Thursday, March 30, 2017

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

Skrantesjuke: VKM report supports the National Veterinary Institute perception management

published 03/29/2017 Scientific Committee for Food Safety (VKM) today presented report on skrantesjuke (Chronic Wasting Disease, CWD) which recommends withdrawal of reindeer herd in northern mountains.

The recommendations in VKMs report on taking out the reindeer herd in Northern Mountains caribou range is in line with the National Veterinary Institute professional judgment. It is a serious action, but are relative to the possible consequences of this the disease, according to the institute. 

Photo: Colourbox 

It was in 2016 that the National Veterinary Institute diagnosed skrantesjuke of caribou in northern mountains and elk in Selbu. This was the first time skrantesjuke were detected outside of North America and South Korea, and the first time it was detected in reindeer. Northern Mountains caribou area includes the municipalities of Aurland, Lærdal, Hemsedal, Hol, Al and Ulvik. Report's recommendation to remove the reindeer herd in Northern Mountains caribou range is in line with the National Veterinary Institute professional judgment. It is a serious action, but are relative to the possible consequences of this the disease. The effect of such a move is uncertain, but the knowledge we have today requires us to adopt a precautionary approach. If the disease in deer is limited to Northern Mountains, the early measures increase the chances of preventing the disease from spreading to new areas and other ungulates. Fast implementation will also be able to reduce the extent of contamination of the environment, which is important with a view to the possible establishment of new caribou herd in northern mountains, says researcher and CWD coordinator Jørn Våge at the National Veterinary Institute. 

He emphasizes that there is considerable uncertainty associated with skrantesjuke in Norway, after last year's detections which also included two cases of moose. Monitoring and knowledge development becomes essential to come, he said. 

Research on skrantesyke (CWD) at the National Veterinary Institute Veterinary 
Institute is already working on several research projects that will provide the necessary knowledge for the best possible management of the disease in Norway. The projects include understanding of the spread of infection, the differences between different varieties of the disease in reindeer and elk, understanding of the genetic prerequisites for infection in Norwegian stocks and development of a CWD test that can be done on live animals. 

In 2016 the monitoring work on skrantesyke intensified, and the National Veterinary Institute tested nationally over 10,000 samples from deer. It is examined reindeer from caribou area and reindeer district bordering the North Mountains, without having been able to demonstrate skrantesjuke there. Since the sample size is too low, one can not yet say whether other areas are free or not. It is likely that we are dealing with two types skrantesjuke to do. One was found on caribou, while the other type was found on elk. Monitoring Efforts skrantesjuke will continue in 2017. The National Veterinary Institute has long experience in combating infectious diseases in both livestock and wildlife, and is ready to assist the administrative authorities with this demanding task in the coming years. Read about Veterinærinstituttes research on CWD Read the report on VKMs sites




CWD in Norway – a state of emergency for the future of cervids (Phase II) 

Opinion of the Panel on Biological Hazards of the Norwegian Scientific Committee for Food Safety

VKM Report 2017:9 11.2 Summary of uncertainties .....................................................................................81 12 Conclusions (with answers to the terms of reference) ................................ 82 13 Data gaps ..................................................................................................... 94 References ........................................................................................................... 95 Appendix I.......................................................................................................... 109 Appendix II ........................................................................................................ 115 Appendix III....................................................................................................... 121 VKM Report 2017:9 7 

Summary 

The Norwegian Food Safety Authority (Mattilsynet, NFSA) and the Norwegian Environment Agency (Miljødirektoratet, NEA) requested the Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) for a scientific opinion on Chronic wasting disease (CWD) in cervids. The project was divided into two phases, and VKM published the scientific opinion from phase I “CWD in Norway” in June 2016. The current report is the result of phase II. 

VKM was asked to provide updated information on food safety, aspects important for transmission of CWD within and between populations and species, and the potential origin of the disease in Norway. Moreover, 

VKM was asked to highlight important risk factors with regard to disease transmission, and how these risk factors might affect choice of management strategy. 

Finally, VKM was asked to highlight relevant management strategies from North America or elsewhere. VKM appointed a working group consisting of one member of the Panel on Microbial Ecology, one member of the Panel on Biological Hazards, and five external experts, as well as VKM`s secretariat to answer the questions from NEA and NFSA. One member of the Panel on Alien Organisms and Trade in Endangered Species (CITES), one member of the Panel on Animal Health and Welfare, as well as one member of the Panel on Biological Hazards commented on the draft report. The Panel on Biological Hazards assessed and approved the final report. 

