SCRAPIE USA

Transmissible Spongiform Encephalopathy TSE Prion PrP sheep and goats

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Location: BACLIFF, Texas, United States

My mother was murdered by what I call corporate and political homicide i.e. FOR PROFIT! she died from a rare phenotype of CJD i.e. the Heidenhain Variant of Creutzfeldt Jakob Disease i.e. sporadic, simply meaning from unknown route and source. I have simply been trying to validate her death DOD 12/14/97 with the truth. There is a route, and there is a source. There are many here in the USA. WE must make CJD and all human TSE, of all age groups 'reportable' Nationally and Internationally, with a written CJD questionnaire asking real questions pertaining to route and source of this agent. Friendly fire has the potential to play a huge role in the continued transmission of this agent via the medical, dental, and surgical arena. We must not flounder any longer. ...TSS

Thursday, December 08, 2016

USDA APHIS National Scrapie Eradication Program October 2016 Monthly Report Fiscal Year 2017 atypical NOR-98 Scrapie

National Scrapie Eradication Program

October 2016 Monthly Report Fiscal Year 2017

U.S. Department of Agriculture Animal and Plant Health Inspection Service Veterinary Services Surveillance, Response and Preparedness Services                         

Sheep and Goat Health Program

November 15, 2016


Program Summary At the end of FY 2016, the percent of cull black face sheep found positive at slaughter was 0.01 percent (Chart 1). The current value of this measure is 0.01 percent, a 99 percent decrease compared to FY 2003.
At the end of FY 2016, the percent of cull sheep found positive at slaughter and adjusted for face color* was 0.001 percent (Chart 2). As of October 31, 2016, this measure was 0.001 percent.

Two infected and three source flocks were designated in FY 2016 (Chart 3). No classical scrapie infected or source flocks have been designated in FY 2017. One flock was designated as a Nor98-like source flock in October 2016 based on a sample submitted at the end of FY 2016. Epidemiological studies indicate that  Nor98-like scrapie is either not transmissible or poorly transmissible under natural conditions. Further, the World Organization for Animal Health (OIE) has determined that Nor98-like scrapie is distinct from classical scrapie and is not a listed disease of trade concern. Animals in Nor98-like scrapie infected flocks are not removed and are free to move once they have been officially identified. 

Only one positive goat has been found through RSSS since the start of RSSS in 2003. Based on all goats sampled at slaughter, the prevalence of scrapie in U.S. cull goats is 0.003 percent with an upper 95 percent confidence limit of 0.011 percent. Chart 4 shows the percent positive goats at slaughter each FY since FY 2012.

* See slide 4 for an explanation of adjusted weights. Note: The number of animals sampled annually only allows accurate measurement to about 0.01 percent for the overall rate and about 0.03 percent for when face color is broken out separately, so the changes in the prevalence values smaller than 0.01 or 0.03 percent respectively are within the error of the measure.

Introduction - Program Summary

Positive Cases and Infected/Source Flocks

Positive Scrapie Cases*

One Nor98-like scrapie case was reported in October 2016 (sheep was sampled through RSSS at the end of FY 2016). The last classical scrapie case was reported in April 2016.

Since 2002 the total number of positive goat cases is 41 (Figure 1).

Infected and Source Flocks

As of October 31, 2016, there were two designated infected and source flocks (Figure 2). One flock was designated as a Nor98-like source flock in October 2016.

* Samples collected between October 1, 2016 and October 31, 2016 and confirmed by November 15, 2016.w
Surveillance

Regulatory Scrapie Slaughter Surveillance (RSSS)

RSSS started April 1, 2003.  It is a targeted slaughter surveillance program which is designed to identify infected flocks. 

Samples have been collected from 523,018 animals since April 1, 2003. 

There have been 480 NVSL confirmed positive animals* (471 classical cases and 9 Nor98-like cases) since the beginning of RSSS. 

As of October 31, 2016, 2,538 samples have been collected in FY 2017, 2,144 from sheep and 394 from goats.

