Tuesday, June 20, 2017

Norway Confirms 6th Case of Skrantesjuke CWD TSE Prion Disease

New detection of skrantesjuke

Published 06/20/2017 | Last Modified 06/20/2017

Veterinary Institute has notified the FSA that it for the sixth time is proven skrantesjuke (Chronic Wasting Disease (CWD)) in Norway. The discovery was made on a reindeer goats in North Mountains in New Jersey. The disease is fatal to deer, but has never infected humans, either from animals or meat.

In connection with a mark project under Norwegian Institute for Nature Research (NINA) was sampled reindeer goat and several other reindeer. The actual goat is radiolabeled and still alive, and it will be tracked down and killed shortly. It is located in the region where it has previously been shown skrantesjuke reindeer.

It is decided that the caribou herd in northern mountains should be removed to prevent further spread of skrantesjuke. The objective is to ensure healthy populations of caribou and other ungulates in the future. Food Safety Authority and Environment Agency recently delivered one detailed report to the Ministry of Agriculture -and Food on how this withdrawal can take place .

- It is not surprising that we find more sick animals in this area of ​​Northern Mountains, and it supports the fight against our strategy is correct, says Kristin Ruud Alvseike, senior adviser to the FSA.

New test on the sample stage - Normally, must deer being killed for us to make a diagnosis since it is the brain we take samples. In this case, attempts have been made to use a type of examination of a living, but anesthetized animals says Alvseike.

This test, which is done on lymphoid tissue in the gut, is only at the trial stage and can not be used as a routine test yet. The test can not yet say whether an animal is healthy. Although an animal tests negative on this test, it may still have the disease.

Report you see sick or dead deer Since its inception in 2016 is over 12,000 deer tested skrantesjuke. FSA encourages all who walk in the woods, and who see sick or dead deer to notify the FSA. Symptoms of skrantesjuke is emaciation, disheveled hair, frequent urination and abnormal behavior, such as animals not shun people. This will be helpful to get an overview of how widespread the disease is in Norway.

See also:

More information at Environment Agency: Should take out a GPS-tagged caribou with skrantesjuke

More information at the National Veterinary Institute: New discovery of skrantesjuke on caribou in northern mountains

Contact Media inquiries: Food Safety pressevakt, tel. 469 12910 Other inquiries: Your nearest branch office, tel. 22:40 0:00



Subject: PRION 2017 CONFERENCE ABSTRACT Chronic Wasting Disease in European moose is associated with PrPSc features different from North American CWD

P178 Chronic Wasting Disease in European moose is associated with PrPSc features different from North American CWD

Dr Laura Pirisinu1, Dr Linh Tran2, Dr Gordon Mitchell3, Dr Aru Balachandran3, Dr Thierry Baron4, Dr Cristina Casalone5, Dr Michele Di Bari1, Dr Umberto Agrimi1. Dr Romolo Nonno1, Dr Sylvie Benestad2 

1Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanita, Rome, Italy, 2Norwegian Veterinary Institute, Oslo, Norway, 3Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWD, Ottawa Laboratory Fallowfield, Ottawa, Canada, 4Neurodeqenerative Diseases Unit, ANSES - French Agency for Food, Environmental and Occupational Health & Safety, Lyon, France, 5Istituto Zooprofilattico Sperimentale del Pietnonte, Liguria e Valle d'Aosta, Turin, Italy 

Aims: In 2016, Chronic Wasting Disease (CWD) was detected for the first time in Europe in three wild Norwegian reindeer (Rangifer tarandus tarandus) and in two moose (Alces alces). The biochemical analysis and the immunohistochemical distribution of PrPSc from Norwegian reindeer revealed a pattern similar to North American (NA) isolates1. In this study, we studied the biochemical features of PrPSc from the two CWD cases in Norwegian moose. 

