Tuesday, July 21, 2015

Texas CWD Medina County Herd Investigation Update July 16, 2015



TRACE OUT





CWD Medina County Herd Investigation

 

Andy Schwartz, DVM

 

Texas Animal Health Commission

 

Assistant Executive Director for Epidemiology and Laboratories

 

Medina County Affected Herd

 

CWD confirmed in samples submitted from a 2 year old natural born addition in a WTD Breeder Facility

 

Medina County Affected Herd Chronology of Events

 

• Initial report of presumptive positive from TVMDL on Thursday, June 25, 2015

 

• TAHC and TPWD mount joint planning and response effort, ongoing meetings and consultations, based on Texas CWD Response plan revised in 2012 and 2015.

 

• CWD confirmed by NVSL on Tuesday, June 30 - two year old natural born addition to a WTD Breeder Facility in Medina county. TAHC quarantine issued on all facilities under common ownership

 

• TPWD notifies deer breeders through TWIMS – all are non-movement qualified, June 30

 

• Meeting with herd owners, Wednesday, July 1

 

• Multi-Agency CWD Working Group assembled July 6 (TAHC, TPWD, TVMDL, and USDA-APHIS-VS)

 

• TAHC hold orders issued on 177 Tier 1 WTD Facilities and 1 exotic livestock facility on July 9-10

 

Medina County Affected Herd Case Presentation

 

• Laboratory confirmation - obex and medial retropharyngeal lymph nodes

 

• 2 year old buck, born in WTD Breeder Facility in Medina county

 

• No signs consistent with CWD observed

 

• Breeder facility enrolled in TAHC CWD Herd Certificaton Program since 2010 – First Year Status

 

• Two release sites, Medina and Comal counties

 

• Breeder pens surrounded by alleyway, situated on approximately 2000 acre high fenced ranch

 

• CWD susceptible species in high fenced area include released WTD and elk

 

CWD Case Investigation

 

• TAHC is lead in conducting the disease investigation, working closely with TPWD for data on deer movement (TWIMS) and other support.

 

• CWD Management Plan – TPWD and TAHC – revised in 2012 prior to discovery of CWD in free-ranging mule deer in the trans-Pecos area of Texas, and again in April, 2015.

 

• Agencies working closely in a joint response effort

 

CWD Case Investigation

 

• Multi-agency CWD Working Group formed (TAHC, TPWD, TVMDL, and USDA-APHIS-VS)

 

• 5 year investigation span – trace in and trace forward

 

CWD Working Group Priorities

 

• Herd plan for management of trace forward herds with testing of exposed animal

 

• Recommended criteria for movement qualification of herds not in Tier 1

 

• Index Herd testing/management plan

 

• Herd Plans for trace forward herds where exposed animal is not tested

 

• Herd Plan for trace in herds

 

Five Year Span

 

• Trace In: 30 facilities, 126 deer

 

• Trace Forward: 835 deer to 147 facilities

 

• 96 breeders

 

• 46 release sites

 

• 3 DMPs

 

• 2 International

 

Trace In Facilities

 

• Since June 1, 2010 the index herd has received new deer additions from 30 facilities in 30 counties

 

• Index herd also has a nursing facility that took in fawns from 1 facility in 2010, data is not represented on this map

 

see map in link...tss

 

Trace In Facilities

 

• Since June 1, 2010 the index herd has received new deer additions from 30 facilities in 30 counties

 

• Index herd also has a nursing facility that took in fawns from 1 facility in 2010, data is not represented on this map

 

 see map in link...tss

 

 Trace Out Facilities

 

• Counties in which facility owner received deer from index herd since July 1, 2010

 

• 66 Texas sites, 2 Mexico sites

 

• Index herd took in fawns from 1 facility in 2010, data is not represented on this map

 

• All facility owners that have received deer that traced out from the index breeding facility and nursing facility have been sent hold orders

 

Herd Management Factors for Consideration

 

• Per literature, there are two primary sources of exposure to CWD for uninfected deer: Infected deer and contaminated environment

 

• The CWD test positive white-tail deer was a 2 year old, natural born addition - lateral transmission of disease in the index herd is likely

 

• Incubation period for CWD can be as long as five years. Due to the relatively young age of this herd, prior testing of mortalities may not accurately reflect the true disease prevalence.

 

• Significant number of animals moved into and out of the index herd may pose a significant risk to both the captive and wild deer populations in Texas.

 

• Herd prevalence of disease is crucial in assessing risk in all trace forward and trace in herds directly associated with the index herd.