Background 

Chronic wasting disease (CWD) is a prion disease that affects deer, moose, reindeer, and related species (cervids). Prion diseases are chronic neurodegenerative diseases that occur naturally in humans and ruminants, and are invariably fatal. Some prion diseases, such as classical scrapie in sheep and goats and chronic wasting disease (CWD) in cervids, are contagious, spreading directly between animals or via environmental contamination. In contrast, prion diseases known to affect humans are not known to be contagious. 

Prions are extraordinary agents consisting of misfolded protein aggregates that are remarkably stable and can remain infectious for years in the environment. Prion proteins are present in most animals, but the misfolding makes them very hard to break down. Consequently, misfolded prion proteins accumulate in the brain and eventually in other tissues, causing damage to those tissues. 

Until recently, CWD was only known from North America and South Korea. During a routine marking event in April 2016, a female reindeer (Rangifer tarandus) of the Nordfjella wild reindeer herd in Norway exhibited unusual behaviour, and died shortly afterwards. This unusual death was routinely investigated, and the animal was diagnosed with CWD. This was the first time CWD had been diagnosed outside North America and South Korea and the first case of natural CWD in reindeer. VKM Report 2017:9 8 

In addition, two moose (Alces alces) in Selbu, Norway were diagnosed with CWD in May 2016. Selbu is located approximately 300 km northeast of the Nordfjella mountain range. Currently there is considerable uncertainty regarding the nature of the CWD diagnosed in the two moose. Some of the characteristics of these cases indicate consistency with atypical prion disease, as described in domestic animals, but a final conclusion depends on the results from ongoing investigations. 

Following the diagnosis in reindeer, Norwegian authorities initiated a screening programme in which hunters were requested to collect tissue and the heads of dead cervids during the 2016 hunting season. Animals that had died from causes other than hunting were also tested for CWD. Since March 2016, 4629 samples of moose, 2550 samples of red deer, 627 samples of roe deer, 860 samples of reindeer, 2494 semi-domesticated reindeer, 163 farmed deer and 104 samples of unidentified species were tested for CWD. Two additional cases of CWD were diagnosed in wild reindeer in the Nordfjella population. Together with a clinical, pathological and epidemiological picture consistent with contagious CWD, as described from North America, this indicated that there is an ongoing outbreak of CWD in the wild reindeer population of the northern part of Nordfjella wild reindeer range.
 
Results 

An increase in the distribution and prevalence of CWD will increase exposure of other species, including domestic animals and humans, to this infectious agent. There is currently no evidence indicating transmission of CWD to domestic animals or humans, either by direct contact with cervids, cervid meat, or other products from cervids, or through the environment. VKM continues to support the conclusion from phase I concerning food safety of meat from cervids, that the zoonotic risk of CWD (transmission to humans) is very low. Preliminary results from characterisation of the moose cases and the agent involved indicate that important features deviate significantly from those found in the reindeer and in North American cervids, raising uncertainty with regards to the zoonotic potential. Therefore, based on the data currently available, VKM is not able to reach an evidence-based conclusion regarding the food safety of meat from moose and other cervids infected with this potentially new variant of CWD. 

Whereas direct transmission (animal-to-animal) seems most important in the early phases of a CWD epizootic, the role of indirect transmission (from the environment) increases as the prevalence increases. Once contagious CWD is established, it is very likely that the disease will increase in prevalence within the affected population and spread to contact populations. The rate of increase in prevalence, the resulting impact in a given population, and the efficacy of spread will depend on a range of environmental factors, and the characteristics of the species and population in question. For example, in affected populations of a gregarious species like reindeer, CWD is likely to lead to population decline in the long-term. 

Experiences from North America indicate that prions aggregate in the environment, making eradication of the disease extremely difficult once it has been allowed to develop and become endemic. It is therefore important that efficient measures are implemented at the VKM Report 2017:9 9 earliest opportunity in order to have a realistic chance of eradicating local occurrence of CWD and preventing further spread. 

Contagious CWD found in a confinable population, such as many wild reindeer herds, should be managed by eradication of the host population, fallowing of the area (> 5 years), and restocking from a healthy population. 

The report explains that culling of the Nordfjella reindeer herd is a necessary, immediate response to the current situation. However, as part of an adaptive management strategy, this measure should be under active review and may be revised in the event that new cases of CWD are discovered. 

In contrast, in continuous populations, such as most red deer, moose, and roe deer populations, spatially targeted culling within a defined containment zone should be used to control a CWD outbreak. Confinement of CWD-infected populations should be increased where possible and contact with other populations of cervids restricted, for example by fencing, herding, enhancing natural or man-made obstacles, or decreasing the densities of the relevant cervid populations. 