Methods: Western blot (WB) analysis of PK-treated PrPSc (PrPres) from Norwegian moose and reindeer isolates was performed according to the ISS discriminatory WB protocol (used in BSE and scrapie Italian surveillance). PrPres fragments were determined by epitope mapping (SAF84, L42, 9A2, 12B2 mAbs), before and after deglycosylation. CWD isolates from Canadian cervids (wapiti, moose and white tailed deer) and a panel of small ruminant and bovine prion strains circulating in Europe were also analysed. 

Results: WB analysis with different mAbs showed that PrPres from both Norwegian moose samples was different from that usually associated with CWD in cervids. Indeed, their main C-terminal fragment had a MW lower than the other CWD isolates, and could be discriminated by the absence of the 12B2 epitope. Furthermore, while NA CWD PrPSc is composed of a single PrPres fragment, Norwegian moose samples had an additional C-terminal PrPres fragment of ~13 kDa (CTF13). 
Among ovine TSEs, classical scrapie and Nor98 were discriminated from both Norwegian moose isolates, while CH1641 samples had molecular features partially overlapping with the moose, i.e. a low MW PrPres and the presence of CTF13. In contrast, moose PrPSc did not overlap with any bovine PrPSc. Indeed, the MW of moose PrPres was lower than H-BSE and similar to C-BSE and L-BSE PrPres, but the two bovine prions lacked additional PrPres fragments. 

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

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

PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS

please see;

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

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


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

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

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

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

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

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

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

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

snip...


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


snip...see ;

TUESDAY, JUNE 13, 2017

PRION 2017 CONFERENCE ABSTRACT Chronic Wasting Disease in European moose is associated with PrPSc features different from North American CWD


P55 Susceptibility of human prion protein to in vitro conversion by chronic wasting disease prions

Dr Marcelo Barria1, Adriana Libori1, Dr Gordon Mitchell2, Dr Mark Head1 
1National CJD Research & Surveillance Unit, Centre For Clinical Brain Sciences, The University Of Edinburgh, Edinburgh, United Kingdom, 2National and OlE Reference Laboratory for Scrapie and CWD, Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency, Ottawa, Canada

Prion diseases are fatal neurodegenerative conditions occurring in humans as sporadic, genetic and acquired forms. In animals, the majority of prion diseases are acquired. Some animal prion diseases, such as scrapie in sheep are generally considered to be of no or only very low risk to human health. In contrast, bovine spongiform encephalopathy (BSE) is a known zoonotic prion disease strain. The zoonotic status of chronic wasting disease (CWD), a prion disease of cervids, remains poorly quantified. At present CWD has been recognised as a problem in both farmed and wild cervids species in USA, Canada, South Korea, and very recently has been recognised in reindeer in Europe.

 Aim: The aim of this work is to determine whether CWD prions from elk, white tailed deer and caribou (reindeer) are able to convert the human prion protein to the disease-associated form. 

Methods: We have used a cell-free seeded protein misfolding assay, protein misfolding cyclic amplification or PMCA, to test for conversion of the human prion protein by elk, white tailed deer and caribou (reindeer) PrPSc in a single round of amplification. Any misfolded human PrP protein (PrPres) is sensitively detected by Western blot using the 3F4 antibody. 

Results: Amplification reactions seeded with Prnp codon 132 MM elk CWD brain in humanised 129 MM transgenic mouse brain substrate were able to produce human PrPres. However, the heterozygous (132 ML) elk seeds did not result in detectable conversion of the humanised 129 MM PrP substrate, even when similar quantities of PrPres were used to seed the reactions. Low levels of PrPres formation were detected when white tailed deer specimens were tested. The two caribou specimens were both capable of converting the humanised 129 MM PrP substrate efficiently and interestingly, the PRNP codon 129 MV and VV substrates were also readily susceptible to conversion by the caribou seeds. 

