Monday, September 05, 2016

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

Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research

 

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

 

Author

 

item Moore, Sarah item Kunkle, Robert item West greenlee, Mary item Nicholson, Eric item Richt, Juergen item Hamir, Amirali item Waters, Wade item Greenlee, Justin

 

Submitted to: Emerging Infectious Diseases Publication Type: Peer reviewed journal Publication Acceptance Date: 8/29/2016 Publication Date: N/A Citation:

 

Interpretive Summary: Chronic wasting disease (CWD) is a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America and was recently diagnosed in a single free-ranging reindeer (Rangifer tarandus tarandus) in Norway. CWD is a transmissible spongiform encephalopathy (TSE) that is caused by infectious proteins called prions that are resistant to various methods of decontamination and environmental degradation. Little is known about the susceptibility of or potential for transmission amongst reindeer. In this experiment, we tested the susceptibility of reindeer to CWD from various sources (elk, mule deer, or white-tailed deer) after intracranial inoculation and tested the potential for infected reindeer to transmit to non-inoculated animals by co-housing or housing in adjacent pens. Reindeer were susceptible to CWD from elk, mule deer, or white-tailed deer sources after experimental inoculation. Most importantly, non-inoculated reindeer that were co-housed with infected reindeer or housed in pens adjacent to infected reindeer but without the potential for nose-to-nose contact also developed evidence of CWD infection. This is a major new finding that may have a great impact on the recently diagnosed case of CWD in the only remaining free-ranging reindeer population in Europe as our findings imply that horizontal transmission to other reindeer within that herd has already occurred. Further, this information will help regulatory and wildlife officials developing plans to reduce or eliminate CWD and cervid farmers that want to ensure that their herd remains CWD-free, but were previously unsure of the potential for reindeer to transmit CWD.

 

Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal prion disease of cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, and CWD was recently reported in a free-ranging reindeer of Norway. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWDwtd), mule deer (Odocoileus hemionus; CWDmd), or elk (Cervus elaphus nelsoni; CWDelk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWDwtd, CWDmd, or CWDelk. Two years after challenge of inoculated reindeer, non-inoculated negative control reindeer were introduced into the same pen as the CWDwtd inoculated reindeer (direct contact; n=4) or into a pen adjacent to the CWDmd inoculated reindeer (indirect contact; n=2). Experimentally inoculated reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrPcwd). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (months PI). PrPcwd was detected in 5 out of 6 sentinel reindeer although only 2 out of 6 developed clinical disease during the study period (< 57 months PI). We have shown that reindeer are susceptible to CWD from various cervid sources and can transmit CWD to naïve reindeer both directly and indirectly.

 


 

***Most importantly, non-inoculated reindeer that were co-housed with infected reindeer or housed in pens adjacent to infected reindeer but without the potential for nose-to-nose contact also developed evidence of CWD infection.

 

***This is a major new finding that may have a great impact on the recently diagnosed case of CWD in the only remaining free-ranging reindeer population in Europe as our findings imply that horizontal transmission to other reindeer within that herd has already occurred.

 

***We have shown that reindeer are susceptible to CWD from various cervid sources and can transmit CWD to naïve reindeer both directly and indirectly.

 

Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research

 

Title: Transmission of chronic wasting disease to sentinel reindeer (Rangifer tarandus tarandus))

 

Author

 

item Moore, S item Kunkle, Robert item Nicholson, Eric item Richt, Juergen item Hamir, Amirali item Waters, Wade item Greenlee, Justin

 

Submitted to: American College of Veterinary Pathologists Meeting Publication Type: Abstract only Publication Acceptance Date: 8/12/2015 Publication Date: N/A Citation:

 

Interpretive Summary: Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of North American cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, but CWD has not been reported in free-ranging caribou (Rangifer tarandus caribou) or farmed reindeer. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWD-wtd), mule deer (Odocoileus hemionus; CWD-md), or elk (Cervus elaphus nelsoni; CWD-elk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWD-wtd, CWD-md, or CWD-elk. Two years after challenge of inoculated reindeer, non-inoculated control reindeer were introduced into the same pen as the CWD-wtd inoculated reindeer (n=4) or into a pen adjacent to the CWD-md inoculated reindeer (n=2). Reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrP-CWD). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (MPI). PrP-CWD was detected in 5/6 sentinel reindeer although only 2/6 developed clinical disease during the study period (<57 and="" are="" both="" can="" cervid="" cwd="" directly="" div="" from="" have="" indirectly.="" mpi="" naive="" reindeer="" shown="" sources="" susceptible="" that="" to="" transmit="" various="" we="">
 


 

Wednesday, August 31, 2016

 

NORWAY CONFIRMS 4TH CASE OF CHRONIC WASTING DISEASE CWD TSE PRION IN SECOND CARIBOU

 


 

Saturday, September 03, 2016

 

NORWAY Regulation concerning temporary measures to reduce the spread of Chronic Wasting Disease (CWD) as 4th case of skrantesjuke confirmed in Sogn og Fjordane

 


 

TSE PRIONS AKA MAD COW TYPE DISEASE, LIONS AND TIGERS AND BEARS, OH MY!

 

DEER BRAIN SURVEY

 

***5. Although the sample size would be too small to provide scientifically valid evidence that there is no cervine spongiform encephalopathy in the UK (4,000 odd brains would be necessary for that), a negative result would aid our efforts to have trade in deer resumed. ...end...tss

 


 

Subject: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY

 

Date: Thu, 17 Oct 2002 17:04:51 –0700

 

From: "Terry S. Singeltary Sr."

 

Reply-To: Bovine Spongiform Encephalopathy

 

To: BSE-L

 

Greetings BSE-L,

 

is there any other CWD surveys/testing in the UK on their deer? what sort of testing has been done to date on UK/EU deer? any input would be helpful... thank you

 

DEER SPONGIFORM ENCEPHALOPATHY SURVEY

 

CVO BSE 1 28

 

DEER BRAIN SURVEY

 

1. The Parliamentary Secretary will wish to be aware of a survey of deer brains for signs of a spongiform encephalopathy.

 

2. The purpose of the study will be to gather evidence of freedom from any spongiform encephalopathy in the UK deer- population to support our efforts to resume trade in deer with countries with which BSE has disrupted it.

 

3. This will be a low key study with no publicity to avoid unnecessary media interest. It will be carried out in two stages:

 

(i) A small scale examination of around 30 deer brains to establish the normal histology of the healthy brain; and

 

(ii) A larger scale random examination of 300 or more adult deer brains drawn from both deer farms and parks to establish whether there is any evidence of a cervine spongiform encephalopathy.

 

4. The industry have agreed to cooperate with the study and will supply the necessary brain material. No compensation will be paid. The only cost to Government will be for the laboratory examinations which will be borne within existing resources.

 

*** 5. Although the sample size would be too small to provide scientifically valid evidence that there is no cervine spongiform encephalopathy in the UK (4,000 odd brains would be necessary for that), a negative result would aid our efforts to have trade in deer resumed.

 

ROBERT LOWSON

 

Animal Health (Disease Control) Division

 

081 330 8042 - GTN 3836

 

Fax: 081 330 7862

 

Room 28A TOLB

 

20 November 1991

 

Mr Tanner - PS/Mr Maclean

 

c.c. PS/Minister Dr P Dawson Mr Lawrence PS/Permanent Secretary Mr Dugdalé Dr Matthews Mr Capstick Mr Bradley — CVL Mr Maslin Mr MeldrumL Mr Wilesmith - CVL Mr Thomson SOAFD Mr Haddon Mr Bell Mr Shannon DANI Mr X Taylor Mr Robertson Mr Podmore WOAD

 

91/11.20/4.1

 


 

***5. Although the sample size would be too small to provide scientifically valid evidence that there is no cervine spongiform encephalopathy in the UK (4,000 odd brains would be necessary for that), a negative result would aid our efforts to have trade in deer resumed.’’ LMAO...DOES THAT EVER SOUND FAMILIAR...TSS

 

Wednesday, August 31, 2016

 

NORWAY CONFIRMS 4TH CASE OF CHRONIC WASTING DISEASE CWD TSE PRION IN SECOND CARIBOU

 


 

Tuesday, August 02, 2016

 

Chronic wasting disease of deer – is the battle to keep Europe free already lost?

 


 

Tuesday, April 12, 2016

 

The first detection of Chronic Wasting Disease (CWD) in Europe free-ranging reindeer from the Nordfjella population in South-Norway.

 


 

Tuesday, June 14, 2016

 

*** Chronic Wasting Disease (CWD) in a moose from Selbu in Sør-Trøndelag Norway ***

 


 

Thursday, July 07, 2016

 

Norway reports a third case Chronic Wasting Disease CWD TSE Prion in 2nd Norwegian moose

 

14/06/2016 - Norway reports a third case

 


 

Saturday, July 16, 2016

 

Chronic wasting Disease in Deer (CWD or Spongiform Encephalopathy) The British Deer Society 07/04/2016

 

Red Deer Ataxia or Chronic Wasting Disease CWD TSE PRION?

 

could this have been cwd in the UK back in 1970’S ???

 


 


 


 


 

SEE FULL TEXT ;

 


 

Sunday, August 28, 2016

 

CONFIDENTIAL

 

Transmissible Spongiform Encephalopathy TSE Prion and how Politics and Greed by the Industry spread madcow type diseases from species to species and around the globe

 

TSE PRIONS AKA MAD COW TYPE DISEASE, LIONS AND TIGERS AND BEARS, OH MY!

 

Please be assured, the USA does NOT have any clue as to what the real perspective on the TSE prion disease in domestic feline and canine, much less our big wild cats, OR any other species including humans for that matter, but one thing for sure, the studies and history of the mad cow debacle below are deeply concerning with regards, to humans and wild big cats like mountain lions, cougars, lynx, Jaguar, and such, that feed on cervids that are infected with CWD. one thing for sure, don’t kid yourselves, all are very much susceptible to the TSE Prion disease, and if you don’t look, you don’t find, problems solved$$$

 


 

Chronic Wasting Disease CWD TSE Prion Update

 

Subject: Stakeholder Perspectives on Chronic Wasting Disease Risk and Management on the Canadian Prairies

 

research article

 

Stakeholder Perspectives on Chronic Wasting Disease Risk and Management on the Canadian Prairies

 

Kari Amick, Douglas Clark & Ryan K. Brook

 

Page 408-424

 

Published online: 31 Aug 2015

 

Download citation http://dx.doi.org/10.1080/10871209.2015.1046095 Crossmark

 

Abstract

 

Chronic wasting disease (CWD) is an infectious disease caused by a prion that results in neurodegeneration and death in cervids. This study uses Q methodology to characterize stakeholder perspectives about CWD risk and management on the Canadian prairies, and to understand the potential for CWD management using an adaptive governance framework. Workshops and individual interviews were conducted with 16 stakeholders in Saskatchewan and Manitoba. Problem definitions framed CWD as a technical problem calling for technical solutions. All perspectives on solutions focused on the importance of education and the idea that management should fit within a national management strategy. A unique Aboriginal perspective also emerged and warrants further exploration. Results also indicated that although stakeholders wish to be involved with CWD management, they trust and expect government leadership, and are disinterested in adaptive governance. Challenges for stakeholder involvement in Canadian CWD management include a lack of sufficient leadership and general ambivalence.

 

Keywords: adaptive governance, chronic wasting disease, Q methodology, stakeholder perspectives, wildlife disease management,

 


 

Friday, September 02, 2016

 

Canada Chronic Wasting Disease CWD Surveillance Update 2016

 


 

Sunday, August 28, 2016

 

CONFIDENTIAL

 

Transmissible Spongiform Encephalopathy TSE Prion and how Politics and Greed by the Industry spread madcow type diseases from species to species and around the globe

 

TSE PRIONS AKA MAD COW TYPE DISEASE, LIONS AND TIGERS AND BEARS, OH MY!

 


 


 

Sunday, December 14, 2014

 

TEXAS 84th Legislature commencing this January, deer breeders are expected to advocate for bills that will seek to further deregulate their industry

 


 

Texas Intrastate – within state movement of all Cervid or Trucking Chronic Wasting Disease CWD TSE Prion Moratorium

 


 

Monday, July 18, 2016

 

Texas Parks Wildlife Dept TPWD HIDING TSE (CWD) in Deer Herds, Farmers Sampling Own Herds, Rapid Testing, False Negatives, a Recipe for Disaster

 


 

*** TEXAS Thirteen new cases of chronic wasting disease (CWD) were confirmed at a Medina County captive white-tailed deer breeding facility on June 29, 2016***

 


 

*** How Did CWD Get Way Down In Medina County, Texas?

 

DISCUSSION Observations of natural outbreaks of scrapie indicated that the disease spread from flock to flock by the movement of infected, but apparently normal, sheep which were incubating the disease.

 

There was no evidence that the disease spread to adjacent flocks in the absent of such movements or that vectors or other host species were involved in the spread of scrapie to sheep or goats; however, these possibilities should be kept open...