Potential “hotspots” for disease transmission (supplementary salt-licks, supplementary feeding sites etc.) should be eliminated in areas with CWD as well as the surrounding areas, and should further be considered for other parts of the country. Precautionary measures should be implemented to prevent anthropogenic spread of the disease. 

Finally, increasing the national surveillance of CWD in cervids is essential to ensure that there is a comprehensive basis for future evidence-based management. This is required to ensure that cases and spread of disease are identified as soon as possible, as late discovery will limit the chances for successful eradication of CWD in Norway. 

Key words: VKM, risk assessment, Norwegian Scientific Committee for Food Safety, Norwegian Environment Agency, Chronic Wasting Disease

snip...see full report ;


Short Communication

High prevalence of prion protein genotype associated with resistance to chronic wasting disease in one Alberta woodland caribou population

Yo Ching Cheng, Marco Musiani, Maria Cavedon & Sabine Gilch

Page 00 | Received 31 Jan 2017, Accepted 23 Feb 2017, Accepted author version posted online: 28 Mar 2017


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Translator disclaimer

 Accepted author version

Abstract

Chronic wasting disease (CWD) is a prion disease found in deer, elk and moose in North America and since recently, wild reindeer in Norway. Caribou are at-risk to encounter CWD in areas such as Alberta, Canada, where the disease spreads towards caribou habitats. CWD susceptibility is modulated by species-specific polymorphisms in the prion protein gene (Prnp). We sequenced Prnp of woodland caribou from nine Albertan populations. In one population (Chinchaga) a significantly higher frequency of the 138N allele linked to reduced CWD susceptibility was observed. These data are relevant for developing CWD management strategies including conservation of threatened caribou populations.

Keywords: Chronic wasting disease, caribou, prion protein, prion protein gene polymorphism, genetic resistance, conservation

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As a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.


cwd resistant cervid???
 
***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
 
 
Saturday, May 28, 2016
 
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
 

CHRONIC WASTING DISEASE CWD TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION AKA MAD COW TYPE DISEASE IN CERVID 

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.

TITLE: PATHOLOGICAL FEATURES OF CHRONIC WASTING DISEASE IN REINDEER AND DEMONSTRATION OF HORIZONTAL TRANSMISSION
 
 
*** DECEMBER 2016 CDC EMERGING INFECTIOUS DISEASE JOURNAL CWD HORIZONTAL TRANSMISSION
 
 
*** INFECTIOUS AGENT OF SHEEP SCRAPIE MAY PERSIST IN THE ENVIRONMENT FOR AT LEAST 16 YEARS ***
 
GUDMUNDUR GEORGSSON1, SIGURDUR SIGURDARSON2 AND PAUL BROWN3
 
 
Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission
 
 
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.
 
 

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



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

 
*** Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission
 
 
*** December 2016 CDC Emerging Infectious Disease Journal CWD Horizontal Transmission


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

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.
 
 

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
 


Saturday, May 28, 2016
 
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
 
 
Sunday, December 11, 2016
 
Clay Components in Soil Dictate Environmental Stability and Bioavailability of Cervid Prions in Mice
 
 
Wednesday, December 14, 2016
 
Increased Abundance of M Cells in the Gut Epithelium Dramatically Enhances Oral Prion Disease Susceptibility
 

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 ?

Wednesday, September 7, 2016

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


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. 



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,§ snip...
 
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.
 
 
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)
 
snip...
 
 
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.
 
 
***In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). It is not known how susceptible humans are to CWD but given that the prion can be present in muscle, it is likely that humans have been exposed to the agent via consumption of venison (Sigurdson, 2008). Initial experimental research, however, suggests that human susceptibility to CWD is low and there may be a robust species barrier for CWD transmission to humans (Sigurdson, 2008). It is apparent, though, that CWD is affecting wild and farmed cervid populations in endemic areas with some deer populations decreasing as a result.
 
 
Technical Abstract:
 
***Cattle could be exposed to the agent of chronic wasting disease (CWD) through contact with infected farmed or free-ranging cervids or exposure to contaminated premises. The purpose of this study was to assess the potential for CWD derived from elk to transmit to cattle after intracranial inoculation. Calves (n=14) were inoculated with brain homogenate derived from elk with CWD to determine the potential for transmission and define the clinicopathologic features of disease.
 
Cattle were necropsied if clinical signs occurred or at the termination of experiment (49 months post-inoculation (MPI)).
 