Conclusions: We previously reported that elk CWD prions were able to convert human PrPC derived from different sources. Here, we expand on this observation analysing more elk specimens of two different genotypes and analysing the conversion potential of white-tailed deer CWD and caribou (reindeer), the latter which have been experimentally infected with white-tailed deer CWD. Our data confirms that CWD prions are able to convert the human PrPC, at least in vitro, and points to caribou and reindeer as a potential source of zoonotic risk. 

snip...see;

FRIDAY, JUNE 16, 2017

P55 Susceptibility of human prion protein to in vitro conversion by chronic wasting disease prions


Subject: PRION 2017 CONFERENCE ABSTRACT First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress

First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress
 
Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1 

University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen 

This is a progress report of a project which started in 2009. 21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves. 

Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice. 

At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation. 

PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS

 Chronic Wasting Disease CWD TSE Prion to Humans, who makes that final call, when, or, has it already happened?

IF human transmission studies are unethical and will never take place, how much evidence is enough, and how much exposure do we allow, before a call is made. 

HOW many humans do we expose before enough is enough?

How many body bags now are enough, for a very long incubating disease that the body bags will for sure mount later, if something is NOT finally done NOW.

the public must know.

Now, i will tell you all how this will be interpreted by our fine federal friends, and their lobbyist et al from corporate America, and Doctors there from, here is how this will still read, rubber stamped ;

''There is no direct evidence that CWD can transmit to humans, and CWD has never been identified in humans anywhere in the world, including in areas where CWD has been present in animal populations for decades.''

this is absurd, and fake news at it's finest.

what is 'direct evidence', if human transmission is not possible?

there is more than enough evidence to make that call now. 

with that, who will finally make that judgement call, knowing that if cwd transmits to humans, it will look like the most common human tse prion i.e. sporadic cjd?

who makes that final call, when, and how many more humans must die before that decision is made and put in the public domain so we can go on with this and try to implement rules and regulations that might finally turn the tide, or do just let corporate science run rampant? 

or, will they continue to run with the infamous UKBSEnvCJD only theory$

with cwd now being documented to transmit macaque, AND TO PIGS orally (lot of human medicine made from pigs), the price of continuing to play TSE Prion Poker with humans goes up drastically. 

This is criminal negligence now, imo...terry

*** Subject: CWD TRANSMITS TO MACAQUE ORALLY MUSCLE INTAKE ***

Notice to Members Regarding Chronic Wasting Disease (CWD)

Posted on: May 31st, 2017 

To: MNA Members From: Métis Nation of Alberta 

Date: Wednesday, May 31, 2017 

*** Métis Nation of Alberta (MNA) was made aware of a recent Canadian research study examining the transmission of Chronic Wasting Disease. The initial results of the study indicate that macaque monkeys (genetically similar to humans) can be infected with Chronic Wasting Disease (CWD) after eating deer that is infected with CWD. CWD is a prion disease, which are fatal, transmissible diseases characterized by abnormal proteins in the brain and nervous system. To date no research has shown that CWD can be passed on to humans, and no human cases of CWD have ever been identified. However, this new research indicates that it is a possibility. The Deputy Chief Medical Officer of Health has reached out to us to share with our Métis harvesters this important information. For more information you can visit:


and


What the Alberta Government knows: 

CWD is present in southeastern Alberta, with the area slowly spreading westward over time (introduced into Alberta from Saskatchewan) – see map for more information at 


CWD circulates in deer populations, particularly mule deer; it has been found in about 4% of deer tested in 2016; Elk can be infected in areas where CWD has been present in deer for a long period of time; Moose can also be infected, but this would be fairly rare. Necessary Precautions for Harvesters: Hunters and others who handle carcasses follow basic handling precautions (available here 


All deer, moose and elk harvested from CWD mandatory submission wildlife management units (WMUs) be tested for CWD; and A negative result (no CWD detected by the test) must be obtained before any part of an animal is eaten. 

For more information, contact: Amy Quintal Métis Nation of Alberta Métis Harvesting Liaison Tel: (780) 455 – 2200 aquintal@metis.org


Chronic Wasting Disease: CFIA Research Summary 

 Embargoed until May 23, 2017 

(OCR of a scanned original) 

Research Findings 

Chronic Wasting Disease (CWD) is a progressive, fatal disease of the nervous system of cervids including deer, elk, moose, and reindeer that is caused by abnormal proteins called prions. It is known as a transmissible spongiform encephalopathy (TSE). Other TSEs include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, and Creutzfeldt-Jakob disease (CJD) in humans.