 


 


 


 

Tuesday, August 02, 2016

 

TEXAS TPWD Sets Public Hearings on Deer Movement Rule Proposals in Areas with CWD Rule Terry S. Singeltary Sr. comment submission

 


 

Thursday, August 25, 2016

 

TPWD Action Disease Detection and Response – Chronic Wasting Disease TPW Commission Adopts New CWD Zones, Deer Movement Rules August 25, 2016

 

This map shows the recently imposed Surveillance Zone for CWD in portions of Bandera, Medina and Uvalde counties.

 


 


 

Arkansas Chronic Wasting Disease CWD TSE Prion Potentially Trucked in from Missouri, what about Florida and ?

 


 

Wednesday, July 27, 2016

 

Arkansas CWD 101 positive cases documented to date, Biologists to take additional samples in in southern Pope County, Aug. 1-5

 


 

Tuesday, August 30, 2016

 

NEBRASKA CHRONIC WASTING DISEASE CWD TSE PRION UPDATE REPORT

 


 

Monday, August 29, 2016

 

*** NWHC USGS CHRONIC WASTING DISEASE CWD TSE PRION UPDATE ***

 


 

Friday, September 02, 2016

 

Chronic Wasting Disease Drives Population Decline of White-Tailed Deer

 


 

Sunday, September 04, 2016

 

Stakeholder Perspectives on Chronic Wasting Disease Risk and Management on the Canadian Prairies

 

research article

 


 

Tuesday, June 19, 2012

 

*** Experimental Oral Transmission of Chronic Wasting Disease to Reindeer (Rangifer tarandus tarandus) ***

 


 

What is the risk of chronic wasting disease being introduced into Great Britain? An updated Qualitative Risk Assessment March 2016

 


 

Summary

 

The previous assessment concentrated on the incursion of disease from North America through the imports of animal feed or the movement of contaminated clothing, footwear and equipment. The results suggested that import of pet feed was a non-negligible risk, but given the unlikely contact of resident deer in GB with such non-ruminant feed, this was considered overall a negligible to very low risk. The movement of contaminated clothing, footwear or equipment (particularly hunting equipment) could pose a very low risk, although the volume of contaminated soil which would need to be ingested to give rise to an infection is likely to be higher than would be present. There is a variable level uncertainty in all these assessments.

 

The new assessment focuses on an additional potential route of entry: the importation of natural deer urine lures. The main conclusions from this assessment are:

 

In areas of North America where CWD has been reported, given that CWD is excreted in faeces, saliva, urine and blood, and survives in the environment for several years there is a medium probability that the deer urine in North America contains CWD (high uncertainty; depends on the source of deer used for production).

 

The risk of a deer in GB being infected per 30 ml bottle of urine imported from the USA is very low, albeit with high uncertainty. Overall it is concluded that the risk of at least one infection of deer in the UK with CWD per year from deer urine lures imported from the USA is medium. This assumes a high number of 30 ml bottles imported per year from all areas of the USA.

 

None of the species affected by CWD in North America are present in GB. For a British species to become infected with CWD following exposure, the dose and inherent susceptibility of the species will be important. Based on current scientific evidence Red deer (Cervus elaphus elaphus) are susceptible to CWD, Fallow deer (Dama dama) are likely to be less susceptible and Roe deer (Capreolus capreolus) have a gene conferring susceptibility. Therefore, it is likely that given exposure to an infectious dose of CWD, deer in GB could become infected with CWD.

 

Overall, the probability of importing CWD into GB from North America and causing infection in British deer is uncertain but likely to be negligible to very low via movement of deer hunters, other tourists and British servicemen and very low via imported (non-

 

2

 

ruminant) animal feed and medium for the use of lures. However, if it was imported and (a) deer did become infected with CWD, the consequences would be severe as eradication of the disease is impossible, it is clinically indistinguishable from BSE infection in deer (Dalgleish et al., 2008) and populations of wild and farmed deer would be under threat.

 

The USA has implemented a Herd Certification Programme for farmed and captive cervids. So far, 29 States are approved for HCP status (APHIS, 2015). The list includes States such as Colorado, where CWD is present, therefore it is recommended that any sourcing of such natural urine lures should be not only from States with an HCP programme, but also from a herd which is registered as being regularly tested free of CWD.

 

Animal urine is not considered a commodity which is subject to animal by-products legislation for imports. Internet sales are common and although a license would be required, there are no conditions for the safe sourcing of such products. Deer urine lures are also available in Europe and may be produced from carcases of hunted deer. The use of deer urine produced from a species not present in Europe (such as white tailed deer) is questioned for its value with native GB deer according to the British Deer Society survey.

 

Background

 


 

Thursday, April 07, 2016

 

What is the risk of chronic wasting disease being introduced into Great Britain? An updated Qualitative Risk Assessment March 2016

 


 

Friday, December 14, 2012

 

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

 

snip...

 

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

 

Animals considered at high risk for CWD include:

 

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

 

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

 

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

 

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

 

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

 

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

 

snip...

 

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

 

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

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 

What is the risk of chronic wasting disease being introduced into Great Britain? A Qualitative Risk Assessment October 2012

 


 

I strenuously once again urge the FDA and its industry constituents, to make it MANDATORY that all ruminant feed be banned to all ruminants, and this should include all cervids, as well as non-ruminants such as cats and dogs as well, as soon as possible for the following reasons...

 

31 Jan 2015 at 20:14 GMT

 

*** Ruminant feed ban for cervids in the United States? ***

 

31 Jan 2015 at 20:14 GMT

 

Terry Singeltary Sr. comment ;

 


 

Tuesday, April 19, 2016

 

Docket No. FDA-2013-N-0764 for Animal Feed Regulatory Program Standards Singeltary Comment Submission

 


 


 


 

Thursday, August 25, 2016

 

FSIS Green Bay Dressed Beef Recalls Beef Products Due To Possible Specified Risk Materials Contamination the most high risk materials for BSE TSE PRION AKA MAD COW TYPE DISEASE

 


 

In the USA, USDA et al sometimes serves SRM’s up as appetizers or horderves.

 

Monday, June 20, 2016

 

*** Specified Risk Materials SRMs BSE TSE Prion Program

 


 

Saturday, January 31, 2015

 

RAPID ADVICE 17-2014 : Evaluation of the risk for public health of casings in countries with a “negligible risk status for BSE” and on the risk of modification of the list of specified risk materials (SRM) with regard to BSE

 


 

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

 

Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3

 


 


 

CWD TSE PRION HUMAN ZOONOSIS POTENTIAL, has it already happened, and being masked as sporadic CJD? and what about iatrogenic, or the pass if forward, friendly fire mode of transmission of cwd to humans, same thing, sporadic cjd ?

 

*** 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

 

Ms. Alyssa Wetterau1, Dr. Krysten Schuler1, Dr. Elizabeth Bunting1, Dr. Hussni Mohammed1 1Cornell University

 

Chronic wasting disease (CWD) is a fatal disease of North American Cervidae. New York State (NYS, USA) successfully managed an outbreak of CWD in 2005 in both captive and wild white-tailed deer (Odocoileus virginianus) with no reoccurrence of the disease as of 2015. To attain maximum compliance and efficacy of management actions for prevention of CWD entry, understanding the varied risk perceptions will allow for targeted, proactive communication efforts to address divergences between expert-derived risk assessments and stakeholder risk perceptions. We examined perceived risks associated with CWD introduction and exposure among agricultural and wildlife agency professionals within and outside of NYS, as well as stakeholder groups (e.g., hunters and captive cervid owners). We measured perceived risk using a risk assessment questionnaire online via Qualtrics survey software and evaluated similarities within, as well as differences in, perception among participant groups. New York State biologists employed by the Department of Environmental Conservation and independent non-NYS wildlife and agricultural professionals thought CWD risks associated with captive cervids were high; captive cervid owners thought risks for wild and captive cervids were low. Agriculture and wildlife professional groups agreed on general risk perceptions. We ranked 15 individual risk hazards into high and low medium categories based on all responses. Differences between groups were most evident in hypothetical disease pathways. Any pathway involving inter-state import of live cervids received high ranking for all groups except captive cervid owners. Comparatively low risk perceptions by captive cervid operators may stem from misinformation, lack of understanding of testing programs, and indemnity payments for animal depopulation. Communication and education directed at areas of disagreement may facilitate effective disease prevention and management.

 


 


 

* No evaluation of determination of CWD risk is required for alternative livestock or captive wildlife shipped directly to slaughter or to a biosecure facility approved by the Division and the Dept. of Agriculture.

 


 

*** 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. ***

 

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

 


 

Prion 2016

 

Purchase options Price * Issue Purchase USD 198.00

 


 

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

 


 

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

 

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

 


 

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

 


 

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).***

 


 

PRION 2015 CONFERENCE FT. COLLINS CWD RISK FACTORS TO HUMANS

 

*** LATE-BREAKING ABSTRACTS PRION 2015 CONFERENCE ***

 

O18

 

Zoonotic Potential of CWD Prions

 

Liuting Qing1, Ignazio Cali1,2, Jue Yuan1, Shenghai Huang3, Diane Kofskey1, Pierluigi Gambetti1, Wenquan Zou1, Qingzhong Kong1 1Case Western Reserve University, Cleveland, Ohio, USA, 2Second University of Naples, Naples, Italy, 3Encore Health Resources, Houston, Texas, USA

 

*** These results indicate that the CWD prion has the potential to infect human CNS and peripheral lymphoid tissues and that there might be asymptomatic human carriers of CWD infection.

 

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

 

***These results indicate that the CWD prion has the potential to infect human CNS and peripheral lymphoid tissues and that there might be asymptomatic human carriers of CWD infection.***

 

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

 

P.105: RT-QuIC models trans-species prion transmission

 

Kristen Davenport, Davin Henderson, Candace Mathiason, and Edward Hoover Prion Research Center; Colorado State University; Fort Collins, CO USA

 

Conversely, FSE maintained sufficient BSE characteristics to more efficiently convert bovine rPrP than feline rPrP. Additionally, human rPrP was competent for conversion by CWD and fCWD.

 

***This insinuates that, at the level of protein:protein interactions, the barrier preventing transmission of CWD to humans is less robust than previously estimated.

 

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

 

***This insinuates that, at the level of protein:protein interactions, the barrier preventing transmission of CWD to humans is less robust than previously estimated.***

 

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

 


 

*** PRICE OF CWD TSE PRION POKER GOES UP 2014 ***

 

Transmissible Spongiform Encephalopathy TSE PRION update January 2, 2014

 

*** chronic wasting disease, there was no absolute barrier to conversion of the human prion protein.

 

*** Furthermore, the form of human PrPres produced in this in vitro assay when seeded with CWD, resembles that found in the most common human prion disease, namely sCJD of the MM1 subtype.

 


 


 

*** 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).***

 


 

*** 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.

 


 

***********CJD REPORT 1994 increased risk for consumption of veal and venison and lamb***********

 

CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL REPORT AUGUST 1994

 

Consumption of venison and veal was much less widespread among both cases and controls. For both of these meats there was evidence of a trend with increasing frequency of consumption being associated with increasing risk of CJD. (not nvCJD, but sporadic CJD...tss)

 

These associations were largely unchanged when attention was restricted to pairs with data obtained from relatives. ...

 

Table 9 presents the results of an analysis of these data.

 

There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).

 

Individuals reported to eat veal on average at least once a year appear to be at 13 TIMES THE RISK of individuals who have never eaten veal.

 

There is, however, a very wide confidence interval around this estimate. There is no strong evidence that eating veal less than once per year is associated with increased risk of CJD (p = 0.51).

 

The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).

 

There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY OF LAMB EATING (p = 0.02).

 

The evidence for such an association between beef eating and CJD is weaker (p = 0.14). When only controls for whom a relative was interviewed are included, this evidence becomes a little STRONGER (p = 0.08).

 

snip...

 

It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).

 

snip...

 

In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...

 

snip...

 

In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)

 

snip...see full report ;

 


 

CJD9/10022

 

October 1994

 

Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane BerksWell Coventry CV7 7BZ

 

Dear Mr Elmhirst,

 

CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT

 

Thank you for your recent letter concerning the publication of the third annual report from the CJD Surveillance Unit. I am sorry that you are dissatisfied with the way in which this report was published.

 

The Surveillance Unit is a completely independant outside body and the Department of Health is committed to publishing their reports as soon as they become available. In the circumstances it is not the practice to circulate the report for comment since the findings of the report would not be amended. In future we can ensure that the British Deer Farmers Association receives a copy of the report in advance of publication.

 

The Chief Medical Officer has undertaken to keep the public fully informed of the results of any research in respect of CJD. This report was entirely the work of the unit and was produced completely independantly of the the Department.

 

The statistical results reqarding the consumption of venison was put into perspective in the body of the report and was not mentioned at all in the press release. Media attention regarding this report was low key but gave a realistic presentation of the statistical findings of the Unit. This approach to publication was successful in that consumption of venison was highlighted only once by the media ie. in the News at one television proqramme.