There was one Nor98-like scrapie case and no classical scrapie cases reported during October 2016. 

The weighted percentage of samples that have tested positive for each face color from FY 2003 through FY 2017 is depicted in Chart 2. In November 2013, administrative units within APHIS Veterinary Services reorganized from 2 Regions to 6 Districts (Figure 3). The distribution of sheep and goat populations by District is depicted in Chart 5a.  The number of animals collected for FY 2017 by District where collected is shown in Chart 5b.   A monthly comparison of RSSS collections by fiscal year is displayed in Chart 6.  Chart 7is a retrospective 6-month rolling average of the percent positive, black-faced sheep sampled at RSSS collection sites.

*   RSSS positives are reported based on collection date and may have been confirmed after October 31, 2016.

** White, black and mottled face color sheep are weighted based on population. White faced sheep have the highest
weight, so when the uncommon white face positive sheep is found it will cause this statistic to increase.

Introduction –Surveillance (Part 1) Introduction – Surveillance (Part 1)

Surveillance

On-Farm Surveillance

Testing sheep and goats on-farm is an essential part of scrapie surveillance. It includes both regulatory testing of scrapie exposed and potentially exposed sheep and goats and testing sheep and goats on farm for routine surveillance.  As of October 31, 2016, 53 sheep and 76 goats have been tested on-farm for FY 2017. The number of animals tested on-farm by month and by species for FY 2017 is shown in Chart 8.

Total Animals Sampled for Scrapie Testing

As of October 31, 2016, 2,667 animals have been sampled for scrapie testing in FY 2017:

• 2,538 RSSS samples and 129 on-farm samples (Chart 9);

• Of which 2,197 were sheep and 470 were goats.

Distribution of sampling by type (RSSS or on-farm) and by species is shown in Chart 10.

Introduction –Surveillance (Part 2)

Surveillance

State Sampling Minimums

snip...


FY 2017 Sheep and Goat State Sampling Minimums and State Collections District 4

Total Sheep Sampled FY 2017* Sheep Sampling Minimum FY 2017 Total Goats Sampled FY 2017* Goat Sampling Minimum FY 2017

Texas 16 597 12 597

snip...

Scrapie Flock Certification Program: Participating Flocks As of October 31, 2016 

0

snip...

Scrapie Infected and Source Flocks Open Statuses - As of October 31, 2016

Texas and Colorado

snip...



re-Texas Scrapie Sheep Goat samples...LOL...sad face :-(pitiful)...tss


April 22, 2016
 
Scrapie Confirmed in a Hartley County Sheep
 
AUSTIN - Texas Animal Health Commission (TAHC) officials have confirmed scrapie in a Hartley County ewe. The ewe was tested by TAHC after the owner reported signs of weight loss and lack of coordination to their local veterinarian. The premises was quarantined and a flock plan for monitoring is being developed by the TAHC and USDA.
 
"The TAHC is working closely with the flock owner, sharing all of the options for disease eradication," said Dr. David Finch, TAHC Region 1 Director. "We are thankful the producer was proactive in identifying a problem and seeking veterinary help immediately."
 
Texas leads the nation in sheep and goat production. Since 2008, there have been no confirmed cases of scrapie in Texas. The last big spike in Texas scrapie cases was in 2006 when nine infected herds were identified and the last herd was released from restrictions in 2013.
 
According to USDA regulations, Texas must conduct adequate scrapie surveillance by collecting a minimum of 598 sheep samples annually. Since USDA slaughter surveillance started in FY 2003, the percent of cull sheep found positive for scrapieat slaughter (once adjusted for face color) has decreased 90 percent.
 
Scrapie is the oldest known transmissible spongiform encephalopathies, and under natural conditions only sheep and goats are known to be affected by scrapie. It is a fatal disease that affects the central nervous system of sheep and goats. It is not completely understood how scrapie is passed from one animal to the next and apparently healthy sheep infected with scrapie can spread the disease. Sheep and goats are typically infected as young lambs or kids, though adult sheep and goats can become infected.
 