A limited number of experimental studies have demonstrated that non-human primates, specifically squirrel monkeys, are susceptible to CWD prions. An ongoing research study has now shown that CWD can also be transmitted to macaques, which are genetically closer to humans. 

The study led by Dr. Stefanie Czub, a scientist at the Canadian Food Inspection Agency (CFIA), and funded by the Alberta Prion Research institute has demonstrated that by orally administering material under experimental conditions from cervids (deer and elk) naturally infected with CWD, the disease can be transmitted to macaques. 

in this project, which began in 2009, 18 macaques were exposed to CWD in a variety of ways: by injecting into the brain, through contact with skin, oral administration, and intravenously (into the bloodstream through veins). So far, results are available from 5 animals. At this point, two animals that were exposed to CWD by direct introduction into the brain, one that was administered infected brain material by oral administration and two that were given infected muscle by oral administration have become infected with CWD. The study is ongoing and testing continues in the remaining animals. The early results will be presented at PRlON 2017, the annual international conference on prion diseases, in Edinburgh, Scotland, May 23 to 26, 2017. 

Potential impacts of the new finding

Since 2003 Canada has a policy that recommends that animals and materials known to be infected with prions be removed from the food chain and from health products. Although no direct evidence of CWD prion transmission to humans has ever been recorded, the policy advocates a precautionary approach to managing CWD and potential human exposure to prions. These initial findings do not change Health Canada’s Health Products and Food Branch (HPFB) position on food and health products. A precautionary approach is still recommended to manage the potential risks of exposure to prions through food and health products. Measures are in place at federal, provincial and territorial levels to reduce human exposure to products potentially contaminated by CWD by preventing known infected animals from entering the marketplace. 

While Federal and P/T government’s animal disease control policies continue to divert known CWD-infected animals away from entering the food and feed supply, research and development of sensitive detection methods including live-animal sampling techniques remain crucial for ensuring an accurate diagnosis. In addition, consistent federal, provincial and territorial communications of appropriate precautionary measures for hunters and indigenous communities are required. 

Next Steps

The CFlA will continue to collaborate with national and international partners to develop and validate new diagnostic techniques. The CFlA will also continue to offer confirmatory testing services and reference laboratory expertise to provincial and territorial partners on demand. 

Currently, CFlA laboratories are leading or collaborating on several research projects to understand the potential for CWD to infect humans. These projects use non‐human primates, genetically modified mice, and cell-free amplification approaches. Given the present findings, CFiA encourages continued research into TSEs. 

The results of this study reinforce the need to redesign the federal program to foster greater adoption of risk mitigation measures for farmed cervids. Federal and provincial government collaboration will continue as new program options are assessed. 

The results of Dr. Czub’s research into CWD will be of interest to scientists, governments, industry and people who consume cervid products. After the presentation at PRION 2017, the research will follow the normal steps of completion, peer review and publication. The Government of Canada will monitor the response to this research and determine whether further review of the science is required. Other studies underway by other researchers may also become public as a result of the presentation of Dr. Czub’s research. 

The Public Health Agency of Canada, Health Canada, CFlA and other Federal partners are working together to assess what policies or programs need further review as well as preparing other communications about the research and health policy and advice to Canadian. 2017/04/28 

===end...UNOFFICIAL...NO URL LINK...TSS===UPDATE, THE ABOVE INTERNAL DOCUMENT HAS NOW BEEN CONFIRMED, but still no link...TSS===

0:30 First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress 

Dr Stefanie Czub University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency Canada 


see science to date that the call should be made NOW, that cwd to humans is possible, and all precautions there fore, should be take will great urgency.

WEDNESDAY, MAY 03, 2017

*** First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques


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).***


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.