 

I believe that a further statement about the report, or indeed statistical links between CJD and consumption of venison, would increase, and quite possibly give damaging credence, to the whole issue. From the low key media reports of which I am aware it seems unlikely that venison consumption will suffer adversely, if at all.

 


 

Monday, May 02, 2016

 

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

 


 

*** PRION 2014 CONFERENCE CHRONIC WASTING DISEASE CWD

 


 

*** PPo3-7: Prion Transmission from Cervids to Humans is Strain-dependent

 

*** Here we report that a human prion strain that had adopted the cervid prion protein (PrP) sequence through passage in cervidized transgenic mice efficiently infected transgenic mice expressing human PrP,

 

*** indicating that the species barrier from cervid to humans is prion strain-dependent and humans can be vulnerable to novel cervid prion strains.

 

PPo2-27:

 

Generation of a Novel form of Human PrPSc by Inter-species Transmission of Cervid Prions

 

*** Our findings suggest that CWD prions have the capability to infect humans, and that this ability depends on CWD strain adaptation, implying that the risk for human health progressively increases with the spread of CWD among cervids.

 

PPo2-7:

 

Biochemical and Biophysical Characterization of Different CWD Isolates

 

*** The data presented here substantiate and expand previous reports on the existence of different CWD strains.

 


 

Envt.07:

 

Pathological Prion Protein (PrPTSE) in Skeletal Muscles of Farmed and Free Ranging White-Tailed Deer Infected with Chronic Wasting Disease

 

***The presence and seeding activity of PrPTSE in skeletal muscle from CWD-infected cervids suggests prevention of such tissue in the human diet as a precautionary measure for food safety, pending on further clarification of whether CWD may be transmissible to humans.

 


 

>>>CHRONIC WASTING DISEASE , THERE WAS NO ABSOLUTE BARRIER TO CONVERSION OF THE HUMAN PRION PROTEIN<<<

 

*** PRICE OF CWD TSE PRION POKER GOES UP 2014 ***

 

Transmissible Spongiform Encephalopathy TSE PRION update January 2, 2014

 

Wednesday, January 01, 2014

 

Molecular Barriers to Zoonotic Transmission of Prions

 

*** chronic wasting disease, there was no absolute barrier to conversion of the human prion protein.

 

*** Furthermore, the form of human PrPres produced in this in vitro assay when seeded with CWD, resembles that found in the most common human prion disease, namely sCJD of the MM1 subtype.

 


 


 

Envt.07:

 

Pathological Prion Protein (PrPTSE) in Skeletal Muscles of Farmed and Free Ranging White-Tailed Deer Infected with Chronic Wasting Disease

 

***The presence and seeding activity of PrPTSE in skeletal muscle from CWD-infected cervids suggests prevention of such tissue in the human diet as a precautionary measure for food safety, pending on further clarification of whether CWD may be transmissible to humans.

 

Yet, it has to be noted that our assessments of PrPTSE levels in skeletal muscles were based on findings in presumably pre- or subclinically infected animals. Therefore, the concentration of PrPTSE in skeletal muscles of WTD with clinically manifest CWD may possibly exceed our estimate which refers to clinically inconspicuous animals that are more likely to enter the human food chain. Our tissue blot findings in skeletal muscles from CWD-infected WTD would be consistent with an anterograde spread of CWD prions via motor nerve fibres to muscle tissue (figure 4A). Similar neural spreading pathways of muscle infection were previously found in hamsters orally challenged with scrapie [28] and suggested by the detection of PrPTSE in muscle fibres and muscle-associated nerve fascicles of clinically-ill non-human primates challenged with BSE prions [29]. Whether the absence of detectable PrPTSE in myofibers observed in our study is a specific feature of CWD in WTD, or was due to a pre- or subclinical stage of infection in the examined animals, remains to be established. In any case, our observations support previous findings suggesting the precautionary prevention of muscle tissue from CWD-infected WTD in the human diet, and highlight the need to comprehensively elucidate of whether CWD may be transmissible to humans. While the understanding of TSEs in cervids has made substantial progress during the past few years, the assessment and management of risks possibly emanating from prions in skeletal muscles of CWD-infected cervids requires further research.

 


 


 

Prions in Skeletal Muscles of Deer with Chronic Wasting Disease Rachel C. Angers1,*, Shawn R. Browning1,*,†, Tanya S. Seward2, Christina J. Sigurdson4,‡, Michael W. Miller5, Edward A. Hoover4, Glenn C. Telling1,2,3,§ + Author Affiliations

 

1 Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY 40536, USA. 2 Sanders Brown Center on Aging, University of Kentucky, Lexington, KY 40536, USA. 3 Department of Neurology, University of Kentucky, Lexington, KY 40536, USA. 4 Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA. 5 Colorado Division of Wildlife, Wildlife Research Center, Fort Collins, CO 80526, USA. ↵§ To whom correspondence should be addressed. E-mail: gtell2@uky.edu ↵* These authors contributed equally to this work.

 

↵† Present address: Department of Infectology, Scripps Research Institute, 5353 Parkside Drive, RF-2, Jupiter, FL 33458, USA.

 

↵‡ Present address: Institute of Neuropathology, University of Zurich, Schmelzbergstrasse 12, 8091 Zurich, Switzerland.

 

Abstract The emergence of chronic wasting disease (CWD) in deer and elk in an increasingly wide geographic area, as well as the interspecies transmission of bovine spongiform encephalopathy to humans in the form of variant Creutzfeldt Jakob disease, have raised concerns about the zoonotic potential of CWD. Because meat consumption is the most likely means of exposure, it is important to determine whether skeletal muscle of diseased cervids contains prion infectivity. Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.

 


 

Exotic Meats USA Announces Urgent Statewide Recall of Elk Tenderloin Because It May Contain Meat Derived From An Elk Confirmed To Have Chronic Wasting Disease

 

Contact: Exotic Meats USA 1-800-680-4375

 

FOR IMMEDIATE RELEASE -- February 9, 2009 -- Exotic Meats USA of San Antonio, TX is initiating a voluntary recall of Elk Tenderloin because it may contain meat derived from an elk confirmed to have Chronic Wasting Disease (CWD). The meat with production dates of December 29, 30 and 31, 2008 was purchased from Sierra Meat Company in Reno, NV. The infected elk came from Elk Farm LLC in Pine Island, MN and was among animals slaughtered and processed at USDA facility Noah’s Ark Processors LLC.

 

Chronic Wasting Disease (CWD) is a fatal brain and nervous system disease found in elk and deer. The disease is caused by an abnormally shaped protein called a prion, which can damage the brain and nerves of animals in the deer family. Currently, it is believed that the prion responsible for causing CWD in deer and elk is not capable of infecting humans who eat deer or elk contaminated with the prion, but the observation of animal-to-human transmission of other prion-mediated diseases, such as bovine spongiform encephalopathy (BSE), has raised a theoretical concern regarding the transmission of CWD from deer or elk to humans. At the present time, FDA believes the risk of becoming ill from eating CWD-positive elk or deer meat is remote. However, FDA strongly advises consumers to return the product to the place of purchase, rather than disposing of it themselves, due to environmental concerns.

 

Exotic Meats USA purchased 1 case of Elk Tenderloins weighing 16.9 lbs. The Elk Tenderloin was sold from January 16 – 27, 2009. The Elk Tenderloins was packaged in individual vacuum packs weighing approximately 3 pounds each. A total of six packs of the Elk Tenderloins were sold to the public at the Exotic Meats USA retail store. Consumers who still have the Elk Tenderloins should return the product to Exotic Meats USA at 1003 NE Loop 410, San Antonio, TX 78209. Customers with concerns or questions about the Voluntary Elk Recall can call 1-800-680-4375. The safety of our customer has always been and always will be our number one priority.

 

Exotic Meats USA requests that for those customers who have products with the production dates in question, do not consume or sell them and return them to the point of purchase. Customers should return the product to the vendor. The vendor should return it to the distributor and the distributor should work with the state to decide upon how best to dispose. If the consumer is disposing of the product he/she should consult with the local state EPA office.

 

#

 


 

COLORADO: Farmer's market meat recalled after testing positive for CWD

 

24.dec.08 9News.com Jeffrey Wolf

 

Elk meat that was sold at a farmer's market is being recalled because tests show it was infected with chronic wasting disease. The Boulder County Health Department and Colorado Department of Public Health and Environment issued the recall Wednesday after the meat was sold at the Boulder County Fairgrounds on Dec. 13. Although there isn't any human health risk connected with CWD, the recalled was issued as a precaution. About 15 elk were bought from a commercial ranch in Colorado in early December and processed at a licensed plant. All 15 were tested for CWD and one came up positive. The labeling on the product would have the following information: *Seller: High Wire Ranch *The type of cut: "chuck roast," "arm roast," "flat iron," "ribeye steak," "New York steak," "tenderloin," "sirloin tip roast," "medallions" or "ground meat." *Processor: Cedaredge Processing *The USDA triangle containing the number "34645" People with questions about this meat can contact John Pape, epidemiologist at the Colorado Department of Public Health and Environment at 303-692-2628.

 


 

COULD NOT FIND any warning or recalls on these two sites confirming their recall of CWD infected meat. ...TSS

 


 


 

Wednesday, April 06, 2011

 

Presence and Seeding Activity of Pathological Prion Protein (PrPTSE) in Skeletal Muscles of White-Tailed Deer Infected with Chronic Wasting Disease

 


 

Prion Infectivity in Fat of Deer with Chronic Wasting Disease

 

Brent Race,# Kimberly Meade-White,# Richard Race, and Bruce Chesebro* Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, Montana 59840

 

Received 2 June 2009/ Accepted 24 June 2009

 

ABSTRACT Top ABSTRACT TEXT REFERENCES

 

Chronic wasting disease (CWD) is a neurodegenerative prion disease of cervids. Some animal prion diseases, such as bovine spongiform encephalopathy, can infect humans; however, human susceptibility to CWD is unknown. In ruminants, prion infectivity is found in central nervous system and lymphoid tissues, with smaller amounts in intestine and muscle. In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.

 

snip...

 

The highest risk of human contact with CWD might be through exposure to high-titer CNS tissue through accidental skin cuts or corneal contact at the time of harvest and butchering. However, the likelihood of a human consuming fat infected with a low titer of the CWD agent is much higher. It is impossible to remove all the fat present within muscle tissue, and fat consumption is inevitable when eating meat. Of additional concern is the fact that meat from an individual deer harvested by a hunter is typically consumed over multiple meals by the same group of people. These individuals would thus have multiple exposures to the CWD agent over time, which might increase the chance for transfer of infection.

 

In the Rocky Mountain region of North America, wild deer are subject to predation by wolves, coyotes, bears, and mountain lions. Although canines such as wolves and coyotes are not known to be susceptible to prion diseases, felines definitely are susceptible to BSE (9) and might also be infected by the CWD agent. Deer infected with the CWD agent are more likely to be killed by predators such as mountain lions (11). Peripheral tissues, including lymph nodes, muscle, and fat, which harbor prion infectivity are more accessible for consumption than CNS tissue, which has the highest level of infectivity late in disease. Therefore, infectivity in these peripheral tissues may be important in potential cross-species CWD transmissions in the wild.

 

The present finding of CWD infectivity in deer fat tissue raises the possibility that prion infectivity might also be found in fat tissue of other infected ruminants, such as sheep and cattle, whose fat and muscle tissues are more widely distributed in both the human and domestic-animal food chains. Although the infectivity in fat tissues is low compared to that in the CNS, there may be significant differences among species and between prion strains. Two fat samples from BSE agent-infected cattle were reported to be negative by bioassay in nontransgenic RIII mice (3, 6). However, RIII mice are 10,000-fold-less sensitive to BSE agent infection than transgenic mice expressing bovine PrP (4). It would be prudent to carry out additional infectivity assays on fat from BSE agent-infected cattle and scrapie agent-infected sheep using appropriate transgenic mice or homologous species to determine the risk from these sources.

 


 

0C7.04

 

North American Cervids Harbor Two Distinct CWD Strains

 

Authors

 

Angers, R. Seward, T, Napier, D., Browning, S., Miller, M., Balachandran A., McKenzie, D., Hoover, E., Telling, G. 'University of Kentucky; Colorado Division of Wildlife, Canadian Food Inspection Agency; University Of Wisconsin; Colorado State University.