The most effective method of scrapie prevention is to maintain a closed flock. Raising replacement ewes, purchasing genetically resistant rams and ewes,or buying from a certified-free scrapie flock are other options to reduce the risk of scrapie. At this time the resistant genetic markers in goats have not been identified, therefore it is important to maintain your sheep and goat herds separately.
 
The incubation period for Scrapie is typically two to five years. Producers should record individual identification numbers and the seller's premise identification number on purchase and sales records. These records must be maintained for a minimum of five years.
 
Producers should notify the Texas Animal Health Commission (800-550-8242) or the USDA-Austin Office (512-383-2400) if they have an adult sheep or goat with neurologic signs such as incoordination, behavioral changes, or intense itching with wool loss. Producers may order scrapie identification tags by calling 866-873-2824. For more information, please visit our website at:
 
 
###
 
 
Texas Scrapie Confirmed in a Hartley County Sheep where CWD was detected in a Mule Deer, was there a link to the two ???
 
Sunday, May 22, 2016
 
TEXAS CWD DEER BREEDERS PLEA TO GOVERNOR ABBOTT TO CIRCUMVENT TPWD SOUND SCIENCE TO LET DISEASE SPREAD
 
 

Thursday, December 08, 2016

TEXAS TAHC confirmed Chronic Wasting Disease (CWD) in a free-ranging elk Dallam County


Saturday, December 03, 2016

TEXAS CHRONIC WASTING DISEASE CWD TSE PRION UPDATE 35 CASES TO DATE


Wednesday, December 07, 2016

Student Assistant (Temporary) – Chronic Wasting Disease: Texas A&M Veterinary Medical Diagnostic Laboratory


http://chronic-wasting-disease.blogspot.com/2016/12/student-assistant-temporary-chronic.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.
 

 
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
 

 
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.
 

 
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.
 

 
RESEARCH
 
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 17, No. 5, May 2011
 
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
 
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-specifi c 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 fi ndings 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...
 
Although we do not have epidemiologic evidence that supports the effi cient spread of disease in the fi eld, these data imply that disease is potentially transmissible under fi eld 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 fi nding 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 quantifi ed, 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 confi rmatory 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.
 
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 17, No. 5, May 2011
 

 
Monday, April 25, 2011
 
Experimental Oral Transmission of Atypical Scrapie to Sheep
 
Volume 17, Number 5-May 2011
 

 
Friday, February 11, 2011
 
Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues
 

 
Tuesday, April 28, 2009
 
Nor98-like Scrapie in the United States of America
 
 

 
Thursday, March 29, 2012
 
atypical Nor-98 Scrapie has spread from coast to coast in the USA 2012
 
NIAA Annual Conference April 11-14, 2011San Antonio, Texas
 

 
*** Canada 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.
 
 


Monday, May 02, 2016

*** Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo ***

http://chronic-wasting-disease.blogspot.com/2016/05/zoonotic-potential-of-cwd-prions-update.html


 Saturday, April 23, 2016

PRION 2016 TOKYO

Saturday, April 23, 2016

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

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

Taylor & Francis

Prion 2016 Animal Prion Disease Workshop Abstracts

WS-01: Prion diseases in animals and zoonotic potential

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

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

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

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

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

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

 Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with ef?ciency comparable to that of cattle BSE. While the ef?ciency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20


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

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

 snip...

 R. BRADLEY

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


                             

Location: Virus and Prion Research

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


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

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

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

 http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160


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

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

 Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.

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

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

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

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

 ===============

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

 ***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.
 
https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf


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

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

http://scrapie-usa.blogspot.com/2016/04/scrapie-ws-01-prion-diseases-in-animals.html


*** WDA 2016 NEW YORK ***

 We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions.