 

Public Outreach and Industry/Expert Input

 

• Joint Agency Press release July 1, 2015

 

• Stakeholder updates via email

 

• Conference calls with Texas deer industry groups on July 3rd, 8th and 10th

 

• Conference call with veterinarians working in deer industry – July 10

 

• Culture, Recreation, and Tourism Committee Hearing July 13

 

• TAHC/TPWD CWD Taskforce meeting July 14

 

• Interviews with television stations and press

 

TAHC CWD Herd Certification Program

 

• Total Enrollment

 

– 189 herds

 

– 18,936 animals

 

• ID requirements

 

• Annual inventory reconciliation and on-site inspection

 

• Test eligible deaths (12 months and older)

 

• Certified Herds: 58

 

– 3 elk

 

– 1 mule deer

 

– 2 reindeer

 

– 1 fallow

 


 

TO DATE, there have been 8 _documented_ cases of CWD in Texas. the state of Texas has floundered to long with CWD TSE prion. if Texas does not act now, and caters to the industry, you will look at another Wisconsin in relations to Chronic Wasting Disease CWD. CWD has been waltzing across Texas from New Mexico for over a decade, long enough to spread this CWD all across the state. Texas thought it was immune to mad cow disease, Texas fell to mad cow disease after a long attempt to cover it up. that is a fact, and everyone around the world knows it. how will Texas handle CWD, probably the same way, Texas will cater to the industry, and thus, cwd tse prion will be trucked to hell and back. I urge every state out there to stay very keen to how TAHC TPWD handle this cwd, or you may be the next state with CWD TSE prion. because the only thing the state of Texas has come to care about, is the state of Texas and their corporate interest$$$

 

IF we look at the trace back and trace forward of the Texas mad cow that did not get away, the 2nd mad cow case that sat up on a shelf for 7 months so the BSE MRR policy can be ratified, and only after an act of congress and letters from scientist all over the world demanding Texas retest that cow they NEW WAS POSTIVE, only until then was that 2nd case of mad cow disease finally confirmed in Weybridge. documents of that blunder are at the bottom. I don’t hold out much hope for any trace forward or trace back of this cwd postive captive cervid.

 

>>> Per literature, there are two primary sources of exposure to CWD for uninfected deer: Infected deer and contaminated environment <<<

 

animal protein in feed for cervid is another source for CWD TSE prion disease. please see ;

 

Oral transmission and early lymphoid tropism of chronic wasting disease PrPres in mule deer fawns (Odocoileus hemionus )

 

Christina J. Sigurdson1, Elizabeth S. Williams2, Michael W. Miller3, Terry R. Spraker1,4, Katherine I. O'Rourke5 and Edward A. Hoover1

 

Department of Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523- 1671, USA1 Department of Veterinary Sciences, University of Wyoming, 1174 Snowy Range Road, University of Wyoming, Laramie, WY 82070, USA 2 Colorado Division of Wildlife, Wildlife Research Center, 317 West Prospect Road, Fort Collins, CO 80526-2097, USA3 Colorado State University Veterinary Diagnostic Laboratory, 300 West Drake Road, Fort Collins, CO 80523-1671, USA4 Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, 337 Bustad Hall, Washington State University, Pullman, WA 99164-7030, USA5

 

Author for correspondence: Edward Hoover.Fax +1 970 491 0523. e-mail ehoover@lamar.colostate.edu

 

Mule deer fawns (Odocoileus hemionus) were inoculated orally with a brain homogenate prepared from mule deer with naturally occurring chronic wasting disease (CWD), a prion-induced transmissible spongiform encephalopathy. Fawns were necropsied and examined for PrP res, the abnormal prion protein isoform, at 10, 42, 53, 77, 78 and 80 days post-inoculation (p.i.) using an immunohistochemistry assay modified to enhance sensitivity. PrPres was detected in alimentary-tract-associated lymphoid tissues (one or more of the following: retropharyngeal lymph node, tonsil, Peyer's patch and ileocaecal lymph node) as early as 42 days p.i. and in all fawns examined thereafter (53 to 80 days p.i.). No PrPres staining was detected in lymphoid tissue of three control fawns receiving a control brain inoculum, nor was PrPres detectable in neural tissue of any fawn. PrPres-specific staining was markedly enhanced by sequential tissue treatment with formic acid, proteinase K and hydrated autoclaving prior to immunohistochemical staining with monoclonal antibody F89/160.1.5. These results indicate that CWD PrP res can be detected in lymphoid tissues draining the alimentary tract within a few weeks after oral exposure to infectious prions and may reflect the initial pathway of CWD infection in deer. The rapid infection of deer fawns following exposure by the most plausible natural route is consistent with the efficient horizontal transmission of CWD in nature and enables accelerated studies of transmission and pathogenesis in the native species.