 

Content

 

Despite the increasing geographic distribution and host range of CWD, little is known about the prion strain(s) responsible for distinct outbreaks of the disease. To address this we inoculated CWD-susceptible Tg(CerPrP)1536+/· mice with 29 individual prion samples from various geographic locations in North America. Upon serial passage, intrastudy incubation periods consistently diverged and clustered into two main groups with means around 210 and 290 days, with corresponding differences in neuropathology. Prion strain designations were utilized to distinguish between the two groups: Type I CWD mice succumbed to disease in the 200 day range and displayed a symmetrical pattern of vacuolation and PrPSc deposition, whereas Type II CWD mice succumbed to disease near 300 days and displayed a strikingly different pattern characterized by large local accumulations of florid plaques distributed asymmetrically. Type II CWD bears a striking resemblance to unstable parental scrapie strains such as 87A which give rise to stable, short incubation period strains such as ME7 under certain passage conditions. In agreement, the only groups of CWD-inoculated mice with unwavering incubation periods were those with Type I CWD. Additionally, following endpoint titration of a CWD sample, Type I CWD could be recovered only at the lowest dilution tested (10-1), whereas Type II CWD was detected in mice inoculated with all dilutions resulting in disease. Although strain properties are believed to be encoded in the tertiary structure of the infectious prion protein, we found no biochemical differences between Type I and Type II CWD. Our data confirm the co·existence of two distinct prion strains in CWD-infected cervids and suggest that Type II CWD is the parent strain of Type I CWD.

 

see page 29, and see other CWD studies ;

 


 

Sunday, November 23, 2008

 

PRION October 8th - 10th 2008 Book of Abstracts

 


 

ADAPTATION OF CHRONIC WASTING DISEASE (CWD) INTO HAMSTERS, EVIDENCE OF A WISCONSIN STRAIN OF CWD

 

Chad Johnson1, Judd Aiken2,3,4 and Debbie McKenzie4,5 1 Department of Comparative Biosciences, University of Wisconsin, Madison WI, USA 53706 2 Department of Agriculture, Food and Nutritional Sciences, 3 Alberta Veterinary Research Institute, 4.Center for Prions and Protein Folding Diseases, 5 Department of Biological Sciences, University of Alberta, Edmonton AB, Canada T6G 2P5

 

The identification and characterization of prion strains is increasingly important for the diagnosis and biological definition of these infectious pathogens. Although well-established in scrapie and, more recently, in BSE, comparatively little is known about the possibility of prion strains in chronic wasting disease (CWD), a disease affecting free ranging and captive cervids, primarily in North America. We have identified prion protein variants in the white-tailed deer population and demonstrated that Prnp genotype affects the susceptibility/disease progression of white-tailed deer to CWD agent. The existence of cervid prion protein variants raises the likelihood of distinct CWD strains. Small rodent models are a useful means of identifying prion strains. We intracerebrally inoculated hamsters with brain homogenates and phosphotungstate concentrated preparations from CWD positive hunter-harvested (Wisconsin CWD endemic area) and experimentally infected deer of known Prnp genotypes. These transmission studies resulted in clinical presentation in primary passage of concentrated CWD prions. Subclinical infection was established with the other primary passages based on the detection of PrPCWD in the brains of hamsters and the successful disease transmission upon second passage. Second and third passage data, when compared to transmission studies using different CWD inocula (Raymond et al., 2007) indicate that the CWD agent present in the Wisconsin white-tailed deer population is different than the strain(s) present in elk, mule-deer and white-tailed deer from the western United States endemic region.

 


 

Tuesday, December 16, 2014

 

Evidence for zoonotic potential of ovine scrapie prions

 

Hervé Cassard,1, n1 Juan-Maria Torres,2, n1 Caroline Lacroux,1, Jean-Yves Douet,1, Sylvie L. Benestad,3, Frédéric Lantier,4, Séverine Lugan,1, Isabelle Lantier,4, Pierrette Costes,1, Naima Aron,1, Fabienne Reine,5, Laetitia Herzog,5, Juan-Carlos Espinosa,2, Vincent Beringue5, & Olivier Andréoletti1, Affiliations Contributions Corresponding author Journal name: Nature Communications Volume: 5, Article number: 5821 DOI: doi:10.1038/ncomms6821 Received 07 August 2014 Accepted 10 November 2014 Published 16 December 2014 Article tools Citation Reprints Rights & permissions Article metrics

 

Abstract

 

Although Bovine Spongiform Encephalopathy (BSE) is the cause of variant Creutzfeldt Jakob disease (vCJD) in humans, the zoonotic potential of scrapie prions remains unknown. Mice genetically engineered to overexpress the human ​prion protein (tgHu) have emerged as highly relevant models for gauging the capacity of prions to transmit to humans. These models can propagate human prions without any apparent transmission barrier and have been used used to confirm the zoonotic ability of BSE. Here we show that a panel of sheep scrapie prions transmit to several tgHu mice models with an efficiency comparable to that of cattle BSE. The serial transmission of different scrapie isolates in these mice led to the propagation of prions that are phenotypically identical to those causing sporadic CJD (sCJD) in humans. These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.

 

Subject terms: Biological sciences• Medical research At a glance

 


 

*** 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.

 


 

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

 

Taylor & Francis

 

Prion 2016 Animal Prion Disease Workshop Abstracts

 

WS-01: Prion diseases in animals and zoonotic potential

 

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

 

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

 

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

 

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

 

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

 

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

 

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

 


 


 

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

 

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

 

snip...

 

R. BRADLEY

 


 

1978 SCRAPIE IN CONFIDENCE SCJD

 


 


 


 


 


 


 


 


 


 

1979

 

SILENCE ON CJD AND SCRAPIE

 

1980

 

SILENCE ON CJD AND SCRAPIE

 

*** 1981 NOVEMBER

 


 


 

Thursday, August 04, 2016

 

*** MEETING ON THE FEASIBILITY OF CARRYING OUT EPIDEMIOLOGICAL STUDIES ON CREUTZFELDT JAKOB DISEASE 1978 THE SCRAPIE FILES IN CONFIDENCE CONFIDENTIAL SCJD

 


 

2016

 

SCRAPIE AND CWD ZOONOSIS

 

PRION 2016 CONFERENCE 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

 


 

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

 

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

 


 

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

 

Emmanuel E. Comoy , Jacqueline Mikol , Sophie Luccantoni-Freire , Evelyne Correia , Nathalie Lescoutra-Etchegaray , Valérie Durand , Capucine Dehen , Olivier Andreoletti , Cristina Casalone , Juergen A. Richt , Justin J. Greenlee , Thierry Baron , Sylvie L. Benestad , Paul Brown & Jean-Philippe Deslys

 

Abstract

 

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

 

snip...

 

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

 

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

 


 


 

2015

 

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.

 

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

 


 

Saturday, May 28, 2016

 

*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***

 


 

What is the risk of chronic wasting disease being introduced into Great Britain? An updated Qualitative Risk Assessment March 2016

 


 

Summary

 

The previous assessment concentrated on the incursion of disease from North America through the imports of animal feed or the movement of contaminated clothing, footwear and equipment. The results suggested that import of pet feed was a non-negligible risk, but given the unlikely contact of resident deer in GB with such non-ruminant feed, this was considered overall a negligible to very low risk. The movement of contaminated clothing, footwear or equipment (particularly hunting equipment) could pose a very low risk, although the volume of contaminated soil which would need to be ingested to give rise to an infection is likely to be higher than would be present. There is a variable level uncertainty in all these assessments.

 

The new assessment focuses on an additional potential route of entry: the importation of natural deer urine lures. The main conclusions from this assessment are:

 

 In areas of North America where CWD has been reported, given that CWD is excreted in faeces, saliva, urine and blood, and survives in the environment for several years there is a medium probability that the deer urine in North America contains CWD (high uncertainty; depends on the source of deer used for production).

 

 The risk of a deer in GB being infected per 30 ml bottle of urine imported from the USA is very low, albeit with high uncertainty. Overall it is concluded that the risk of at least one infection of deer in the UK with CWD per year from deer urine lures imported from the USA is medium. This assumes a high number of 30 ml bottles imported per year from all areas of the USA.

 

 None of the species affected by CWD in North America are present in GB. For a British species to become infected with CWD following exposure, the dose and inherent susceptibility of the species will be important. Based on current scientific evidence Red deer (Cervus elaphus elaphus) are susceptible to CWD, Fallow deer (Dama dama) are likely to be less susceptible and Roe deer (Capreolus capreolus) have a gene conferring susceptibility. Therefore, it is likely that given exposure to an infectious dose of CWD, deer in GB could become infected with CWD.

 

Overall, the probability of importing CWD into GB from North America and causing infection in British deer is uncertain but likely to be negligible to very low via movement of deer hunters, other tourists and British servicemen and very low via imported (non-

 

2

 

ruminant) animal feed and medium for the use of lures. However, if it was imported and (a) deer did become infected with CWD, the consequences would be severe as eradication of the disease is impossible, it is clinically indistinguishable from BSE infection in deer (Dalgleish et al., 2008) and populations of wild and farmed deer would be under threat.

 

The USA has implemented a Herd Certification Programme for farmed and captive cervids. So far, 29 States are approved for HCP status (APHIS, 2015). The list includes States such as Colorado, where CWD is present, therefore it is recommended that any sourcing of such natural urine lures should be not only from States with an HCP programme, but also from a herd which is registered as being regularly tested free of CWD.

 

Animal urine is not considered a commodity which is subject to animal by-products legislation for imports. Internet sales are common and although a license would be required, there are no conditions for the safe sourcing of such products. Deer urine lures are also available in Europe and may be produced from carcases of hunted deer. The use of deer urine produced from a species not present in Europe (such as white tailed deer) is questioned for its value with native GB deer according to the British Deer Society survey.

 

Background

 


 

Thursday, April 07, 2016

 

What is the risk of chronic wasting disease being introduced into Great Britain? An updated Qualitative Risk Assessment March 2016

 


 

Friday, December 14, 2012

 

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

 

snip...

 

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

 

Animals considered at high risk for CWD include:

 

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

 

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

 

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

 

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

 

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

 

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

 

snip...

 

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

 

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

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 

What is the risk of chronic wasting disease being introduced into Great Britain? A Qualitative Risk Assessment October 2012

 


 

I strenuously once again urge the FDA and its industry constituents, to make it MANDATORY that all ruminant feed be banned to all ruminants, and this should include all cervids, as well as non-ruminants such as cats and dogs as well, as soon as possible for the following reasons...

 

31 Jan 2015 at 20:14 GMT

 

*** Ruminant feed ban for cervids in the United States? ***

 

31 Jan 2015 at 20:14 GMT

 

Terry Singeltary Sr. comment ;

 


 

Tuesday, April 19, 2016

 

Docket No. FDA-2013-N-0764 for Animal Feed Regulatory Program Standards Singeltary Comment Submission

 


 


 


 

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

 

Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3

 


 

Friday, August 14, 2015

 

*** Susceptibility of cattle to the agent of chronic wasting disease from elk after intracranial inoculation ***

 


 

Saturday, May 28, 2016

 

*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***

 


 

Experimental Oral Transmission of Chronic Wasting Disease to Reindeer (Rangifer tarandus tarandus)

 

Gordon B. Mitchell1, Christina J. Sigurdson2,3, Katherine I. O’Rourke4, James Algire1, Noel P. Harrington1, Ines Walther1, Terry R. Spraker5, Aru Balachandran1*

 

1 National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa Laboratory – Fallowfield, Ottawa, Ontario, Canada,

 

2 Departments of Pathology and Medicine, University of California, San Diego, La Jolla, California, United States of America, 3 Department of Pathology, Microbiology and Immunology, University of California, Davis, California, United States of America, 4 Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America, 5 Veterinary Diagnostic Laboratory, Colorado State University, Fort Collins, Colorado, United States of America

 

Abstract

 

Chronic wasting disease (CWD), a transmissible spongiform encephalopathy of cervids, remains prevalent in North American elk, white-tailed deer and mule deer. A natural case of CWD in reindeer (Rangifer tarandus tarandus) has not been reported despite potential habitat overlap with CWD-infected deer or elk herds. This study investigates the experimental transmission of CWD from elk or white-tailed deer to reindeer by the oral route of inoculation. Ante-mortem testing of the three reindeer exposed to CWD from white-tailed deer identified the accumulation of pathological PrP (PrPCWD) in the recto-anal mucosa associated lymphoid tissue (RAMALT) of two reindeer at 13.4 months post-inoculation. Terminal CWD occurred in the two RAMALT-positive reindeer at 18.5 and 20 months post-inoculation while one other reindeer in the white-tailed deer CWD inoculum group and none of the 3 reindeer exposed to elk CWD developed disease. Tissue distribution analysis of PrPCWD in CWD-affected reindeer revealed widespread deposition in central and peripheral nervous systems, lymphoreticular tissues, the gastrointestinal tract, neuroendocrine tissues and cardiac muscle. Analysis of prion protein gene (PRNP) sequences in the 6 reindeer identified polymorphisms at residues 2 (V/M), 129 (G/S), 138 (S/N) and 169 (V/M). These findings demonstrate that (i) a sub-population of reindeer are susceptible to CWD by oral inoculation implicating the potential for transmission to other Rangifer species, and (ii) certain reindeer PRNP polymorphisms may be protective against CWD infection.

 

 snip...