 Student Presentations Session 2

 The species barriers and public health threat of CWD and BSE prions

 Ms. Kristen Davenport1, Dr. Davin Henderson1, Dr. Candace Mathiason1, Dr. Edward Hoover1 1Colorado State University

 Chronic wasting disease (CWD) is spreading rapidly through cervid populations in the USA. Bovine spongiform encephalopathy (BSE, mad cow disease) arose in the 1980s because cattle were fed recycled animal protein. These and other prion diseases are caused by abnormal folding of the normal prion protein (PrP) into a disease causing form (PrPd), which is pathogenic to nervous system cells and can cause subsequent PrP to misfold. CWD spreads among cervids very efficiently, but it has not yet infected humans. On the other hand, BSE was spread only when cattle consumed infected bovine or ovine tissue, but did infect humans and other species. The objective of this research is to understand the role of PrP structure in cross-species infection by CWD and BSE. To study the propensity of each species’ PrP to be induced to misfold by the presence of PrPd from verious species, we have used an in vitro system that permits detection of PrPd in real-time. We measured the conversion efficiency of various combinations of PrPd seeds and PrP substrate combinations. We observed the cross-species behavior of CWD and BSE, in addition to feline-adapted CWD and BSE. We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions. CWD is unique among prion diseases in its rapid spread in natural populations. BSE prions are essentially unaltered upon passage to a new species, while CWD adapts to the new species. This adaptation has consequences for surveillance of humans exposed to CWD.

Wildlife Disease Risk Communication Research Contributes to Wildlife Trust Administration Exploring perceptions about chronic wasting disease risks among wildlife and agriculture professionals and stakeholders

http://www.wda2016.org/uploads/5/8/6/1/58613359/wda_2016_conference_proceedings_low_res.pdf


PRION 2016 TOKYO

Zoonotic Potential of CWD Prions: An Update

Ignazio Cali1, Liuting Qing1, Jue Yuan1, Shenghai Huang2, Diane Kofskey1,3, Nicholas Maurer1, Debbie McKenzie4, Jiri Safar1,3,5, Wenquan Zou1,3,5,6, Pierluigi Gambetti1, Qingzhong Kong1,5,6 1Department of Pathology, 3National Prion Disease Pathology Surveillance Center, 5Department of Neurology, 6National Center for Regenerative Medicine, Case Western Reserve University, Cleveland, OH 44106, USA. 4Department of Biological Sciences and Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, 2Encore Health Resources, 1331 Lamar St, Houston, TX 77010

Chronic wasting disease (CWD) is a widespread and highly transmissible prion disease in free-ranging and captive cervid species in North America. The zoonotic potential of CWD prions is a serious public health concern, but the susceptibility of human CNS and peripheral organs to CWD prions remains largely unresolved. We reported earlier that peripheral and CNS infections were detected in transgenic mice expressing human PrP129M or PrP129V. Here we will present an update on this project, including evidence for strain dependence and influence of cervid PrP polymorphisms on CWD zoonosis as well as the characteristics of experimental human CWD prions.

PRION 2016 TOKYO In Conjunction with Asia Pacific Prion Symposium 2016 PRION 2016 Tokyo Prion 2016

http://prion2016.org/dl/newsletter_03.pdf


Cervid to human prion transmission

Kong, Qingzhong

Case Western Reserve University, Cleveland, OH, United States

Abstract

Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans. We hypothesize that:

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

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

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

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

Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of "humanized" Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental "human CWD" samples will also be generated for Aim 3.

Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1.

Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental "human CWD" samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions.

Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.

Public Health Relevance There are significant and increasing human exposure to cervid prions because chronic wasting disease (CWD, a widespread and highly infectious prion disease among deer and elk in North America) continues spreading and consumption of venison remains popular, but our understanding on cervid-to-human prion transmission is still very limited, raising public health concerns. This proposal aims to define the zoonotic risks of cervid prions and set up and apply essays to detect CWD zoonosis using mouse models and in vitro methods. The findings will greatly expand our knowledge on the potentials and characteristics of cervid prion transmission in humans, establish reliable essays for such infections and may discover the first case(s) of CWD infection in humans.