 

snip...

 

These results indicate that mule deer fawns develop detectable PrP res after oral exposure to an inoculum containing CWD prions. In the earliest post-exposure period, CWD PrPres was traced to the lymphoid tissues draining the oral and intestinal mucosa (i.e. the retropharyngeal lymph nodes, tonsil, ileal Peyer's patches and ileocaecal lymph nodes), which probably received the highest initial exposure to the inoculum. Hadlow et al. (1982) demonstrated scrapie agent in the tonsil, retropharyngeal and mesenteric lymph nodes, ileum and spleen in a 10-month-old naturally infected lamb by mouse bioassay. Eight of nine sheep had infectivity in the retropharyngeal lymph node. He concluded that the tissue distribution suggested primary infection via the gastrointestinal tract. The tissue distribution of PrPres in the early stages of infection in the fawns is strikingly similar to that seen in naturally infected sheep with scrapie. These findings support oral exposure as a natural route of CWD infection in deer and support oral inoculation as a reasonable exposure route for experimental studies of CWD.

 

snip...

 


 

Susceptibility of European Red Deer (Cervus elaphus elaphus) to Alimentary Challenge with Bovine Spongiform Encephalopathy

 

Abstract

 

European red deer (Cervus elaphus elaphus) are susceptible to the agent of bovine spongiform encephalopathy, one of the transmissible spongiform encephalopathies, when challenged intracerebrally but their susceptibility to alimentary challenge, the presumed natural route of transmission, is unknown. To determine this, eighteen deer were challenged via stomach tube with a large dose of the bovine spongiform encephalopathy agent and clinical signs, gross and histological lesions, presence and distribution of abnormal prion protein and the attack rate recorded. Only a single animal developed clinical disease, and this was acute with both neurological and respiratory signs, at 1726 days post challenge although there was significant (27.6%) weight loss in the preceding 141 days. The clinically affected animal had histological lesions of vacuolation in the neuronal perikaryon and neuropil, typical of transmissible spongiform encephalopathies. Abnormal prion protein, the diagnostic marker of transmissible encephalopathies, was primarily restricted to the central and peripheral nervous systems although a very small amount was present in tingible body macrophages in the lymphoid patches of the caecum and colon. Serial protein misfolding cyclical amplification, an in vitro ultra-sensitive diagnostic technique, was positive for neurological tissue from the single clinically diseased deer. All other alimentary challenged deer failed to develop clinical disease and were negative for all other investigations. These findings show that transmission of bovine spongiform encephalopathy to European red deer via the alimentary route is possible but the transmission rate is low. Additionally, when deer carcases are subjected to the same regulations that ruminants in Europe with respect to the removal of specified offal from the human food chain, the zoonotic risk of bovine spongiform encephalopathy, the cause of variant Creutzfeldt-Jakob disease, from consumption of venison is probably very low.

 

snip...

 

Discussion This investigation resulted in the first and only known case, to date, of clinical disease or accumulation of abnormal PrPd in any cervid species due to oral challenge with BSE. The increase in incubation period compared to European red deer challenged with BSE intra-cerebrally (1060 days) [33] compared to oral challenge (1727 days) is approximately 60% and similar to the differences observed in incubation periods for sheep or goats when challenged with TSE agents by these two routes [40,41]. The neurological clinical signs observed could be broadly related to the spongiform encephalopathy and the accumulation of PrPd in that the restlessness, stereotypic head movements and pacing may be due to compromise of the nucleus accumbens [42], found in the striatum, and the laboured breathing due to the lesions in the medulla, where the respiratory centre is located [43]. Alternatively, the laboured and audible mouth breathing may have been due to, or contributed to by, compromise of either of the recurrent laryngeal nerves resulting in some degree of laryngeal paralysis but we were unable to determine this. Apart from the gradual loss of body weight, the speed of onset of clinical signs and progression was very rapid but animal welfare requirements precluded any further longitudinal study of these. The clinical signs described for this animal are broadly similar to those reported for clinical BSE in European red deer challenged via the intracerebral route [33], clinical cases of CWD in deer [44] and clinical cases of BSE in cattle [45].

 

snip...see full text ;

 


 

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

 

======

 

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

 

***However, this recommendation is guidance and not a requirement by law.

 

======

 

31 Jan 2015 at 20:14 GMT

 

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

 

31 Jan 2015 at 20:14 GMT

 


 

Friday, December 14, 2012

 

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

 

snip...

