have been detected in many peripheral organs, small ruminant-passaged BSE prions might be a more widespread source of BSE infectivity compared to cattle [19], [49], [50]. This fact is even more worrying since our transmission studies suggest that apparently Met129 human PrP favours a BSE agent with ovine rather than a bovine sequence. Finally, it is evident that, although few natural cases have been described and so far we cannot draw any definitive conclusion about the origin of vCJD, we can not underestimate the risk of a potential goat and/or sheep BSE agent.

Citation: Padilla D, Béringue V, Espinosa JC, Andreoletti O, Jaumain E, et al. (2011) Sheep and Goat BSE Propagate More Efficiently than Cattle BSE in Human PrP Transgenic Mice. PLoS Pathog 7(3): e1001319. doi:10.1371/journal.ppat.1001319

Editor: Umberto Agrimi, Istituto Superiore di Sanità, Italy

Received: August 24, 2010; Accepted: February 15, 2011; Published: March 17, 2011

Copyright: © 2011 Padilla et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: This work was supported by grants from European Union (CT-2001-01309, CT2004-023183 and CT2005-036353), Spanish Ministerio de Ciencia e Inovacion (RTA2006-00091) and from UK Food Standards Agency (M03043). D.P. was supported by a fellowship from the Alßan Program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

* E-mail: jmtorres@inia.es

# These authors contributed equally to this work.


http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1001319



AGAIN, MANY THANKS to PLOS for the free full text open access !

MANY THANKS to the Authors of this Study.

NOW, let's look at past history on this important human health topic ;


Friday, February 11, 2011

Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues

http://nor-98.blogspot.com/2011/02/atypicalnor98-scrapie-infectivity-in.html


Sunday, December 12, 2010

EFSA reviews BSE/TSE infectivity in small ruminant tissues News Story 2 December 2010

http://transmissiblespongiformencephalopathy.blogspot.com/2010/12/efsa-reviews-bsetse-infectivity-in.html


Thursday, December 23, 2010

Molecular Typing of Protease-Resistant Prion Protein in Transmissible Spongiform Encephalopathies of Small Ruminants, France, 2002-2009 Volume 17, Number 1 January 2011

http://transmissiblespongiformencephalopathy.blogspot.com/2010/12/molecular-typing-of-protease-resistant.html


Thursday, November 18, 2010

Increased susceptibility of human-PrP transgenic mice to bovine spongiform encephalopathy following passage in sheep

http://bse-atypical.blogspot.com/2010/11/increased-susceptibility-of-human-prp.html


Monday, November 22, 2010

SHEEP WITH MASTITIS TRANSMIT INFECTIOUS PRIONS THROUGH THE MILK

http://scrapie-usa.blogspot.com/2010/11/sheep-with-mastitis-transmit-infectious.html


Published online ahead of print on 26 January 2011 as doi:10.1099/vir.0.028886-0 J Gen Virol (2011), DOI 10.1099/vir.0.028886-0 © 2011 Society for General Microbiology This Article

Emergence of multiple prion strains from single isolates of ovine scrapie

Alana M. Thackray1, Lee Hopkins1, Richard Lockey2, John Spiropoulos2 and Raymond Bujdoso1,3

1 University of Cambridge; 2 VLA, Weybridge

3 E-mail: rb202@cam.ac.uk

The infectious agent associated with prion diseases such as ovine scrapie shows strain diversity. Ovine prion strains have typically been identified by their transmission properties in wild type mice. However, strain typing ovine scrapie isolates in wild type mice may not reveal properties of the infectious prion agent as they exist in the original host. This could be circumvented if ovine scrapie isolates are passaged in ovine PrP transgenic mice. Here we have used incubation time, lesion profile, PrPSc immunohistochemistry and molecular profile to compare the range of ovine prion strains that emerge from sheep scrapie isolates following serial passage in wild type and ovine PrP transgenic mice. We have found that a diverse range of ovine prion strains emerged from homozygous ARQ and VRQ scrapie isolates passaged in wild type and ovine PrP transgenic mice. However, strain-specific PrPSc deposition and PrP27-30 molecular profile patterns were identified in ovine PrP transgenic mice that were not detected in wild type mice. Significantly, we have established that the individual mouse brain selected for transmission during prion strain typing has a significant influence on strain definition. Serial passage of short and long incubation time animals from the same group of scrapie inoculated mice revealed different prion strain phenotypes. Our observations are consistent with the possibility that some scrapie isolates contained more than one prion strain.