Funding Agency Agency National Institute of Health (NIH)

Institute National Institute of Neurological Disorders and Stroke (NINDS)

Type Research Project (R01)

Project # 1R01NS088604-01A1

Application # 9037884

Study Section Cellular and Molecular Biology of Neurodegeneration Study Section (CMND)

Program Officer Wong, May

Project Start 2015-09-30

Project End 2019-07-31

Budget Start 2015-09-30

Budget End 2016-07-31

Support Year 1

Fiscal Year 2015

Total Cost $337,507

Indirect Cost $118,756

Institution

Name Case Western Reserve University

Department Pathology

Type Schools of Medicine

DUNS # 077758407

City Cleveland

State OH

Country United States

Zip Code 44106

http://grantome.com/grant/NIH/R01-NS088604-01A1


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

We hypothesize that:

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

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

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

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

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

Key Molecular Mechanisms of TSEs

Zabel, Mark D.

Colorado State University-Fort Collins, Fort Collins, CO, United States Abstract Prion diseases, or transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative diseases affecting humans, cervids, bovids, and ovids. The absolute requirement of PrPC expression to generate prion diseases and the lack of instructional nucleic acid define prions as unique infectious agents. Prions exhibit species-specific tropism, inferring that unique prion strains exist that preferentially infct certain host species and confront transmission barriers to heterologous host species. However, transmission barriers are not absolute. Scientific consensus agrees that the sheep TSE scrapie probably breached the transmission barrier to cattle causing bovine spongiform encephalopathy that subsequently breached the human transmission barrier and likely caused several hundred deaths by a new-variant form of the human TSE Creutzfeldt-Jakob disease in the UK and Europe. The impact to human health, emotion and economies can still be felt in areas like farming, blood and organ donations and the threat of a latent TSE epidemic. This precedent raises the real possibility of other TSEs, like chronic wasting disease of cervids, overcoming similar human transmission barriers. A groundbreaking discovery made last year revealed that mice infected with heterologous prion strains facing significant transmission barriers replicated prions far more readily in spleens than brains6. Furthermore, these splenic prions exhibited weakened transmission barriers and expanded host ranges compared to neurogenic prions. These data question conventional wisdom of avoiding neural tissue to avoid prion xenotransmission, when more promiscuous prions may lurk in extraneural tissues. Data derived from work previously funded by NIH demonstrate that Complement receptors CD21/35 bind prions and high density PrPC and differentially impact prion disease depending on the prion isolate or strain used. Recent advances in live animal and whole organ imaging have led us to generate preliminary data to support novel, innovative approaches to assessing prion capture and transport. We plan to test our unifying hypothesis for this proposal that CD21/35 control the processes of peripheral prion capture, transport, strain selection and xenotransmission in the following specific aims. 1. Assess the role of CD21/35 in splenic prion strain selection and host range expansion. 2. Determine whether CD21/35 and C1q differentially bind distinct prion strains 3. Monitor the effects of CD21/35 on prion trafficking in real time and space 4. Assess the role of CD21/35 in incunabular prion trafficking

Public Health Relevance Transmissible spongiform encephalopathies, or prion diseases, are devastating illnesses that greatly impact public health, agriculture and wildlife in North America and around the world. The impact to human health, emotion and economies can still be felt in areas like farming, blood and organ donations and the threat of a latent TSE epidemic. This precedent raises the real possibility of other TSEs, like chronic wasting disease (CWD) of cervids, overcoming similar human transmission barriers. Early this year Canada reported its first case of BSE in over a decade audits first case of CWD in farmed elk in three years, underscoring the need for continued vigilance and research. Identifying mechanisms of transmission and zoonoses remains an extremely important and intense area of research that will benefit human and other animal populations.