 

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

 

Animals considered at high risk for CWD include:

 

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

 

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

 

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

 

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

 

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

 

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

 

snip...

 

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011). The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE). Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.

 

snip...

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 

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

 

snip...

 


 

Susceptibility of European Red Deer (Cervus elaphus elaphus) to Alimentary Challenge with Bovine Spongiform Encephalopathy

 

Abstract

 

European red deer (Cervus elaphus elaphus) are susceptible to the agent of bovine spongiform encephalopathy, one of the transmissible spongiform encephalopathies, when challenged intracerebrally but their susceptibility to alimentary challenge, the presumed natural route of transmission, is unknown. To determine this, eighteen deer were challenged via stomach tube with a large dose of the bovine spongiform encephalopathy agent and clinical signs, gross and histological lesions, presence and distribution of abnormal prion protein and the attack rate recorded. Only a single animal developed clinical disease, and this was acute with both neurological and respiratory signs, at 1726 days post challenge although there was significant (27.6%) weight loss in the preceding 141 days. The clinically affected animal had histological lesions of vacuolation in the neuronal perikaryon and neuropil, typical of transmissible spongiform encephalopathies. Abnormal prion protein, the diagnostic marker of transmissible encephalopathies, was primarily restricted to the central and peripheral nervous systems although a very small amount was present in tingible body macrophages in the lymphoid patches of the caecum and colon. Serial protein misfolding cyclical amplification, an in vitro ultra-sensitive diagnostic technique, was positive for neurological tissue from the single clinically diseased deer. All other alimentary challenged deer failed to develop clinical disease and were negative for all other investigations. These findings show that transmission of bovine spongiform encephalopathy to European red deer via the alimentary route is possible but the transmission rate is low. Additionally, when deer carcases are subjected to the same regulations that ruminants in Europe with respect to the removal of specified offal from the human food chain, the zoonotic risk of bovine spongiform encephalopathy, the cause of variant Creutzfeldt-Jakob disease, from consumption of venison is probably very low.

 

snip...

 

Discussion This investigation resulted in the first and only known case, to date, of clinical disease or accumulation of abnormal PrPd in any cervid species due to oral challenge with BSE. The increase in incubation period compared to European red deer challenged with BSE intra-cerebrally (1060 days) [33] compared to oral challenge (1727 days) is approximately 60% and similar to the differences observed in incubation periods for sheep or goats when challenged with TSE agents by these two routes [40,41]. The neurological clinical signs observed could be broadly related to the spongiform encephalopathy and the accumulation of PrPd in that the restlessness, stereotypic head movements and pacing may be due to compromise of the nucleus accumbens [42], found in the striatum, and the laboured breathing due to the lesions in the medulla, where the respiratory centre is located [43]. Alternatively, the laboured and audible mouth breathing may have been due to, or contributed to by, compromise of either of the recurrent laryngeal nerves resulting in some degree of laryngeal paralysis but we were unable to determine this. Apart from the gradual loss of body weight, the speed of onset of clinical signs and progression was very rapid but animal welfare requirements precluded any further longitudinal study of these. The clinical signs described for this animal are broadly similar to those reported for clinical BSE in European red deer challenged via the intracerebral route [33], clinical cases of CWD in deer [44] and clinical cases of BSE in cattle [45].

 

snip...see full text ;

 


 

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

 

======

 

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

 

***However, this recommendation is guidance and not a requirement by law.

 

======

 

31 Jan 2015 at 20:14 GMT

 

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

 

31 Jan 2015 at 20:14 GMT

 


 

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.

 

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

 

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

 


 

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

 

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

 


 

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

 

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

 


 

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

 

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

 

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

 


 

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

 

Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3

 


 

Longitudinal Detection of Prion Shedding in Saliva and Urine by CWD-Infected Deer by RT-QuIC

 

Davin M. Henderson1, Nathaniel D. Denkers1, Clare E. Hoover1, Nina Garbino1, Candace K. Mathiason1 and Edward A. Hoover1# + Author Affiliations

 

1Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523 ABSTRACT Chronic Wasting Disease (CWD) is an emergent, rapidly spreading prion disease of cervids. Shedding of infectious prions in saliva and urine is thought to be an important factor in CWD transmission. To help elucidate this issue, we applied an in vitro amplification assay to determine the onset, duration, and magnitude of prion shedding in longitudinally collected saliva and urine samples from CWD-exposed white-tailed deer. We detected prion shedding as early as 3 months after CWD exposure and sustained shedding throughout the disease course. We estimated that a 50% lethal dose (LD50) for cervidized transgenic mice would be contained in 1 ml of infected deer saliva or 10 ml or urine. Given the average course of infection and daily production of these body fluids, an infected deer would shed thousands of prion infectious dosesover the course of CWD infection. The direct and indirect environmental impact of this magnitude of prion shedding for cervid and non-cervid species is surely significant.