 

 The importance of Rangifer species to the culture of aboriginal peoples cannot be underestimated with many components of hunted animals being consumed as food. Although relatively limited in comparison to elk and deer industries in North America, reindeer and caribou farming does occur, producing consumables such as meat, hides and antler velvet. The human health risks of consuming meat or other products derived from CWD-infected animals remain uncertain, although epidemiological evidence indicates transmission has not yet occurred [30,31,32] and transgenic mouse studies suggest the risk is remote in humans expressing common PRNP sequences [33,34,35]. The finding that CWD can be transmitted to squirrel monkeys by intracranial inoculation [36] raises concern for human transmissibility, however a study in macaques failed to demonstrate transmission after 70 months [37]. Since prion strains may undergo changes in transmission characteristics following passage through different species and strain selection pressures can be exerted by host genetic factors during passage within a species [24,38,39,40], caution is warranted when predicting the risks of CWD transmission from reindeer to other species.

 

This is the first evidence of CWD transmission to the sub-species Rangifer tarandus tarandus, implicating the potential for transmission to others in this genus. Current diagnostic tests, including antemortem RAMALT testing, appear capable of detecting CWD in Rangifer species and increased surveillance would be required to determine if natural transmission has indeed occurred. Additional studies are ongoing to chart the distribution of infectivity during the course of disease and determine the influence of PRNP polymorphisms in disease susceptibility.

 

Citation: Mitchell GB, Sigurdson CJ, O’Rourke KI, Algire J, Harrington NP, et al. (2012) Experimental Oral Transmission of Chronic Wasting Disease to Reindeer (Rangifer tarandus tarandus). PLoS ONE 7(6): e39055. doi:10.1371/journal.pone.0039055

 

Editor: Anthony E. Kincaid, Creighton University, United States of America

 

Received May 4, 2012; Accepted May 15, 2012; Published June 18, 2012

 

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

 

Funding: This work was supported by the Canadian Food Inspection Agency and Agriculture and Agri-Food Canada under C00233, the United States

 

Department of Agriculture Agricultural Research Service under CRIS 5348-32000-026-00-D and the United States National Institutes of Health under NS069566 and U54AI0359. 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: Aru.Balachandran@inspection.gc.ca

 


 

 THANK YOU PLOS FOR OPEN ACCESS FOR THE LAYPEOPLE, such as myself. ...TSS

 

 natural cases of CWD in eight Sika deer (Cervus nippon) and five Sika/red deer crossbreeds Korea and Experimental oral transmission to red deer (Cervus elaphus elaphus)

 

SCWDS BRIEFS

 

A Quarterly Newsletter from the Southeastern Cooperative Wildlife Disease Study College of Veterinary Medicine The University of Georgia Athens, Georgia 30602

 

Volume 27 January 2012 Number 4

 

Red deer susceptibility to CWD via oral inoculation was demonstrated in a study conducted by collaborators from the U.S. and Canada. Red deer developed clinical signs and had spongiform changes in the brain when euthanatized at 20 MPI. The CWD prion was detectable in neural and lymphoid tissues, endocrine organs, cardiac muscle, nasal mucosa, and other tissues. Although field cases of CWD in red deer have not been reported, results of this study indicate that it could occur, which is not surprising given that elk and red deer are subspecies of Cervus elaphus. The results of this study can be found in the Canadian Veterinary Journal 51: 169-178.

 

In addition, it was reported in May 2011 that natural cases of CWD were found in eight Sika deer (Cervus nippon) and five Sika/red deer crossbreeds during epidemiological investigations of CWD cases in captive elk in Korea.

 


 

May 2011 natural cases of CWD were found in eight Sika deer (Cervus nippon) and five Sika/red deer crossbreeds during epidemiological investigations of CWD cases in captive elk in Korea

 

Friday, May 13, 2011

 

Chronic Wasting Disease (CWD) outbreaks and surveillance program in the Republic of Korea Chronic Wasting Disease (CWD) outbreaks and surveillance program in the Republic of Korea

 

Hyun-Joo Sohn, Yoon-Hee Lee, Min-jeong Kim, Eun-Im Yun, Hyo-Jin Kim, Won-Yong Lee, Dong-Seob Tark, In- Soo Cho, Foreign Animal Disease Research Division, National Veterinary Research and Quarantine Service, Republic of Korea

 

Chronic wasting disease (CWD) has been recognized as an important prion disease in native North America deer and Rocky mountain elks. The disease is a unique member of the transmissible spongiform encephalopathies (TSEs), which naturally affects only a few species. CWD had been limited to USA and Canada until 2000. On 28 December 2000, information from the Canadian government showed that a total of 95 elk had been exported from farms with CWD to Korea. These consisted of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72 elk in 1997, which had been held in pre export quarantine at the “source farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD surveillance program was initiated by the Ministry of Agriculture and Forestry (MAF) in 2001. All elks imported in 1997 were traced back, however elks imported in 1994 were impossible to identify. CWD control measures included stamping out of all animals in the affected farm, and thorough cleaning and disinfection of the premises. In addition, nationwide clinical surveillance of Korean native cervids, and improved measures to ensure reporting of CWD suspect cases were implemented. Total of 9 elks were found to be affected. CWD was designated as a notifiable disease under the Act for Prevention of Livestock Epidemics in 2002. Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and 2005. Since February of 2005, when slaughtered elks were found to be positive, all slaughtered cervid for human consumption at abattoirs were designated as target of the CWD surveillance program. Currently, CWD laboratory testing is only conducted by National Reference Laboratory on CWD, which is the Foreign Animal Disease Division (FADD) of National Veterinary Research and Quarantine Service (NVRQS). In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the human consumption was confirmed as positive. Consequently, all cervid – 54 elks, 41 Sika deer and 5 Albino deer – were culled and one elk was found to be positive. Epidemiological investigations were conducted by Veterinary Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary services. Epidemiologically related farms were found as 3 farms and all cervid at these farms were culled and subjected to CWD diagnosis. Three elks and 5 crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2. All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and confirmed as negative. Further epidemiological investigations showed that these CWD outbreaks were linked to the importation of elks from Canada in 1994 based on circumstantial evidences. In December 2010, one elk was confirmed as positive at Farm 5. Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer – were culled and one Manchurian Sika deer and seven Sika deer were found to be positive. This is the first report of CWD in these sub-species of deer. Epidemiological investigations found that the owner of the Farm 2 in CWD outbreaks in July 2010 had co-owned the Farm 5. In addition, it was newly revealed that one positive elk was introduced from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed (species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as negative. : Corresponding author: Dr. Hyun-Joo Sohn (+82-31-467-1867, E-mail: shonhj@korea.kr)

 

2011 Pre-congress Workshop: TSEs in animals and their environment 5

 


 


 


 

Friday, May 13, 2011

 

Chronic Wasting Disease (CWD) outbreaks and surveillance program in the Republic of Korea

 


 

Tuesday, June 19, 2012

 

Experimental Oral Transmission of Chronic Wasting Disease to Reindeer (Rangifer tarandus tarandus)

 


 

I urge everyone to watch this video closely...terry

 

*** you can see video here and interview with Jeff's Mom, and scientist telling you to test everything and potential risk factors for humans ***

 


 

Using in vitro prion replication for high sensitive detection of prions and prionlike proteins and for understanding mechanisms of transmission.

 

Claudio Soto

 

Mitchell Center for Alzheimer's diseases and related Brain disorders, Department of Neurology, University of Texas Medical School at Houston.

 

Prion and prion-like proteins are misfolded protein aggregates with the ability to selfpropagate to spread disease between cells, organs and in some cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m encephalopathies (TSEs), prions are mostly composed by a misfolded form of the prion protein (PrPSc), which propagates by transmitting its misfolding to the normal prion protein (PrPC). The availability of a procedure to replicate prions in the laboratory may be important to study the mechanism of prion and prion-like spreading and to develop high sensitive detection of small quantities of misfolded proteins in biological fluids, tissues and environmental samples. Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient methodology to mimic prion replication in the test tube. PMCA is a platform technology that may enable amplification of any prion-like misfolded protein aggregating through a seeding/nucleation process. In TSEs, PMCA is able to detect the equivalent of one single molecule of infectious PrPSc and propagate prions that maintain high infectivity, strain properties and species specificity. Using PMCA we have been able to detect PrPSc in blood and urine of experimentally infected animals and humans affected by vCJD with high sensitivity and specificity. Recently, we have expanded the principles of PMCA to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to study the utility of this technology to detect Aβ and α-syn aggregates in samples of CSF and blood from patients affected by these diseases.

 

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

 

***Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.

 

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

 

Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis.

 


 

see ;

 

with CWD TSE Prions, I am not sure there is any absolute yet, other than what we know with transmission studies, and we know tse prion kill, and tse prion are bad. science shows to date, that indeed soil, dirt, some better than others, can act as a carrier. same with objects, farm furniture. take it with how ever many grains of salt you wish, or not. if load factor plays a role in the end formula, then everything should be on the table, in my opinion. see ;

 

***Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.

 

Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis.

 


 

see ;

 


 

Oral Transmissibility of Prion Disease Is Enhanced by Binding to Soil Particles

 

Author Summary

 

Transmissible spongiform encephalopathies (TSEs) are a group of incurable neurological diseases likely caused by a misfolded form of the prion protein. TSEs include scrapie in sheep, bovine spongiform encephalopathy (‘‘mad cow’’ disease) in cattle, chronic wasting disease in deer and elk, and Creutzfeldt-Jakob disease in humans. Scrapie and chronic wasting disease are unique among TSEs because they can be transmitted between animals, and the disease agents appear to persist in environments previously inhabited by infected animals. Soil has been hypothesized to act as a reservoir of infectivity and to bind the infectious agent. In the current study, we orally dosed experimental animals with a common clay mineral, montmorillonite, or whole soils laden with infectious prions, and compared the transmissibility to unbound agent. We found that prions bound to montmorillonite and whole soils remained orally infectious, and, in most cases, increased the oral transmission of disease compared to the unbound agent. The results presented in this study suggest that soil may contribute to environmental spread of TSEs by increasing the transmissibility of small amounts of infectious agent in the environment.

 


 

tse prion soil

 


 


 


 


 

Wednesday, December 16, 2015

 

Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission

 


 

The sources of dust borne prions are unknown but it seems reasonable to assume that faecal, urine, skin, parturient material and saliva-derived prions may contribute to this mobile environmental reservoir of infectivity. This work highlights a possible transmission route for scrapie within the farm environment, and this is likely to be paralleled in CWD which shows strong similarities with scrapie in terms of prion dissemination and disease transmission. The data indicate that the presence of scrapie prions in dust is likely to make the control of these diseases a considerable challenge.

 


 

>>>Particle-associated PrPTSE molecules may migrate from locations of deposition via transport processes affecting soil particles, including entrainment in and movement with air and overland flow. <<<

 

Fate of Prions in Soil: A Review

 

Christen B. Smith, Clarissa J. Booth, and Joel A. Pedersen*

 

Several reports have shown that prions can persist in soil for several years. Significant interest remains in developing methods that could be applied to degrade PrPTSE in naturally contaminated soils. Preliminary research suggests that serine proteases and the microbial consortia in stimulated soils and compost may partially degrade PrPTSE. Transition metal oxides in soil (viz. manganese oxide) may also mediate prion inactivation. Overall, the effect of prion attachment to soil particles on its persistence in the environment is not well understood, and additional study is needed to determine its implications on the environmental transmission of scrapie and CWD.

 


 

P.161: Prion soil binding may explain efficient horizontal CWD transmission

 

Conclusion. Silty clay loam exhibits highly efficient prion binding, inferring a durable environmental reservoir, and an efficient mechanism for indirect horizontal CWD transmission.

 


 

>>>Another alternative would be an absolute prohibition on the movement of deer within the state for any purpose. While this alternative would significantly reduce the potential spread of CWD, it would also have the simultaneous effect of preventing landowners and land managers from implementing popular management strategies involving the movement of deer, and would deprive deer breeders of the ability to engage in the business of buying and selling breeder deer. Therefore, this alternative was rejected because the department determined that it placed an avoidable burden on the regulated community.<<<

 

Wednesday, December 16, 2015

 

Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission

 

Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission

 

Timm Konold1*, Stephen A. C. Hawkins2, Lisa C. Thurston3, Ben C. Maddison4, Kevin C. Gough5, Anthony Duarte1 and Hugh A. Simmons1

 

1 Animal Sciences Unit, Animal and Plant Health Agency Weybridge, Addlestone, UK, 2 Pathology Department, Animal and Plant Health Agency Weybridge, Addlestone, UK, 3 Surveillance and Laboratory Services, Animal and Plant Health Agency Penrith, Penrith, UK, 4 ADAS UK, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK, 5 School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK

 

Classical scrapie is an environmentally transmissible prion disease of sheep and goats. Prions can persist and remain potentially infectious in the environment for many years and thus pose a risk of infecting animals after re-stocking. In vitro studies using serial protein misfolding cyclic amplification (sPMCA) have suggested that objects on a scrapie affected sheep farm could contribute to disease transmission. This in vivo study aimed to determine the role of field furniture (water troughs, feeding troughs, fencing, and other objects that sheep may rub against) used by a scrapie-infected sheep flock as a vector for disease transmission to scrapie-free lambs with the prion protein genotype VRQ/VRQ, which is associated with high susceptibility to classical scrapie. When the field furniture was placed in clean accommodation, sheep became infected when exposed to either a water trough (four out of five) or to objects used for rubbing (four out of seven). This field furniture had been used by the scrapie-infected flock 8 weeks earlier and had previously been shown to harbor scrapie prions by sPMCA. Sheep also became infected (20 out of 23) through exposure to contaminated field furniture placed within pasture not used by scrapie-infected sheep for 40 months, even though swabs from this furniture tested negative by PMCA. This infection rate decreased (1 out of 12) on the same paddock after replacement with clean field furniture. Twelve grazing sheep exposed to field furniture not in contact with scrapie-infected sheep for 18 months remained scrapie free. The findings of this study highlight the role of field furniture used by scrapie-infected sheep to act as a reservoir for disease re-introduction although infectivity declines considerably if the field furniture has not been in contact with scrapie-infected sheep for several months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental contamination.