Funding Agency Agency National Institute of Health (NIH)

Institute National Institute of Allergy and Infectious Diseases (NIAID)

Type High Priority, Short Term Project Award (R56)

Project # 1R56AI122273-01A1

Application # 9211114

Study Section Cellular and Molecular Biology of Neurodegeneration Study Section (CMND)

Program Officer Beisel, Christopher E

Project Start 2016-02-16

Project End 2017-01-31

Budget Start 2016-02-16

Budget End 2017-01-31

Support Year 1

Fiscal Year 2016

Total Cost

Indirect Cost Institution Name Colorado State University-Fort Collins

Department Microbiology/Immun/Virology

Type Schools of Veterinary Medicine

DUNS # 785979618 City Fort Collins

State CO

Country United States

Zip Code 80523

http://grantome.com/grant/NIH/R56-AI122273-01A1


PMCA Detection of CWD Infection in Cervid and Non-Cervid Species

Hoover, Edward Arthur

Colorado State University-Fort Collins, Fort Collins, CO, United States

Abstract Chronic wasting disease (CWD) of deer and elk is an emerging highly transmissible prion disease now recognized in 18 States, 2 Canadian provinces, and Korea. We have shown that Infected deer harbor and shed high levels of infectious prions in saliva, blood, urine, and feces, and in the tissues generating those body fluids and excreta, thereby leading to facile transmission by direct contact and environmental contamination. We have also shown that CWD can infect some non-cervid species, thus the potential risk CWD represents to domestic animal species and to humans remains unknown. Whether prions borne in blood, saliva, nasal fluids, milk, or excreta are generated or modified in the proximate peripheral tissue sites, may differ in subtle ways from those generated in brain, or may be adapted for mucosal infection remain open questions. The increasing parallels in the pathogenesis between prion diseases and human neurodegenerative conditions, such as Alzheimer's and Parkinson's diseases, add relevance to CWD as a transmissible protein misfolding disease. The overall goal of this work is to elucidate the process of CWD prion transmission from mucosal secretory and excretory tissue sites by addressing these questions: (a) What are the kinetics and magnitude of CWD prion shedding post-exposure? (b) Are excreted prions biochemically distinct, or not, from those in the CNS? (c) Are peripheral epithelial or CNS tissues, or both, the source of excreted prions? and (d) Are excreted prions adapted for horizontal transmission via natural/trans-mucosal routes? The specific aims of this proposal are: (1) To determine the onset and consistency of CWD prion shedding in deer and cervidized mice; (2); To compare the biochemical and biophysical properties of excretory vs. CNS prions; (3) To determine the capacity of peripheral tissues to support replication of CWD prions; (4) To determine the protease- sensitive infectious fraction of excreted vs. CNS prions; and (5) To compare the mucosal infectivity of excretory vs. CNS prions. Understanding the mechanisms that enable efficient prion dissemination and shedding will help elucidate how horizontally transmissible prions evolve and succeed, and is the basis of this proposal. Understanding how infectious misfolded proteins (prions) are generated, trafficked, shed, and transmitted will aid in preventing, treating, and managing the risks associated with these agents and the diseases they cause.

Public Health Relevance Chronic wasting disease (CWD) of deer and elk is an emergent highly transmissible prion disease now recognized throughout the USA as well as in Canada and Korea. We have shown that infected deer harbor and shed high levels of infectious prions in saliva, blood, urine, and feces thereby leading to transmission by direct contact and environmental contamination. In that our studies have also shown that CWD can infect some non-cervid species, the potential risk CWD may represents to domestic animal species and humans remains unknown. The increasing parallels in the development of major human neurodegenerative conditions, such as Alzheimer's and Parkinson's diseases, and prion diseases add relevance to CWD as a model of a transmissible protein misfolding disease. Understanding how infectious misfolded proteins (prions) are generated and transmitted will aid in interrupting, treating, and managing the risks associated with these agents and the diseases they cause.