 

Importance: Chronic wasting disease (CWD) is an emerging and uniformly fatal prion disease affecting free ranging deer and elk and now recognized in 22 United States and 2 C anadian Provinces. It is unique among prion diseases in that it is transmitted naturally though wild populations. A major hypothesis for CWD's florid spread is that prions are shed in excreta and transmitted via direct or indirect environmental contact. Here we use a rapid in vitro assay to show that infectious doses of CWD prions are in fact shed throughout the multi-year disease course in deer. This finding is an important advance in assessing the risks posed by shed CWD prions to animals as well as humans.

 

FOOTNOTES

 

↵#To whom correspondence should be addressed: Edward A. Hoover, Prion Research Center, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, US Email: edward.hoover@colostate.edu

 


 

Approximately 4,200 fawns, defined as deer under 1 year of age, were sampled from the eradication zone over the last year. The majority of fawns sampled were between the ages of 5 to 9 months, though some were as young as 1 month. Two of the six fawns with CWD detected were 5 to 6 months old. All six of the positive fawns were taken from the core area of the CWD eradication zone where the highest numbers of positive deer have been identified.

 

"This is the first intensive sampling for CWD in fawns anywhere," said Dr. Julie Langenberg, Department of Natural Resources wildlife veterinarian, "and we are trying to learn as much as we can from these data".

 


 

Saturday, February 04, 2012

 

Wisconsin 16 MONTH age limit on testing dead deer Game Farm CWD Testing Protocol Needs To Be Revised

 


 

Articles of Significant Interest Selected from This Issue by the Editors Next Section Prions in the Blood of Infected Hosts: Early and Persistent Prions circulate in the blood of prion-infected hosts, including humans with variant Creutzfeldt-Jakob disease. Determining the parameters of blood-borne prions during the long asymptomatic phase of disease characteristic of all prion diseases has been a long-standing problem in prion biology. Elder et. al (p. 7421–7424) have demonstrated amyloid formation, a biomarker for prions, in the blood of prion-infected rodent and cervid hosts as early as 15 minutes post-mucosal or -intravenous infection. This prionemia persists throughout the disease course, indicating a role for hematogenous prions throughout the preclinical stage of illness.

 


 

***Immediate and Ongoing Detection of Prions in the Blood of Hamsters and Deer following Oral, Nasal, or Blood Inoculations

 

Alan M. Eldera, Davin M. Hendersona, Amy V. Nallsa, Edward A. Hoovera, Anthony E. Kincaidb,c, Jason C. Bartzb and Candace K. Mathiasona aDepartment of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA bMedical Microbiology and Immunology, Creighton University, Omaha, Nebraska, USA cDepartment of Pharmacy Sciences, Creighton University, Omaha, Nebraska, USA S. Perlman, Editor + Author Affiliations

 


 

what about CWD infection rates on some of these game farms ???

 

CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats) FarmUpdate DECEMBER 2011The CWD infection rate was nearly 80%, the highest ever in a North American captive herd. RECOMMENDATION: That the Board approve the purchase of 80acres of land for $465,000 for the Statewide Wildlife Habitat Program inPortage 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). The owners of the quarantined herd have entered into a fence maintenance agreement with the Iowa Department of Agriculture and Land Stewardship,which requires the owners to maintain the 8’ foot perimeter fence around the herd premises for five years after the depopulation was complete and the premises had been cleaned and disinfected CWD is a progressive, fatal, degenerative neurological disease of farmed and free-ranging deer, elk, and moose. There is no known treatment or vaccine for CWD. CWD is not a disease that affects humans.On July 18, 2012, USDA Animal and Plant Health Inspection Service’s (APHIS)National Veterinary Services Lab in Ames, IA confirmed that a male whitetail deer harvested from a hunting preserve in southeast IA was positive for CWD. An investigation revealed that this animal had just been introduced into the hunting preserve from the above-referenced captive deer herd in north-central Iowa.The captive deer herd was immediately quarantined to prevent the spread of CWD. The herd has remained in quarantine until its depopulation on August 25 to 27, 2014.The Iowa Department of Agriculture and Land Stewardship participated in a joint operation to depopulate the infected herd with USDA Veterinary Services, which was the lead agency, and USDA Wildlife Services.Federal indemnity funding became available in 2014. USDA APHIS appraised the captive deer herd of 376 animals at that time, which was before depopulation and testing, at $1,354,250. At that time a herd plan was developed with the owners and officials from USDA and the Iowa Department of Agriculture and Land Stewardship.Once the depopulation was complete and the premises had been cleaned and disinfected, indemnity of $917,100.00 from the USDA has been or will be paid to the owners as compensation for the 356 captive deer depopulated.The Iowa Department of Agriculture and Land Stewardship operates a voluntary CWD program for farms that sell live animals. Currently 145 Iowa farms participate in the voluntary program. The above-referenced captive deer facility left the voluntary CWD program prior to the discovery of the disease as they had stopped selling live animals. All deer harvested in a hunting preserve must be tested for CWD. -30-