*** 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). ***

*** 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). ***

*** 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 ;

http://collections.europarchive.org/tna/20090505194948/http://bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf

you can see more evidence here ;

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

Wednesday, May 24, 2017 

PRION2017 CONFERENCE VIDEO UPDATE 23 – 26 May 2017 Edinburgh UPDATE 1


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

Location: Virus and Prion Research

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

Author item Moore, Sarah item Kunkle, Robert item Kondru, Naveen item Manne, Sireesha item Smith, Jodi item Kanthasamy, Anumantha item West Greenlee, M item Greenlee, Justin

Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 3/15/2017 Publication Date: N/A Citation: N/A Interpretive Summary:

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

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

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

This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge.

CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease.

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


CONFIDENTIAL

EXPERIMENTAL PORCINE SPONGIFORM ENCEPHALOPATHY

While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. ...


we cannot rule out the possibility that unrecognised subclinical spongiform encephalopathy could be present in British pigs though there is no evidence for this: only with parenteral/implantable pharmaceuticals/devices is the theoretical risk to humans of sufficient concern to consider any action.


 Our records show that while some use is made of porcine materials in medicinal products, the only products which would appear to be in a hypothetically ''higher risk'' area are the adrenocorticotrophic hormone for which the source material comes from outside the United Kingdom, namely America China Sweden France and Germany. The products are manufactured by Ferring and Armour. A further product, ''Zenoderm Corium implant'' manufactured by Ethicon, makes use of porcine skin - which is not considered to be a ''high risk'' tissue, but one of its uses is described in the data sheet as ''in dural replacement''. This product is sourced from the United Kingdom.....


 snip...see much more here ;

WEDNESDAY, APRIL 05, 2017

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


P01.47

Quantifying the Species Barrier in Chronic Wasting Disease by a Novel in vitro Conversion Assay

Li, L1; Coulthart, MB2; Balachandran, A3; Chakrabartty, A4; Cashman, NR1 1University of British Columbia, Brain Research Centre, Canada; 2Public Health Agency of Canada, National Microbiology Laboratory, Canada; 3Animal Diseases Research Institute, Canada Food Inspection Agency, National Reference Laboratory for Scrapie and CWD, Canada; 4Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, Canada

Background: Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that can affect North American cervids (deer, elk, and moose). Although the risk of CWD crossing the species barrier and causing human disease is still unknown, however, definite bovine spongiform encephalopathy (BSE) transmission to humans as variant CJD (vCJD), it would seem prudent to limit the exposure of humans to CWD.

Aim: In view of the fact that BSE can be readily transmitted to non-bovid species, it is important to establish the species susceptibility range of CWD.

Methods: In vitro conversion system was performed by incubation of prions with normal brain homogenates as described before, and protease K (PK) resistant PrP was determined by immunoblotting with 6H4 monoclonal prion antibody.

Results: Our results demonstrate that PrPC from cervids (including moose) can be efficiently converted to a protease-resistant form by incubation with elk CWD prions, presumably due to sequence and structural similarities between these species. Interestingly, hamster shows a high conversion ratio by PrPCWD. Moreover, partial denaturation of substrate PrPC can apparently overcome the structural barriers between more distant species.

Conclusions: Our work correctly predicted the transmission of CWD to a wild moose. We find a species barrier for prion protein conversion between cervids and other species, however, this barrier might be overcome if the PrPC substrate has been partially denatured in a cellular environment. Such an environment might also promote CWD transmission to non-cervid species, *** including humans. Acid/GdnHCl-treated brain PrPC was a superior substrate for the in vitro conversion than PrPC treated at physiological pH. This has implications for the process by which the prion protein is converted in disease.

http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf

Wednesday, March 18, 2009 

Noah’s Ark Holding, LLC, Dawson, MN RECALL Elk products contain meat derived from an elk confirmed to have CWD NV, CA, TX, CO, NY, UT, FL, OK RECALLS AND FIELD CORRECTIONS: FOODS CLASS II 