Received 10 November 2010; accepted 24 January 2011.

http://vir.sgmjournals.org/cgi/content/abstract/vir.0.028886-0v1


Wednesday, January 19, 2011

EFSA and ECDC review scientific evidence on possible links between TSEs in animals and humans Webnachricht 19 Januar 2011

http://transmissiblespongiformencephalopathy.blogspot.com/2011/01/efsa-and-ecdc-review-scientific.html


Saturday, December 18, 2010

OIE Global Conference on Wildlife Animal Health and Biodiversity – Preparing for the Future (TSE AND PRIONS) Paris (France), 23-25 February 2011

SNIP...

please see full text ;

http://transmissiblespongiformencephalopathy.blogspot.com/2010/12/oie-global-conference-on-wildlife.html


Tuesday, April 28, 2009

Nor98-like Scrapie in the United States of America

http://nor-98.blogspot.com/2009/04/nor98-like-scrapie-in-united-states-of.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


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


Tuesday, April 28, 2009

Nor98-like Scrapie in the United States of America

http://nor-98.blogspot.com/2009/04/nor98-like-scrapie-in-united-states-of.html


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


Scrapie USA

http://scrapie-usa.blogspot.com/


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


Sunday, October 3, 2010

Scrapie, Nor-98 atypical Scrapie, and BSE in sheep and goats North America, who's looking ?

http://nor-98.blogspot.com/2010/10/scrapie-nor-98-atypical-scrapie-and-bse.html


http://nor-98.blogspot.com/


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


Wednesday, February 16, 2011

IN CONFIDENCE SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE

http://scrapie-usa.blogspot.com/2011/02/in-confidence-scrapie-transmission-to.html


Friday, February 04, 2011

NMLB and USDA allow scrapie prion infected mutton to enter food chain on the Navajo Reservation in New Mexico

http://scrapie-usa.blogspot.com/2011/02/nmlb-and-usda-allow-scrapie-prion.html


Tuesday, February 01, 2011

Sparse PrP-Sc accumulation in the placentas of goats with naturally acquired scrapie

Research article

snip...


Conclusions In this study, PrPSc was detected in some but not all placentomes from naturally infected goats using a sensitive western blot assay. PrPSc detectable by IHC was sparsely distributed in caprine cotyledons and ELISA values were lower than observed with most ovine cotyledons. In spite of the poorly defined effects of PRNP genetics, scrapie strain, dose, route and source of infection, the caprine placenta may represent a source of infection to progeny and herd mates as well as a source of persistent environmental contamination. Caprine scrapie is rarely reported in the US and additional studies using experimentally infected goats may be useful in determining the role of the placenta in transmission of caprine scrapie.

http://www.biomedcentral.com/1746-6148/7/7/abstract


http://www.biomedcentral.com/content/pdf/1746-6148-7-7.pdf



" In spite of the poorly defined effects of PRNP genetics, scrapie strain, dose, route and source of infection, the caprine placenta may represent a source of infection to progeny and herd mates as well as a source of persistent environmental contamination. "


Could this route of infection be the cause of the many cases of Goat scrapie from the same herd in Michigan USA ?

Has this been investigated ?

(Figure 6) including five goat cases in FY 2008 that originated from the same herd in Michigan. This is highly unusual for goats, and I strenuously urge that there should be an independent investigation into finding the common denominator for these 5 goats in the same herd in Michigan with Scrapie. ...

Kind Regards, Terry


Scrapie Nor-98 like case in California FY 2011 AS of December 31, 2010.

Scrapie cases in goats FY 2002 - 2011 AS of December 31, 2010 Total goat cases = 21 Scrapie cases, 0 Nor-98 like Scrapie cases (21 field cases, 0 RSSS cases)

Last herd with infected goats disignated in FY 2008 Michigan 8 cases

http://www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/monthly_scrapie_rpt.pps


UPDATED RESPONSE ON MY CONCERNS OF GOAT SCRAPIE IN MICHIGAN ;


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

From: "BioMed Central Comments"

To:

Sent: Wednesday, February 16, 2011 4:13 AM

Subject: Your comment on BMC Veterinary Research 2011, 7:7

Your discussion posting "Scrapie cases Goats from same herd USA Michigan" has been rejected by the moderator as not being appropriate for inclusion on the site.

Dear Mr Singeltary,

Thank you for submitting your comment on BMC Veterinary Research article (2011, 7:7). We have read your comment with interest but we feel that only the authors of the article can answer your question about further investigation of the route of infection of the five goats in Michigan. We advise that you contact the authors directly rather than post a comment on the article.

With best wishes,

Maria

Maria Kowalczuk, PhD Deputy Biology Editor BMC-series Journals

BioMed Central 236 Gray's Inn Road London, WC1X 8HB

+44 20 3192 2000 (tel) +44 20 3192 2010 (fax)

W: www.biomedcentral.com E: Maria.Kowalczuk@biomedcentral.com

Any queries about this decision should be sent to comments@biomedcentral.com

Regards

BMC Veterinary Research


=========END...TSS=========


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


In FY 2010, 72 cases of classical Scrapie and 5 cases of Nor-98 like Scrapie were confirmed...

http://www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/yearly_report.ppsx


Scrapie Nor-98 like case in California FY 2011 AS of December 31, 2010.