 


 

*** see history of this CWD blunder here ;

 


 

On June 5, 2013, DNR conducted a fence inspection, after gaining approval from surrounding landowners, and confirmed that the fenced had beencut or removed in at least four separate locations; that the fence had degraded and was failing to maintain the enclosure around the Quarantined Premises in at least one area; that at least three gates had been opened;and that deer tracks were visible in and around one of the open areas in the sand on both sides of the fence, evidencing movement of deer into the Quarantined Premises.

 


 

CWD, spreading it around...

 

for the game farm industry, and their constituents, to continue to believe that they are _NOT_, and or insinuate that they have _NEVER_ been part of the problem, will only continue to help spread cwd. the game farming industry, from the shooting pens, to the urine mills, the antler mills, the sperm mills, velvet mills, shooting pens, to large ranches, are not the only problem, but it is painfully obvious that they have been part of the problem for decades and decades, just spreading it around, as with transportation and or exportation and or importation of cervids from game farming industry, and have been proven to spread cwd. no one need to look any further than South Korea blunder ;

 

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

 

spreading cwd around...

 

Between 1996 and 2002, chronic wasting disease was diagnosed in 39 herds of farmed elk in Saskatchewan in a single epidemic. All of these herds were depopulated as part of the Canadian Food Inspection Agency’s (CFIA) disease eradication program. Animals, primarily over 12 mo of age, were tested for the presence CWD prions following euthanasia. Twenty-one of the herds were linked through movements of live animals with latent CWD from a single infected source herd in Saskatchewan, 17 through movements of animals from 7 of the secondarily infected herds.

 

***The source herd is believed to have become infected via importation of animals from a game farm in South Dakota where CWD was subsequently diagnosed (7,4). A wide range in herd prevalence of CWD at the time of herd depopulation of these herds was observed. Within-herd transmission was observed on some farms, while the disease remained confined to the introduced animals on other farms.

 


 

spreading cwd around...

 

Friday, May 13, 2011

 

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

 

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

 

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

 

Chronic wasting disease (CWD) has been recognized as an important prion disease in native North America deer and Rocky mountain elks. The disease is a unique member of the transmissible spongiform encephalopathies (TSEs), which naturally affects only a few species. CWD had been limited to USA and Canada until 2000.

 

On 28 December 2000, information from the Canadian government showed that a total of 95 elk had been exported from farms with CWD to Korea. These consisted of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72 elk in 1997, which had been held in pre export quarantine at the “source farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD surveillance program was initiated by the Ministry of Agriculture and Forestry (MAF) in 2001.

 

All elks imported in 1997 were traced back, however elks imported in 1994 were impossible to identify. CWD control measures included stamping out of all animals in the affected farm, and thorough cleaning and disinfection of the premises. In addition, nationwide clinical surveillance of Korean native cervids, and improved measures to ensure reporting of CWD suspect cases were implemented.

 

Total of 9 elks were found to be affected. CWD was designated as a notifiable disease under the Act for Prevention of Livestock Epidemics in 2002.

 

Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and 2005.

 

Since February of 2005, when slaughtered elks were found to be positive, all slaughtered cervid for human consumption at abattoirs were designated as target of the CWD surveillance program. Currently, CWD laboratory testing is only conducted by National Reference Laboratory on CWD, which is the Foreign Animal Disease Division (FADD) of National Veterinary Research and Quarantine Service (NVRQS).

 

In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the human consumption was confirmed as positive. Consequently, all cervid – 54 elks, 41 Sika deer and 5 Albino deer – were culled and one elk was found to be positive. Epidemiological investigations were conducted by Veterinary Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary services.

 

Epidemiologically related farms were found as 3 farms and all cervid at these farms were culled and subjected to CWD diagnosis. Three elks and 5 crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2.