___________________________________ 

PRODUCT 

a) Elk Meat, Elk Tenderloin, Frozen in plastic vacuum packaging. Each package is approximately 2 lbs., and each case is approximately 16 lbs.; Item number 755125, Recall # F-129-9; 

b) Elk Meat, Elk Trim, Frozen; Item number 755155, Recall # F-130-9; 

c) Elk Meat, French Rack, Chilled. Item number 755132, Recall # F-131-9; 

d) Elk Meat, Nude Denver Leg. Item number 755122, Recall # F-132-9; 

e) Elk Meat, New York Strip Steak, Chilled. Item number 755128, Recall # F-133-9; 

f) Elk Meat, Flank Steak Frozen. Item number 755131, Recall # F-134-9; 

CODE 

Elk Meats with production dates of December 29, 30, and 31 

RECALLING FIRM/MANUFACTURER 

Recalling Firm: Sierra Meats, Reno, NV, by telephone on January 29, 2009 and press release on February 9, 2009. 

Manufacturer: Noah’s Ark Holding, LLC, Dawson, MN. Firm initiated recall is ongoing. 

REASON 

Elk products contain meat derived from an elk confirmed to have Chronic Wasting Disease (CWD). 

VOLUME OF PRODUCT IN COMMERCE 

Unknown 

DISTRIBUTION 

NV, CA, TX, CO, NY, UT, FL, OK 

___________________________________ 

http://www.fda.gov/bbs/topics/ENFORCE/2009/ENF01099.html

*** 2016 -2017 UPDATED SCIENCE ON CHRONIC WASTING DISEASE CWD TSE PRION ***


CWD of deer and elk is spreading across North America and cannot be stopped.

The tse prion aka mad cow type disease is not your normal pathogen.

The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.

You cannot cook the TSE prion disease out of meat. you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.

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

The TSE prion agent also survives Simulated Wastewater Treatment Processes.

IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.

You can bury it and it will not go away.

The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.

it’s not your ordinary pathogen you can just cook it out and be done with.

that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.

cwd to humans, consumption, exposure, sub-clinical, iatrogenic, what if ?

i strenuously urge you all to rethink this cutting of funds for research of the TSE Prion disease. 

*** DECEMBER 2016 CDC EMERGING INFECTIOUS DISEASE JOURNAL CWD HORIZONTAL TRANSMISSION 

snip...

Conclusions

Potential sources of infectivity for direct contact animals include urine, feces, and saliva from their CWDwtd-challenged pen-mates, as has been shown for CWD-affected white-tailed deer (6,8,9). Pinpointing the source of infectivity in the indirect contact group is more difficult. Infectious prions can travel at least 30 m in airborne particulate (10), but because the negative control reindeer in the pen adjacent to the indirect contact reindeer did not become positive, a more direct route of transmission is likely in this case. Penning, feeding, and watering protocols were designed to prevent exposure of negative control and indirect contact reindeer to potential infectivity on feed and water buckets, bedding, or fencing (6,11). However, reindeer might have had access to bedding from adjacent pens that had spread into the central alleyway.

During the 5-year course of this study, reindeer were moved between pens several times to maintain an optimal number of animals per pen (Technical Appendix[PDF - 251 KB - 7 pages] Figure 1). Prolonged persistence of prion infectivity in the natural environment has been documented for both CWD (2 years [5]) and scrapie (up to 16 years [12]). In addition, thorough cleaning and disinfection might not be sufficient to remove all infectivity from the environment, leading to persistence of infectivity under experimental housing conditions (13).

In reindeer challenged orally with the agent of CWD, the SS138 genotype (serine/serine at PRNP codon 138) has been associated with susceptibility to disease and the NS138 (asparagine/serine) genotype with resistance (1). In the study we report, disease developed in reindeer with the NS138 genotype after intracranial inoculation, although the extent of lymphoreticular system involvement was significantly lower than in NN138 and SS138 reindeer. The potential association of the NN138 polymorphism with shorter survival times is interesting. However, as with all potential genotype versus phenotype interactions, care should be taken not to over-interpret these results given the small group sizes and the large number of PRNP genotype groups in this study.