Funding Agency Agency National Institute of Health (NIH)

Institute National Institute of Neurological Disorders and Stroke (NINDS)

Type Research Project (R01)

Project # 4R01NS061902-07

Application # 9010980

Study Section Cellular and Molecular Biology of Neurodegeneration Study Section (CMND)

Program Officer Wong, May Project Start 2009-09-30

Project End 2018-02-28

Budget Start 2016-03-01

Budget End 2017-02-28

Support Year 7

Fiscal Year 2016

Total Cost $409,868

Indirect Cost $134,234 Institution Name Colorado State University-Fort Collins

Department Microbiology/Immun/Virology

Type Schools of Veterinary Medicine

DUNS # 785979618 City Fort Collins

State CO

Country United States

Zip Code 80523

http://grantome.com/grant/NIH/R01-NS061902-07


Monday, May 02, 2016

*** Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo ***

http://chronic-wasting-disease.blogspot.com/2016/05/zoonotic-potential-of-cwd-prions-update.html


LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$

*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***

https://www.landesbioscience.com/journals/prion/article/28124/?nocache=112223249
 

*** The potential impact of prion diseases on human health was greatly magnified by the recognition that interspecies transfer of BSE to humans by beef ingestion resulted in vCJD. While changes in animal feed constituents and slaughter practices appear to have curtailed vCJD, there is concern that CWD of free-ranging deer and elk in the U.S. might also cross the species barrier. Thus, consuming venison could be a source of human prion disease. Whether BSE and CWD represent interspecies scrapie transfer or are newly arisen prion diseases is unknown. Therefore, the possibility of transmission of prion disease through other food animals cannot be ruled out. There is evidence that vCJD can be transmitted through blood transfusion. There is likely a pool of unknown size of asymptomatic individuals infected with vCJD, and there may be asymptomatic individuals infected with the CWD equivalent. These circumstances represent a potential threat to blood, blood products, and plasma supplies.

http://cdmrp.army.mil/prevfunded/nprp/NPRP_Summit_Final_Report.pdf
 


Wednesday, November 09, 2016
 
Norway and Finland Rule Changes for importation and exportation of deer to limit the spread of skrantesjuke (CWD)
 
 

Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission



December 2016 CDC Emerging Infectious Disease Journal CWD Horizontal Transmission


Monday, September 05, 2016

Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission Major Findings for Norway



Thursday, September 22, 2016

NORWAY DETECTS 5TH CASE OF CHRONIC WASTING DISEASE CWD TSE PRION Skrantesjuke



SUNDAY, OCTOBER 02, 2016

*** What is the risk of a cervid TSE being introduced from Norway into Great Britain? Qualitative Risk Assessment September 2016



Wednesday, September 7, 2016

*** An assessment of the long-term persistence of prion infectivity in aquatic environments



Friday, September 02, 2016

*** Chronic Wasting Disease Drives Population Decline of White-Tailed Deer



*** Infectious agent of sheep scrapie may persist in the environment for at least 16 years ***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3



Saturday, July 23, 2016

BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION SURVEILLANCE, TESTING, AND SRM REMOVAL UNITED STATE OF AMERICA UPDATE JULY 2016

http://bovineprp.blogspot.com/2016/07/bovine-spongiform-encephalopathy-bse.html

Tuesday, July 26, 2016

Atypical Bovine Spongiform Encephalopathy BSE TSE Prion UPDATE JULY 2016

http://bse-atypical.blogspot.com/2016/07/atypical-bovine-spongiform.html


Diagnosis and Reporting of Creutzfeldt-Jakob Disease

Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

To the Editor: In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.

Terry S. Singeltary, Sr Bacliff, Tex

1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323.

http://jama.jamanetwork.com/article.aspx?articleid=1031186


FDA CJD BSE TSE Prion Scientific Advisors and Consultants Staff January 2001 Meeting Singeltary Submission

2001 FDA CJD TSE Prion Singeltary Submission
 
http://www.fda.gov/ohrms/dockets/ac/01/slides/3681s2_09.pdf
 

Terry S. Singeltary Sr.



 


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