 

All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and confirmed as negative.

 

Further epidemiological investigations showed that these CWD outbreaks were linked to the importation of elks from Canada in 1994 based on circumstantial evidences.

 

In December 2010, one elk was confirmed as positive at Farm 5. Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer – were culled and one Manchurian Sika deer and seven Sika deer were found to be positive. This is the first report of CWD in these sub-species of deer. Epidemiological investigations found that the owner of the Farm 2 in CWD outbreaks in July 2010 had co-owned the Farm 5.

 

In addition, it was newly revealed that one positive elk was introduced from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed (species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as negative.

 


 


 


 


 

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

 

O18

 

Zoonotic Potential of CWD Prions

 

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

 

Chronic wasting disease (CWD) is a widespread and expanding prion disease in free-ranging and captive cervid species in North America. The zoonotic potential of CWD prions is a serious public health concern. Current literature generated with in vitro methods and in vivo animal models (transgenic mice, macaques and squirrel monkeys) reports conflicting results. The susceptibility of human CNS and peripheral organs to CWD prions remains largely unresolved. In our earlier bioassay experiments using several humanized transgenic mouse lines, we detected protease-resistant PrPSc in the spleen of two out of 140 mice that were intracerebrally inoculated with natural CWD isolates, but PrPSc was not detected in the brain of the same mice. Secondary passages with such PrPSc-positive CWD-inoculated humanized mouse spleen tissues led to efficient prion transmission with clear clinical and pathological signs in both humanized and cervidized transgenic mice. Furthermore, a recent bioassay with natural CWD isolates in a new humanized transgenic mouse line led to clinical prion infection in 2 out of 20 mice. These results indicate that the CWD prion has the potential to infect human CNS and peripheral lymphoid tissues and that there might be asymptomatic human carriers of CWD infection.

 

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

 

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

 

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

 

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

 

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

 

The propensity for trans-species prion transmission is related to the structural characteristics of the enciphering and heterologous PrP, but the exact mechanism remains mostly mysterious. Studies of the effects of primary or tertiary prion protein structures on trans-species prion transmission have relied primarily upon animal bioassays, making the influence of prion protein structure vs. host co-factors (e.g. cellular constituents, trafficking, and innate immune interactions) difficult to dissect. As an alternative strategy, we used real-time quakinginduced conversion (RT-QuIC) to investigate trans-species prion conversion.

 

To assess trans-species conversion in the RT-QuIC system, we compared chronic wasting disease (CWD) and bovine spongiform encephalopathy (BSE) prions, as well as feline CWD (fCWD) and feline spongiform encephalopathy (FSE). Each prion was seeded into each host recombinant PrP (full-length rPrP of white-tailed deer, bovine or feline). We demonstrated that fCWD is a more efficient seed for feline rPrP than for white-tailed deer rPrP, which suggests adaptation to the new host.

 

Conversely, FSE maintained sufficient BSE characteristics to more efficiently convert bovine rPrP than feline rPrP. Additionally, human rPrP was competent for conversion by CWD and fCWD. ***This insinuates that, at the level of protein:protein interactions, the barrier preventing transmission of CWD to humans is less robust than previously estimated.

 

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

 

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

 

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

 

Willingham, Erin McNulty, Kelly Anderson, Jeanette Hayes-Klug, Amy Nalls, and Candace Mathiason Colorado State University; Fort Collins, CO USA

 

Chronic wasting disease (CWD) is the transmissible spongiform encephalopathy (TSE), of free-ranging and captive cervids (deer, elk and moose).

 

The presence of infectious prions in the tissues, bodily fluids and environments of clinical and preclinical CWD-infected animals is thought to account for its high transmission efficiency. Recently it has been recognized that mother to offspring transmission may contribute to the facile transmission of some TSEs. Although the mechanism behind maternal transmission is not yet known, the extended asymptomatic TSE carrier phase (lasting years to decades) suggests that it may have implications in the spread of prions.

 

Placental trafficking and/or secretion in milk are 2 means by which maternal prion transmission may occur. In these studies we explore these avenues during early and late infection using a transgenic mouse model expressing cervid prion protein. Na€ıve and CWD-infected dams were bred at both timepoints, and were allowed to bear and raise their offspring. Milk was collected from the dams for prion analysis, and the offspring were observed for TSE disease progression. Terminal tissues harvested from both dams and offspring were analyzed for prions.

 

We have demonstrated that

 

(1) CWDinfected TgCerPRP females successfully breed and bear offspring, and

 

(2) the presence of PrPCWD in reproductive and mammary tissue from CWD-infected dams.