Scrapie cases in goats FY 2002 - 2011 AS of December 31, 2010 Total goat cases = 21 Scrapie cases, 0 Nor-98 like Scrapie cases (21 field cases, 0 RSSS cases)

Last herd with infected goats disignated in FY 2008 Michigan 8 cases

http://www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/monthly_scrapie_rpt.pps


Thursday, November 18, 2010

Increased susceptibility of human-PrP transgenic mice to bovine spongiform encephalopathy following passage in sheep

http://bse-atypical.blogspot.com/2010/11/increased-susceptibility-of-human-prp.html


snip... see full text ;

http://scrapie-usa.blogspot.com/2011/02/sparse-prp-sc-accumulation-in-placentas.html



2001


Suspect symptoms

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

28 Mar 2001

Like lambs to the slaughter

31 March 2001

by Debora MacKenzie Magazine issue 2284.

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.

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.

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.

"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." 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.

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.

http://www.newscientist.com/article/mg16922840.300-like-lambs-to-the-slaughter.html



Seven main threats for the future linked to prions

The NeuroPrion network has identified seven main threats for the future linked to prions.

First threat

The TSE road map defining the evolution of European policy for protection against prion diseases is based on a certain numbers of hypotheses some of which may turn out to be erroneous. In particular, a form of BSE (called atypical Bovine Spongiform Encephalopathy), recently identified by systematic testing in aged cattle without clinical signs, may be the origin of classical BSE and thus potentially constitute a reservoir, which may be impossible to eradicate if a sporadic origin is confirmed. Also, a link is suspected between atypical BSE and some apparently sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases constitute an unforeseen first threat that could sharply modify the European approach to prion diseases.

Second threat

snip...

http://www.neuroprion.org/en/np-neuroprion.html


14th ICID International Scientific Exchange Brochure -

Final Abstract Number: ISE.114

Session: International Scientific Exchange

Transmissible Spongiform encephalopathy (TSE) animal and human TSE in North America

update October 2009

T. Singeltary

Bacliff, TX, USA

Background:

An update on atypical BSE and other TSE in North America. Please remember, the typical U.K. c-BSE, the atypical l-BSE (BASE), and h-BSE have all been documented in North America, along with the typical scrapie's, and atypical Nor-98 Scrapie, and to date, 2 different strains of CWD, and also TME. All these TSE in different species have been rendered and fed to food producing animals for humans and animals in North America (TSE in cats and dogs ?), and that the trading of these TSEs via animals and products via the USA and Canada has been immense over the years, decades.

Methods:

12 years independent research of available data

Results:

I propose that the current diagnostic criteria for human TSEs only enhances and helps the spreading of human TSE from the continued belief of the UKBSEnvCJD only theory in 2009. With all the science to date refuting it, to continue to validate this old myth, will only spread this TSE agent through a multitude of potential routes and sources i.e. consumption, medical i.e., surgical, blood, dental, endoscopy, optical, nutritional supplements, cosmetics etc.

Conclusion:

I would like to submit a review of past CJD surveillance in the USA, and the urgent need to make all human TSE in the USA a reportable disease, in every state, of every age group, and to make this mandatory immediately without further delay. The ramifications of not doing so will only allow this agent to spread further in the medical, dental, surgical arena's. Restricting the reporting of CJD and or any human TSE is NOT scientific. Iatrogenic CJD knows NO age group, TSE knows no boundaries. I propose as with Aguzzi, Asante, Collinge, Caughey, Deslys, Dormont, Gibbs, Gajdusek, Ironside, Manuelidis, Marsh, et al and many more, that the world of TSE Transmissible Spongiform Encephalopathy is far from an exact science, but there is enough proven science to date that this myth should be put to rest once and for all, and that we move forward with a new classification for human and animal TSE that would properly identify the infected species, the source species, and then the route.

http://ww2.isid.org/Downloads/14th_ICID_ISE_Abstracts.pdf


Saturday, March 19, 2011

PRION DISEASE MAN AND ANIMAL SPREADING NORTH AMERICA, WHILE FEDERAL FUNDING TO BE AXED

REQUEST FOR CONTINUING FUNDING FOR THE NATIONAL PRION DISEASE PATHOLOGY SURVEILLANCE CENTER


http://transmissiblespongiformencephalopathy.blogspot.com/2011/03/prion-disease-man-and-animal-spreading.html





Terry S. Singeltary Sr.
P.O. Box 42
Bacliff, Texas USA 77518