Our results demonstrate that reindeer are susceptible to the agent of CWD from white-tailed deer, mule deer, and elk sources after intracranial inoculation. Furthermore, naive reindeer are susceptible to the agent of CWD after direct and indirect exposure to CWD-infected reindeer, suggesting a high potential for horizontal transmission of CWD within and between farmed and free-ranging reindeer (and caribou) populations.

Dr. Moore is a postdoctoral research associate at the National Animal Disease Center, US Department of Agriculture, Ames, Iowa. Her research interests include pathogenesis and pathology of animal diseases with a special interest in neuropathology and prion diseases.


*** INFECTIOUS AGENT OF SHEEP SCRAPIE MAY PERSIST IN THE ENVIRONMENT FOR AT LEAST 16 YEARS *** 

GUDMUNDUR GEORGSSON1, SIGURDUR SIGURDARSON2 AND PAUL BROWN3 

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


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

Submitted to: Emerging Infectious Diseases 

Publication Type: Peer Reviewed Journal 

Publication Acceptance Date: 8/29/2016 

Publication Date: 12/1/2016 

Citation: Moore, S., Kunkle, R., Greenlee, M., Nicholson, E., Richt, J., Hamir, A., Waters, W., Greenlee, J. 2016. Horizontal transmission of chronic wasting disease in reindeer. Emerging Infectious Diseases. 22(12):2142-2145. doi: 10.3201/eid2212.160635.

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.


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. 

***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. 



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 *** 


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

Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3 


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

MONDAY, JUNE 12, 2017

Rethinking Major grain organizations opposition to CFIA's control zone approach to Chronic Wasting CWD TSE Prion Mad Deer Type Disease 2017?


THURSDAY, MARCH 30, 2017 

Norway CWD Skrantesjuke: VKM report supports the National Veterinary Institute perception management 


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


Thursday, April 07, 2016

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


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

Friday, September 30, 2016

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



Scientific Opinion

Chronic wasting disease (CWD) in cervids

Authors

EFSA Panel on Biological Hazards (BIOHAZ),

First published: 18 January 2017Full publication history DOI: 10.2903/j.efsa.2017.4667View/save citation



Tuesday, December 13, 2016

Norway Chronic Wasting Disease CWD TSE Prion disease Skrantesjuke December 2016 Update


Thursday, September 22, 2016

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


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


Wednesday, August 31, 2016

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


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, 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 ;


Tuesday, April 12, 2016

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


Saturday, April 9, 2016

The Norwegian Veterinary Institute (NVI, 2016) has reported a case of prion disease Cervid Spongiform Encephalopathy detected in free ranging wild reindeer (Rangifer tarandus tarandus)

Department for Environment, Food and Rural Affairs


Wednesday, September 28, 2016

Norway sides with OIE, decides to expose millions of consumers to the ATYPICAL BSE SRM TSE Prion aka mad cow type disease


Thursday, January 29, 2015

Atypical H-TYPE BSE Case Confirmed in Norway


WEDNESDAY, MARCH 15, 2017 

In vitro amplification of H-type atypical bovine spongiform encephalopathy by protein misfolding cyclic amplification

"When considering the atypical L-BSE and H-BSE diseases of cattle, they have been assessed in both non-human primate and transgenic mouse bioassays (with mice transgenic for human PRNP) and both model systems indicate that H-BSE and L-BSE may have increased zoonotic potential compare with C-BSE. The detection of all types of BSE is therefore of significant importance."


MONDAY, APRIL 11, 2016

DECLARATION OF EXTRAORDINARY EMERGENCY DUE TO A FOREIGN ANIMAL DISEASE TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION CHRONIC WASTING DISEASE CWD IN THE UNITED STATES AND NORTH AMERICA



Terry S. Singeltary Sr.

posted by Terry S. Singeltary Sr. at 9:23 AM

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