 

snip...

 

Discussion

 

Classical scrapie is an environmentally transmissible disease because it has been reported in naïve, supposedly previously unexposed sheep placed in pastures formerly occupied by scrapie-infected sheep (4, 19, 20). Although the vector for disease transmission is not known, soil is likely to be an important reservoir for prions (2) where – based on studies in rodents – prions can adhere to minerals as a biologically active form (21) and remain infectious for more than 2 years (22). Similarly, chronic wasting disease (CWD) has re-occurred in mule deer housed in paddocks used by infected deer 2 years earlier, which was assumed to be through foraging and soil consumption (23).

 

Our study suggested that the risk of acquiring scrapie infection was greater through exposure to contaminated wooden, plastic, and metal surfaces via water or food troughs, fencing, and hurdles than through grazing. Drinking from a water trough used by the scrapie flock was sufficient to cause infection in sheep in a clean building. Exposure to fences and other objects used for rubbing also led to infection, which supported the hypothesis that skin may be a vector for disease transmission (9). The risk of these objects to cause infection was further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid tissue after grazing on one of the paddocks, which contained metal hurdles, a metal lamb creep and a water trough in contact with the scrapie flock up to 8 weeks earlier, whereas no infection had been demonstrated previously in sheep grazing on this paddock, when equipped with new fencing and field furniture. When the contaminated furniture and fencing were removed, the infection rate dropped significantly to 8% of 12 sheep, with soil of the paddock as the most likely source of infection caused by shedding of prions from the scrapie-infected sheep in this paddock up to a week earlier.

 

This study also indicated that the level of contamination of field furniture sufficient to cause infection was dependent on two factors: stage of incubation period and time of last use by scrapie-infected sheep. Drinking from a water trough that had been used by scrapie sheep in the predominantly pre-clinical phase did not appear to cause infection, whereas infection was shown in sheep drinking from the water trough used by scrapie sheep in the later stage of the disease. It is possible that contamination occurred through shedding of prions in saliva, which may have contaminated the surface of the water trough and subsequently the water when it was refilled. Contamination appeared to be sufficient to cause infection only if the trough was in contact with sheep that included clinical cases. Indeed, there is an increased risk of bodily fluid infectivity with disease progression in scrapie (24) and CWD (25) based on PrPSc detection by sPMCA. Although ultraviolet light and heat under natural conditions do not inactivate prions (26), furniture in contact with the scrapie flock, which was assumed to be sufficiently contaminated to cause infection, did not act as vector for disease if not used for 18 months, which suggest that the weathering process alone was sufficient to inactivate prions.

 

PrPSc detection by sPMCA is increasingly used as a surrogate for infectivity measurements by bioassay in sheep or mice. In this reported study, however, the levels of PrPSc present in the environment were below the limit of detection of the sPMCA method, yet were still sufficient to cause infection of in-contact animals. In the present study, the outdoor objects were removed from the infected flock 8 weeks prior to sampling and were positive by sPMCA at very low levels (2 out of 37 reactions). As this sPMCA assay also yielded 2 positive reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay could not detect PrPSc on any of the objects above the background of the assay. False positive reactions with sPMCA at a low frequency associated with de novo formation of infectious prions have been reported (27, 28). This is in contrast to our previous study where we demonstrated that outdoor objects that had been in contact with the scrapie-infected flock up to 20 days prior to sampling harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions (12)] and was significantly more positive by the assay compared to analogous samples from the scrapie-free farm. This discrepancy could be due to the use of a different sPMCA substrate between the studies that may alter the efficiency of amplification of the environmental PrPSc. In addition, the present study had a longer timeframe between the objects being in contact with the infected flock and sampling, which may affect the levels of extractable PrPSc. Alternatively, there may be potentially patchy contamination of this furniture with PrPSc, which may have been missed by swabbing. The failure of sPMCA to detect CWD-associated PrP in saliva from clinically affected deer despite confirmation of infectivity in saliva-inoculated transgenic mice was associated with as yet unidentified inhibitors in saliva (29), and it is possible that the sensitivity of sPMCA is affected by other substances in the tested material. In addition, sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more difficult from furniture exposed to weather, which is supported by the observation that PrPSc was detected by sPMCA more frequently in indoor than outdoor furniture (12). A recent experimental study has demonstrated that repeated cycles of drying and wetting of prion-contaminated soil, equivalent to what is expected under natural weathering conditions, could reduce PMCA amplification efficiency and extend the incubation period in hamsters inoculated with soil samples (30). This seems to apply also to this study even though the reduction in infectivity was more dramatic in the sPMCA assays than in the sheep model. Sheep were not kept until clinical end-point, which would have enabled us to compare incubation periods, but the lack of infection in sheep exposed to furniture that had not been in contact with scrapie sheep for a longer time period supports the hypothesis that prion degradation and subsequent loss of infectivity occurs even under natural conditions.

 

In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination. These results suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the detection of environmentally associated scrapie, and suggest that extremely low levels of scrapie contamination are able to cause infection in susceptible sheep genotypes.

 

Keywords: classical scrapie, prion, transmissible spongiform encephalopathy, sheep, field furniture, reservoir, serial protein misfolding cyclic amplification

 


 

Wednesday, December 16, 2015

 

*** Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission ***

 


 

New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication

 

The infectious agents responsible for transmissible spongiform encephalopathy (TSE) are notoriously resistant to most physical and chemical methods used for inactivating pathogens, including heat. It has long been recognized, for example, that boiling is ineffective and that higher temperatures are most efficient when combined with steam under pressure (i.e., autoclaving). As a means of decontamination, dry heat is used only at the extremely high temperatures achieved during incineration, usually in excess of 600°C. It has been assumed, without proof, that incineration totally inactivates the agents of TSE, whether of human or animal origin.

 


 

Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production

 

Histochemical analysis of hamster brains inoculated with the solid residue showed typical spongiform degeneration and vacuolation. Re-inoculation of these brains into a new cohort of hamsters led to onset of clinical scrapie symptoms within 75 days, suggesting that the specific infectivity of the prion protein was not changed during the biodiesel process. The biodiesel reaction cannot be considered a viable prion decontamination method for MBM, although we observed increased survival time of hamsters and reduced infectivity greater than 6 log orders in the solid MBM residue. Furthermore, results from our study compare for the first time prion detection by Western Blot versus an infectivity bioassay for analysis of biodiesel reaction products. We could show that biochemical analysis alone is insufficient for detection of prion infectivity after a biodiesel process.

 


 

Detection of protease-resistant cervid prion protein in water from a CWD-endemic area

 

The data presented here demonstrate that sPMCA can detect low levels of PrPCWD in the environment, corroborate previous biological and experimental data suggesting long term persistence of prions in the environment2,3 and imply that PrPCWD accumulation over time may contribute to transmission of CWD in areas where it has been endemic for decades. This work demonstrates the utility of sPMCA to evaluate other environmental water sources for PrPCWD, including smaller bodies of water such as vernal pools and wallows, where large numbers of cervids congregate and into which prions from infected animals may be shed and concentrated to infectious levels.

 


 

A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing

 

Keywords:Abattoir;bovine spongiform encephalopathy;QRA;scrapie;TSE

 

In this article the development and parameterization of a quantitative assessment is described that estimates the amount of TSE infectivity that is present in a whole animal carcass (bovine spongiform encephalopathy [BSE] for cattle and classical/atypical scrapie for sheep and lambs) and the amounts that subsequently fall to the floor during processing at facilities that handle specified risk material (SRM). BSE in cattle was found to contain the most oral doses, with a mean of 9864 BO ID50s (310, 38840) in a whole carcass compared to a mean of 1851 OO ID50s (600, 4070) and 614 OO ID50s (155, 1509) for a sheep infected with classical and atypical scrapie, respectively. Lambs contained the least infectivity with a mean of 251 OO ID50s (83, 548) for classical scrapie and 1 OO ID50s (0.2, 2) for atypical scrapie. The highest amounts of infectivity falling to the floor and entering the drains from slaughtering a whole carcass at SRM facilities were found to be from cattle infected with BSE at rendering and large incineration facilities with 7.4 BO ID50s (0.1, 29), intermediate plants and small incinerators with a mean of 4.5 BO ID50s (0.1, 18), and collection centers, 3.6 BO ID50s (0.1, 14). The lowest amounts entering drains are from lambs infected with classical and atypical scrapie at intermediate plants and atypical scrapie at collection centers with a mean of 3 × 10−7 OO ID50s (2 × 10−8, 1 × 10−6) per carcass. The results of this model provide key inputs for the model in the companion paper published here.

 


 

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

 

Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3

 


 

>>>Another alternative would be an absolute prohibition on the movement of deer within the state for any purpose. While this alternative would significantly reduce the potential spread of CWD, it would also have the simultaneous effect of preventing landowners and land managers from implementing popular management strategies involving the movement of deer, and would deprive deer breeders of the ability to engage in the business of buying and selling breeder deer. Therefore, this alternative was rejected because the department determined that it placed an avoidable burden on the regulated community.<<<

 

Circulation of prions within dust on a scrapie affected farm

 

Kevin C Gough1, Claire A Baker2, Hugh A Simmons3, Steve A Hawkins3 and Ben C Maddison2*

 

Abstract

 

Prion diseases are fatal neurological disorders that affect humans and animals. Scrapie of sheep/goats and Chronic Wasting Disease (CWD) of deer/elk are contagious prion diseases where environmental reservoirs have a direct link to the transmission of disease. Using protein misfolding cyclic amplification we demonstrate that scrapie PrPSc can be detected within circulating dusts that are present on a farm that is naturally contaminated with sheep scrapie. The presence of infectious scrapie within airborne dusts may represent a possible route of infection and illustrates the difficulties that may be associated with the effective decontamination of such scrapie affected premises.

 

snip...

 

Discussion

 

We present biochemical data illustrating the airborne movement of scrapie containing material within a contaminated farm environment. We were able to detect scrapie PrPSc within extracts from dusts collected over a 70 day period, in the absence of any sheep activity. We were also able to detect scrapie PrPSc within dusts collected within pasture at 30 m but not at 60 m distance away from the scrapie contaminated buildings, suggesting that the chance of contamination of pasture by scrapie contaminated dusts decreases with distance from contaminated farm buildings. PrPSc amplification by sPMCA has been shown to correlate with infectivity and amplified products have been shown to be infectious [14,15]. These experiments illustrate the potential for low dose scrapie infectivity to be present within such samples. We estimate low ng levels of scrapie positive brain equivalent were deposited per m2 over 70 days, in a barn previously occupied by sheep affected with scrapie. This movement of dusts and the accumulation of low levels of scrapie infectivity within this environment may in part explain previous observations where despite stringent pen decontamination regimens healthy lambs still became scrapie infected after apparent exposure from their environment alone [16]. The presence of sPMCA seeding activity and by inference, infectious prions within dusts, and their potential for airborne dissemination is highly novel and may have implications for the spread of scrapie within infected premises. The low level circulation and accumulation of scrapie prion containing dust material within the farm environment will likely impede the efficient decontamination of such scrapie contaminated buildings unless all possible reservoirs of dust are removed. Scrapie containing dusts could possibly infect animals during feeding and drinking, and respiratory and conjunctival routes may also be involved. It has been demonstrated that scrapie can be efficiently transmitted via the nasal route in sheep [17], as is also the case for CWD in both murine models and in white tailed deer [18-20].

 

The sources of dust borne prions are unknown but it seems reasonable to assume that faecal, urine, skin, parturient material and saliva-derived prions may contribute to this mobile environmental reservoir of infectivity. This work highlights a possible transmission route for scrapie within the farm environment, and this is likely to be paralleled in CWD which shows strong similarities with scrapie in terms of prion dissemination and disease transmission. The data indicate that the presence of scrapie prions in dust is likely to make the control of these diseases a considerable challenge.