Clinical signs of poor appetite, weight loss, circling, and bruxism occurred in two cattle (14%) at 16 and 17 MPI, respectively.
 
Accumulation of abnormal prion protein (PrP**Sc) in these cattle was confined to the central nervous system with the most prominent immunoreactivity in midbrain, brainstem, and hippocampus with lesser immunoreactivity in the cervical spinal cord.
 
*** The rate of transmission was lower than in cattle inoculated with CWD derived from mule deer (38%) or white-tailed deer (86%).
 
Additional studies are required to fully assess the potential for cattle to develop CWD through a more natural route of exposure, but a low rate of transmission after intracranial inoculation suggests that risk of transmission through other routes is low.
 
***A critical finding here is that if CWD did transmit to exposed cattle, currently used diagnostic techniques would detect and differentiate it from other prion diseases in cattle based on absence of spongiform change, distinct pattern of PrP**Sc deposition, and unique molecular profile.
 
 
Monday, April 04, 2016
 
*** Limited amplification of chronic wasting disease prions in the peripheral tissues of intracerebrally inoculated cattle ***
 
 
Monday, May 02, 2016
 
*** Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo ***
 
 
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.
 
 
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).***
 
 
*** 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.
  
 
*** 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.
 
 
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
 
 
Transmission Studies
 
Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}...TSS
 
resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.
 
snip...
 
 
 
Spongiform Encephalopathy in Captive Wild ZOO BSE INQUIRY
 
 
”The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite it’s subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA veiwed it as a wildlife problem and consequently not their province!” page 26.
 
 
We inoculated cynomolgus macaques with serial dilutions of BSE-infected material. High dose-inoculated animals developed typical clinical disease with all the pathognomonic hallmarks, and incubation periods ranging from 3–8 years. Among low-dosed animals, some developed clinical signs with atypical patterns after extensive incubation periods, exhibiting lesion and biochemical profiles that differed sharply from the typical disease picture. Despite the presence of neurological signs and neuronal lesions, classical lesions of spongiosis and presence of cerebral PrPres were inconstant, or even absent. These observations suggest that low-dose exposure, which would have been the most frequent occurrence during the period of risk, could induce a non-typical pathology that may not be recognized as "prion disease."
 
link url not available, please see PRION 2011 ;
 
 
CHRONIC WASTING DISEASE CWD AND SCRAPIE TSE PRION ZOONOSIS UPDATE
 
*** 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
 
 
Axis Deer and CWD ?
 
Many of the regulations or proposed regulations cover only species known to be susceptible to CWD; however, it is not known whether some farmed exotic cervid species in North America, such as fallow deer (Dama dama), sika deer (Cervus nippon), or axis deer (Axis axis), are susceptible to CWD.
 
 
 


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."


Wednesday, December 21, 2016

TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES 2016 ANNUAL REPORT ARS RESEARCH


Thursday, December 08, 2016

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


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

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

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

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


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

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




TUESDAY, MARCH 28, 2017 

Passage of scrapie to deer results in a new phenotype upon return passage to sheep


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."


***please note, this is what happens with CWD when you let politics take over science, CWD TSE Prion just keeps spreading, spreading, and spreading...

CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats) Farm Update DECEMBER 2011 The CWD infection rate was nearly 80%, the highest ever in a North American captive herd. RECOMMENDATION: That the Board approve the purchase of 80 acres of land for $465,000 for the Statewide Wildlife Habitat Program in Portage County and approve the restrictions on public use of the site.SUMMARY: 


 For Immediate Release Thursday, October 2, 2014 

 Dustin Vande Hoef 515/281-3375 or 515/326-1616 (cell) or Dustin.VandeHoef@IowaAgriculture.gov 

 TEST RESULTS FROM CAPTIVE DEER HERD WITH CHRONIC WASTING DISEASE RELEASED 79.8 percent of the deer tested positive for the disease 

 DES MOINES – The Iowa Department of Agriculture and Land Stewardship today announced that the test results from the depopulation of a quarantined captive deer herd in north-central Iowa showed that 284 of the 356 deer, or 79.8% of the herd, tested positive for Chronic Wasting Disease (CWD). 


*** see history of this CWD blunder here ; 



MONDAY, MARCH 13, 2017

CHRONIC WASTING DISEASE CWD TSE PRION UDATE March 13, 2017


SATURDAY, JANUARY 14, 2017 

CHRONIC WASTING DISEASE CWD TSE PRION GLOBAL UPDATE JANUARY 14, 2017



Terry S. Singeltary Sr.

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