 


 

***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.

 

P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion

 

Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2

 

1 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWO

 

In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible.

 

***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.

 

PRION 2016 CONFERENCE TOKYO

 


 

Prion protein gene sequence and chronic wasting disease susceptibility in white-tailed deer (Odocoileus virginianus)

 

Adam L Brandt, Amy C Kelly, Michelle L Green, Paul Shelton, Jan Novakofski & Nohra E Mateus-Pinilla To cite this article: Adam L Brandt, Amy C Kelly, Michelle L Green, Paul Shelton, Jan Novakofski & Nohra E Mateus-Pinilla (2015) Prion protein gene sequence and chronic wasting disease susceptibility in white-tailed deer (Odocoileus virginianus), Prion, 9:6, 449-462, DOI: 10.1080/19336896.2015.1115179 To link to this article: http://dx.doi.org/10.1080/19336896.2015.1115179

 

Prion, 9:449–462, 2015 Published with license by Taylor & Francis Group, LLC ISSN: 1933-6896 print / 1933-690X online DOI: 10.1080/19336896.2015.1115179

 

RESEARCH PAPER Prion protein gene sequence and chronic wasting disease susceptibility in white-tailed deer (Odocoileus virginianus) Adam L Brandt1, Amy C Kelly1, Michelle L Green1,2, Paul Shelton3, Jan Novakofski2,*, and Nohra E Mateus-Pinilla1,2 1Illinois Natural History Survey; University of Illinois at Urbana-Champaign; Urbana, IL USA; 2Department of Animal Sciences; University of Illinois at Urbana-Champaign; Urbana, IL USA; 3Illinois Department of Natural Resources; Division of Wildlife Resources; Springfield, IL USA

 

ABSTRACT.

 

The sequence of the prion protein gene (PRNP) affects susceptibility to spongiform encephalopathies, or prion diseases in many species. In white-tailed deer, both coding and noncoding single nucleotide polymorphisms have been identified in this gene that correlate to chronic wasting disease (CWD) susceptibility. Previous studies examined individual nucleotide or amino acid mutations; here we examine all nucleotide polymorphisms and their combined effects on CWD. A 626 bp region of PRNP was examined from 703 free-ranging white-tailed deer. Deer were sampled between 2002 and 2010 by hunter harvest or government culling in Illinois and Wisconsin. Fourteen variable nucleotide positions were identified (4 new and 10 previously reported). We identified 68 diplotypes comprised of 24 predicted haplotypes, with the most common diplotype occurring in 123 individuals. Diplotypes that were found exclusively among positive or negative animals were rare, each occurring in less than 1% of the deer studied. Only one haplotype (C, odds ratio 0.240) and 2 diplotypes (AC and BC, odds ratios of 0.161 and 0.108 respectively) has significant associations with CWD resistance. Each contains mutations (one synonymous nucleotide 555C/T and one nonsynonymous nucleotide 286G/A) at positions reported to be significantly associated with reduced CWD susceptibility. Results suggest that deer populations with higher frequencies of haplotype C or diplotypes AC and BC might have a reduced risk for CWD infection – while populations with lower frequencies may have higher risk for infection. Understanding the genetic basis of CWD has improved our ability to assess herd susceptibility and direct management efforts within CWD infected areas.

 

Adam L Brandt, Amy C Kelly, Michelle L Green, Paul Shelton, Jan Novakofski, and Nohra E Mateus-Pinilla *Correspondence to: Jan Novakofski; Email: jnova@illinois.edu Received September 21, 2015; Revised October 23, 2015; Accepted October 23, 2015. Color versions of one or more of the figures in the article can be found online atwww.tandfonline.com/kprn. This is an Open Access article distributed under the terms of the Creative Commons Attribution-Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. The moral rights of the named author(s) have been asserted.

 

DISCUSSION

 

In this study, we find reduced susceptibility to CWD infection among white-tailed deer with haplotype C (Table 2). We still observed individual deer positive for CWD with this haplotype, demonstrating a reduced susceptibility rather than a complete genetic resistance as is seen with other TSEs (e.g., scrapie36,37). This haplotype had 2 different polymorphisms, 1 synonymous and 1 non-synonymous, both reported to be associated with decreased infection; nt286A (aa96S) and nt555T.10,26,29,30 Other haplotypes have similar mutations at nt286 and nt555 (e.g., haplotypes I, Q, and S); though, within the CWD infection area these haplotypes are not found at all (haplotype Q), occur infrequently (f < 0.01, haplotypes I and S), or are found exclusively among positive deer (haplotype I). A number of other haplotypes have the same mutations at either nt286 or nt555; again most are absent (haplotypes H, V, W and X), infrequent (f < 0.01, haplotypes N and P), or are found abundantly among positive deer (haplotype B) in the CWD infection area (Table 2). Rarity of these haplotypes prevents any meaningful association with changes in susceptibility (Table 2). The effects of mutations at nt286 and nt555 alone or in concert are unclear as other haplotypes with these polymorphisms occur infrequently and with varied susceptibility. An even larger sampling may be necessary to resolve this interaction.

 

Neither haplotypes with aa95H (nt285C) had a significantly reduced susceptibility to CWD (Table 2). Some previous studies reported the occurrence of this mutation among CWD negative deer only, which was interpreted as CWD resistance.26,29 In this study and in the study by Kelly et al.10 the aa95H mutation was found among deer positive for CWD; however, we find in a larger sampling (ND240) the frequency of aa95H to be lower than that found by Kelly et al.10 and not significantly associated with resistance. We cannot preclude the importance of this mutation given that a significant difference in disease susceptibility may be possible with an even larger sample size providing greater statistical power (data not shown).

 

The presence of aa96S has been associated with slowed disease progression, longer life span among captive deer,26,27 and does not appear to affect the rate at which prions are shed from infected individuals.38 Additionally, CWD infected mule deer have been found to excrete pathogenic prions while asymptomatic. 39 This contributes to concerns that wild deer with aa96S may be shedding infectious prions into the environment for longer periods of time than deer lacking the mutation, but are not symptomatic or detectable by immunohistochemical procedures. On the other hand, studies using epidemiological modeling suggest that deer with aa96S under certain conditions may have a selective advantage for CWD resistance over those without.40 With our data, we are unable to make accurate conclusions about detection, longevity, or increased risks of exposure to infectious prions. Nonetheless, our results do corroborate the importance of the polymorphism at G96S in reduced CWD susceptibility (Table 5).26,30

 

Kelly et al.10 found a negative correlation between the number of nucleotide deviations from the PRNP consensus sequence and CWD infection. The database derived consensus sequence reported is the same as the most common haplotype (haplotype A) in this study (Table 1). Haplotype C has 2 deviations from haplotype A; other haplotypes were found containing more deviations but were exceedingly rare (Table 1). These haplotypes (namely haplotypes I, N, Q, S, and X) were largely absent among CWD positive deer (only 2 positive deer were found each with a single copy of haplotype I) and their combined frequency was less than 1%. An increased number of polymorphisms may improve resistance to CWD, but the large sample size of this study (ND703) suggests that haplotypes with more than 2 nucleotide deviations are rare and would not be likely to have an appreciable effect on resistance or susceptibility within the population.

 

Examination of PRNP diplotypes revealed that individuals with at least one copy of haplotype C (specifically AC and BC) were less likely to test positive for CWD (Table 4). Other diplotypes containing at least one copy of haplotype C (mutations at aa96S and nt555T) had a low frequency of occurrence (<1 41="" a="" account="" additional="" address="" age="" all="" always="" analyses="" and="" animals.="" animals="" any="" are="" area.="" area="" as="" association="" at="" attempted="" available="" average="" avoid="" background.29="" basis="" be="" been="" between="" bias.="" but="" by="" c="" cases="" circumstances="" conditions="" confounding="" control="" controlled="" could="" counties="" county="" cwd.="" cwd="" decreasing="" deer43-45="" deer="" design="" determining="" diplotypes="" disease="" distances="" div="" due="" examined="" experimental="" exposed="" factor="" factors="" family="" for="" found="" free="" frequency="" frequent="" from="" genetic="" geographic="" greater="" groups="" haplotype="" harvest.="" have="" herd="" home="" hunter="" i.e.="" ideal="" identified="" illinois="" immunity="" in="" increase="" increasing="" indication="" individually="" infected="" infection="" inheritance="" is="" less="" likelihood="" likely="" locations="" low="" management="" match="" matched-case="" may="" minimize="" more="" multiple="" nature="" negative="" nonetheless="" not="" obtainable="" of="" on="" one="" or="" origin="" originating="" other="" outside="" over="" paired-case="" paired="" perfectly="" play="" population-level="" positive="" possible="" potential="" prnp="" randomly="" range="" ranging="" relatedness="" relationship="" resistance="" restricted="" results="" role="" samples="" sampling="" selected="" sequence="" sex="" significant="" similar="" spurious="" statistical="" status="" strong="" studies="" study="" studying="" suggesting="" susceptibility.="" susceptibility="" than="" that="" the="" therefore="" these="" they="" this="" though="" through="" throughout="" time="" to="" under="" use="" vital="" was="" were="" when="" whitetailed="" with="" without="">
 

The PRNP gene is variable within all species with some mutations affecting susceptibility to TSEs.46-48 Scrapie infection in sheep is the classic example of genetic resistance to a prion disease, where individuals with 2 copies of amino acid sequence V136, R154, Q171 are susceptible to scrapie, and those with 2 copies of the sequence A136, R154, R171 are resistant. 36,37 Changes in the protein coding sequence have been shown to affect the ability of pathogenic prions to convert normal prion proteins31; accordingly, many studies have heavily examined the amino acid variations associated with CWD. Synonymous or silent mutations are often overlooked, but may have a greater effect on protein expression and conformation than expected.49-53Other studies have found significant associations between individual synonymous mutations and CWD susceptibility. 10,28 The specific mechanisms involved between nucleotide variation (specifically synonymous mutations) and CWD are not known, but the rate at which PrPC conformations that are more favorable to PrPSC conversion are produced may be slowed by the presence of certain synonymous mutations.51 Due to the low frequency of haplotypes with similar mutations as haplotype C, we cannot accurately conclude whether or not the specific combination of mutations or any one mutation alone is responsible for reduced CWD susceptibility. Nevertheless, haplotype and diplotype analyses provide more insight in gene-disease association than those restricted to alleles and genotypes54 which are unable to detect additive effects.

 

A solid understanding of the genetics of CWD in white-tailed deer is vital to improve management of CWD on the landscape. Most TSEs are found in domestic or captive animals where management of infected individuals is feasible. For example, scrapie infected flocks can be handled through a process generally involving genetic testing, removal and destruction of infected or suspect animals, followed by decontamination of facilities and equipment.55 Containment of free ranging deer in wild populations potentially infected with CWD and decontamination of the environment is not reasonably possible. The long term effects of CWD are not yet known but it is conceivable that an unmanaged infected population would be gradually extirpated as the disease progresses 56,57 or at least reduced to low densities with high disease prevalence.58,59 Either outcome would have severe ecological effects (e.g., deer play a major role in affecting plant communities60 and as a prey source61,62) as well as negative economic impacts to hunting. Overall disease prevalence has remained at relatively low levels in Illinois compared to Wisconsin. 11 It is important to note that at the time of sampling, CWD had been found in 6 Illinois counties and has since been detected in 14.9 Complete eradication of CWD among free ranging white-tailed deer may not be possible; however, an active containment effort in Illinois appears to have prevented significant increases in prevalence.9,11,12 Further examination of PRNP haplotype and diplotype frequencies across northern Illinois and southern Wisconsin in conjunction with population structure and movement45,63,64 will be useful in identifying localities with greater or reduced susceptibility risk. Effectiveness of CWD containment efforts can be aided through genetic testing and redirecting management resources.

 

snip...

 


 

Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES

 

Title: Comparison of two US sheep scrapie isolates supports identification as separate strains

 

Authors

 

item Moore, Sarah - item Smith, Jodi item West Greenlee, Mary - item Nicholson, Eric item Richt, Juergen item Greenlee, Justin

 

Submitted to: Veterinary Pathology Publication Type: Peer Reviewed Journal Publication Acceptance Date: December 22, 2015 Publication Date: N/A

 

Interpretive Summary: Scrapie is a fatal disease of sheep and goats that causes damaging changes in the brain. The infectious agent is an abnormal protein called a prion that has misfolded from its normal state. Whether or not a sheep will get scrapie is determined primarily by their genetics. Furthermore, different scrapie strains exist that may result in a different expression of disease such as shorter incubation periods, unusual clinical signs, or unique patterns of lesions within the brain. This study evaluated two U.S. scrapie isolates in groups of sheep with varying susceptibilities to scrapie. Our data indicates that there are differences in incubation periods, sheep genotype susceptibilities, and lesion profiles that support designating these scrapie isolates as unique strains. The identification of a new scrapie strain in the United States means that control measures, methods of decontamination, and the potential for transmission to other species may need to be reevaluated. This information is useful to sheep farmers and breeders that are selectively breeding animals with genotypes resistant to the most prevalent strain of scrapie and could impact future regulations for the control of scrapie in the United States. Technical Abstract: Scrapie is a naturally occurring transmissible spongiform encephalopathy (TSE) of sheep and goats. There are different strains of sheep scrapie that are associated with unique molecular, transmission, and phenotype characteristics, but very little is known about the potential presence of scrapie strains within sheep in the US. Scrapie strain and PRNP genotype could both affect susceptibility, potential for transmission, incubation period, and control measures required for eliminating scrapie from a flock. Here we evaluate two US scrapie isolates, No. 13-7 and x124, after intranasal inoculation to compare clinical signs, incubation periods (IP), spongiform lesions, and patterns of PrPSc deposition in sheep with scrapie-susceptible PRNP genotypes (QQ171). After inoculation with x124, susceptibility and IP were associated with valine at codon 136 (V136) of the prion protein: VV136 had short IPs (6.9 months), AV136 sheep were 11.9 months, and AA136 sheep did not develop scrapie. All No.13-7 inoculated sheep developed scrapie with IP’s of 20.1 months for AA136 sheep, 22.8 months for AV136 sheep, and 26.7 months for VV136 sheep. Patterns of immunoreactivity in the brain were influenced by challenge isolate and host genotype. Differences in PrPSc profiles versus isolate were most striking when examining brains from sheep with the VV136 genotype. In summary, intranasal inoculation with isolates x124 and No. 13-7 resulted in differences in IP, sheep genotype susceptibility, and PrPSc profile that support designation as separate strains.

 

Last Modified: 6/6/2016

 


 

PRION 2016 CONFERENCE TOKYO

 

IL-13 Transmission of prions to non human-primates: Implications for human populations

 

Jean-Philippe Deslys, Emmanuel E. Comoy

 

CEW, Institute of Emerging Diseases and Innovative Therapies (iMETI), Division of Prions and Related Diseases (SEPIA), Fontenay-aux-Roses, France

 

Prion diseases 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 prion disease might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, prion diseases, like the other proteinopathies, are reputed to occur spontaneously (atypical animal prion strains, sporadic CJD summing 80 % of human prion cases).

 

Non-human primate models provided the first evidences supporting the transmissibility of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health1, according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the risk of primary (oral) and secondary (transfusional) risk of BSE, and also the zoonotic potential of other animal prion diseases 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' . longer incubation than BSE2. Scrapie, as recently evoked in humanized mice3, is the third potentially zoonotic prion disease (with BSE and L-type BSE4), thus questioning the origin of human sporadic cases. We also observed hidden prions transmitted by blood transfusion in primate which escape to the classical diagnostic methods and extend the field of healthy carriers. We will present an updated panorama of our different long-term transmission studies and discuss the implications on risk assessment of animal prion diseases for human health and of the status of healthy carrier5.

 

1. Chen, C. C. & Wang, Y. H. Estimation of the Exposure of the UK Population to the Bovine Spongiform Encephalopathy Agent through Dietary Intake During the Period 1980 to 1996. PLoS One 9, e94020 (2014).

 

2. Comoy, E. E. et al. Transmission of scrapie prions to primate after an extended silent incubation period. Sci Rep 5, 11573 (2015).

 

3. Cassard, H. et al. Evidence for zoonotic potential of ovine scrapie prions. Nat Commun 5, 5821-5830 (2014).

 

4. Comoy, E. E. et al. Atypical BSE (BASE) transmitted from asymptomatic aging cattle to a primate. PLoS One 3, e3017 (2008).

 

5. Gill O. N. et al. Prevalent abnormal prion protein in human appendixes after bovine spongiform encephalopathy epizootic: large scale survey. BMJ. 347, f5675 (2013).

 

Curriculum Vitae

 

Dr. Deslys co-authored more than one hundred publications in international scientific journals on main aspects of applied prion research (diagnostic, decontamination techniques, risk assessment, and therapeutic approaches in different experimental models) and on underlying pathological mechanisms. He studied the genetic of the first cases of iatrogenic CJD in France. His work has led to several patents including the BSE (Bovine Spongiform Encephalopathy) diagnostic test most widely used worldwide. He also wrote a book on mad cow disease which can be downloaded here for free (http://www.neuroprion.org/pdf_docs/documentation/madcow_deslys.pdf). His research group is Associate Laboratory to National Reference Laboratory for CJD in France and has high security level microbiological installations (NeuroPrion research platform) with different experimental models (mouse, hamster, macaque). The primate model of BSE developed by his group with cynomolgus macaques turned out to mimick remarkably well the human situation and allows to assess the primary (oral) and secondary (transfusional) risks linked to animal and human prions even after very long silent incubation periods. For several years, his interest has extended to the connections between PrP and Alzheimer and the prion mechanisms underlying neurodegenerative diseases. He is coordinating the NeuroPrion international association (initially european network of excellence now open to all prion researchers).

 

- 59-

 

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

 

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

 

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

 

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

 

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

 

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

 

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

 

WS-02

 

Scrapie in swine: A diagnostic challenge

 

Justin J Greenlee1, Robert A Kunkle1, Jodi D Smith1, Heather W. Greenlee2

 

1National Animal Disease Center, US Dept. of Agriculture, Agricultural Research Service, United States; 2Iowa State University College of Veterinary Medicine

 

A naturally occurring prion disease has not been recognized in swine, but the agent of bovine spongiform encephalopathy does transmit to swine by experimental routes. Swine are thought to have a robust species barrier when exposed to the naturally occurring prion diseases of other species, but the susceptibility of swine to the agent of sheep scrapie has not been thoroughly tested.

 

Since swine can be fed rations containing ruminant derived components in the United States and many other countries, we conducted this experiment to test the susceptibility of swine to U.S. scrapie isolates by intracranial and oral inoculation. Scrapie inoculum was a pooled 10% (w/v) homogenate derived from the brains of clinically ill sheep from the 4th passage of a serial passage study of the U.S scrapie agent (No. 13-7) through susceptible sheep that were homozygous ARQ at prion protein residues 136, 154, and 171, respectively. Pigs were inoculated intracranially (n=19) with a single 0.75 ml dose or orally (n=24) with 15 ml repeated on 4 consecutive days. Necropsies were done on a subset of animals at approximately six months post inoculation (PI), at the time the pigs were expected to reach market weight. Remaining pigs were maintained and monitored for clinical signs of TSE until study termination at 80 months PI or when removed due to intercurrent disease (primarily lameness). Brain samples were examined by immunohistochemistry (IHC), western blot (WB), and enzyme-linked immunosorbent assay (ELISA). Brain tissue from a subset of pigs in each inoculation group was used for bioassay in mice expressing porcine PRNP.

 

At six-months PI, no evidence of scrapie infection was noted by any diagnostic method. However, at 51 months of incubation or greater, 5 animals were positive by one or more methods: IHC (n=4), WB (n=3), or ELISA (n=5). Interestingly, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study).

 

Swine inoculated with the agent of scrapie by the intracranial and oral routes do not accumulate abnormal prion protein (PrPSc) to a level detectable by IHC or WB by the time they reach typical market age and weight. However, strong support for the fact that swine are potential hosts for the agent of scrapie comes from positive bioassay from both intracranially and orally inoculated pigs and multiple diagnostic methods demonstrating abnormal prion protein in intracranially inoculated pigs with long incubation times.

 

Curriculum Vitae

 

Dr. Greenlee is Research Veterinary Medical Officer in the Virus and Prion Research Unit at the National Animal Disease Center, US Department of Agriculture, Agricultural Research Service. He applies his specialty in veterinary anatomic pathology to focused research on the intra- and interspecies transmission of prion diseases in livestock and the development of antemortem diagnostic assays for prion diseases. In addition, knockout and transgenic mouse models are used to complement ongoing experiments in livestock species. Dr. Greenlee has publications in a number of topic areas including prion agent decontamination, effects of PRNP genotype on susceptibility to the agent of sheep scrapie, characterization of US scrapie strains, transmission of chronic wasting disease to cervids and cattle, features of H-BSE associated with the E211 K polymorphism, and the development of retinal assessment for antemortem screening for prion diseases in sheep and cattle. Dr. Greenlee obtained his DVM degree and completed the PhD/residency program in Veterinary Pathology at Iowa State University. He is a Diplomate of the American College of Veterinary Pathologists.

 


 

Wednesday, May 25, 2016

 

USDA APHIS National Scrapie TSE Prion Eradication Program April 2016 Monthly Report Prion 2016 Tokyo Update

 


 

Saturday, April 23, 2016

 

Prion 2016 Tokyo Update

 

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

 

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

 


 

Scrapie Sample Submission

 

Submit Samples to Test for Genetic Susceptibility to Scrapie

 

Genetic testing does NOT tell you whether or not a sheep is infected with scrapie

 

Susceptibility to infection in sheep has been shown to vary according to sheep genetics and breed. For classical scrapie in sheep, the codons at positions 136 and 171 in the gene that codes for the amino acids in the prion protein (PrP) have been highly associated with scrapie susceptibility and resistance. At this time, no genes have been identified for goats that confer significant resistance. Therefore, all goats must be assumed to be susceptible.

 

The Genetics of Scrapie Susceptibility Information Sheet

 


 

Scrapie epidemic in a fully PrP-genotyped sheep flock

 

Authors: M. Baylis1, W. Goldmann2, F. Houston1, D. Cairns2, A. Chong2, A. Ross2, A. Smith2, N. Hunter2, A. R. McLean3  VIEW AFFILIATIONS

 

Author for correspondence: Matthew Baylis. Fax +44 1635 577237. e-mail matthew.baylis@bbsrc.ac.uk J. Gen. Virol., November 2002 83: 2907-2914, doi: 10.1099/0022-1317-83-11-2907 Subject: Other Agents Received: 26/03/2002 Accepted: 09/07/2002 Published Online: 01/11/2002

 

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Abstract

 

Fulltext Figs (1) References (17) Cited By (33) Supplementary Material (0) Metrics Related Content

 

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In scrapie-affected sheep flocks, host PrP genotype plays a vital role in determining which sheep will succumb to scrapie and the incubation period. Consequently, within-flock scrapie dynamics is best understood within the context of the genotype profile of the flock. Here we describe a 17 month epidemic of scrapie in a commercially farmed flock of 230 genotyped Texel sheep. At the start of the study, 70% of the sheep were of three genotypes only: ARR/ARQ, ARH/ARQ and ARQ/ARQ. Only 15% of sheep encoded the disease-associated VRQ allele and only a single sheep (0·4%) was of the most susceptible VRQ/VRQ genotype. For susceptible genotypes there was a marked deficit (P<0 13="" 17="" 18="" 2="" 3="" 4="" 55="" 86="" a="" ages="" analysis="" and="" animals="" arq="" as="" associated="" at="" be="" between="" but="" by="" cases="" causes="" cohorts="" confirmed="" death="" defined="" difference="" disease:="" div="" dying="" effect="" ensuing="" farm.="" for="" found="" genotype="" group="" had="" highly="" implying="" in="" known="" later="" median="" middle-="" months="" mortality="" negative="" no="" not="" occurred="" of="" older-age="" older="" on="" or="" positive="" previously.="" prp="" rates="" respectively.="" revealed="" risk="" scrapie="" seven="" sheep.="" sheep="" significant="" six="" some="" submission="" survival="" survivorship="" susceptible="" suspect="" that="" the="" there="" three="" to="" two="" unknown="" vrq="" was="" were="" with="" years="">
 


 


 

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

 


 

Tuesday, July 12, 2016

 

Chronic Wasting Disease CWD, Scrapie, Bovine Spongiform Encephalopathy BSE, TSE, Prion Zoonosis Science History

 

see history of NIH may destroy human brain collection

 


 

Friday, February 05, 2016

 

*** Report of the Committee on Wildlife Diseases FY2015 CWD TSE PRION Detections in Farmed Cervids and Wild ***

 


 

Sunday, July 17, 2016

 

*** CHRONIC WASTING DISEASE CWD TSE PRION GLOBAL REPORT UPDATE JULY 17 2016 ***

 


 

***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.

 

P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion

 

Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2

 

1 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWO

 

In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible.

 

***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.

 

PRION 2016 CONFERENCE TOKYO

 


 

Friday, August 26, 2016

 

Journal Journal of Toxicology and Environmental Health, Part A Volume 79, 2016 - Issue 16-17 Prion Research in Perspective IV CANADA BSE CWD SCRAPIE CJD TSE Prion Disease

 


 

Monday, August 22, 2016

 

CREUTZFELDT JAKOB DISEASE USA 2015 SPORADIC CJD TOTAL FIGURES REACHES HIGHEST ANNUAL COUNT TO DATE AT 239 CONFIRMED CASES

 


 

to be continued...

 

Terry S. Singeltary Sr, Bacliff, Texas USA 77518 flounder9@verizon.net

 

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