 

We are currently analyzing terminal tissue harvested from offspring born to CWD-infected dams for the detection of PrPCWD and amplification competent prions. These studies will provide insight into the potential mechanisms and biological significance associated with mother to offspring transmission of TSEs.

 

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

 

P.157: Uptake of prions into plants

 

Christopher Johnson1, Christina Carlson1, Matthew Keating1,2, Nicole Gibbs1, Haeyoon Chang1, Jamie Wiepz1, and Joel Pedersen1 1USGS National Wildlife Health Center; Madison, WI USA; 2University of Wisconsin - Madison; Madison, WI USA

 

Soil may preserve chronic wasting disease (CWD) and scrapie infectivity in the environment, making consumption or inhalation of soil particles a plausible mechanism whereby na€ıve animals can be exposed to prions. Plants are known to absorb a variety of substances from soil, including whole proteins, yet the potential for plants to take up abnormal prion protein (PrPTSE) and preserve prion infectivity is not known. In this study, we assessed PrPTSE uptake into roots using laser scanning confocal microscopy with fluorescently tagged PrPTSE and we used serial protein misfolding cyclic amplification (sPMCA) and detect and quantify PrPTSE levels in plant aerial tissues. Fluorescence was identified in the root hairs of the model plant Arabidopsis thaliana, as well as the crop plants alfalfa (Medicago sativa), barley (Hordeum vulgare) and tomato (Solanum lycopersicum) upon exposure to tagged PrPTSE but not a tagged control preparation. Using sPMCA, we found evidence of PrPTSE in aerial tissues of A. thaliana, alfalfa and maize (Zea mays) grown in hydroponic cultures in which only roots were exposed to PrPTSE. Levels of PrPTSE in plant aerial tissues ranged from approximately 4 £ 10 ¡10 to 1 £ 10 ¡9 g PrPTSE g ¡1 plant dry weight or 2 £ 105 to 7 £ 106 intracerebral ID50 units g ¡1 plant dry weight. Both stems and leaves of A. thaliana grown in culture media containing prions are infectious when intracerebrally-injected into mice. ***Our results suggest that prions can be taken up by plants and that contaminated plants may represent a previously unrecognized risk of human, domestic species and wildlife exposure to prions.

 

===========

 

***Our results suggest that prions can be taken up by plants and that contaminated plants may represent a previously unrecognized risk of human, domestic species and wildlife exposure to prions.***

 

SEE ;

 

Friday, May 15, 2015

 

Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions

 

Report

 


 

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P.19: Characterization of chronic wasting disease isolates from freeranging deer (Odocoileus sp) in Alberta and Saskatchewan, Canada

 

Camilo Duque Velasquez1, Chiye Kim1, Nathalie Daude1, Jacques van der Merwe1, Allen Herbst1, Trent Bollinger2, Judd Aiken1, and Debbie McKenzie1 1Centre for Prions and Protein Folding Diseases; University of Alberta; Edmonton, Canada; 2Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon, Canada

 

Chronic wasting disease (CWD) is an emerging prion disease of free ranging and captive species of Cervidae. In North America, CWD is enzootic in some wild cervid populations and can circulate among different deer species. The contagious nature of CWD prions and the variation of cervid PRNP alleles, which influence host susceptibility, can result in the emergence and adaptation of different CWD strains. These strains may impact transmission host range, disease diagnosis, spread dynamics and efficacy of potential vaccines. We are characterizing different CWD agents by biochemical analysis of the PrPCWD conformers, propagation in vitro cell assays1 and by comparing transmission properties and neuropathology in Tg33 (Q95G96) and Tg60 (Q95S96) mice.2 Although Tg60 mice expressing S96- PrPC have been shown resistant to CWD infectivity from various cervid species,2,3

 

***these transgenic mice are susceptible to H95 C CWD, a CWD strain derived from experimental infection of deer expressing H95G96-PrPC. The diversity of strains present in free-ranging mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) from Alberta and Saskatchewan is being determined and will allow us to delineate the properties of CWD agents circulating in CWD enzootic cervid populations of Canada.

 

References

 

1. van der Merwe J, Aiken J, Westaway D, McKenzie D. The standard scrapie cell assay: Development, utility and prospects. Viruses 2015; 7(1):180–198; PMID:25602372; http://dx.doi.org/10.3390/v7010180

 

2. Meade-White K, Race B, Trifilo M, Bossers A, Favara C, Lacasse R, Miller M, Williams E, Oldstone M, Race R, Chesebro B. Resistance to chronic wasting disease in transgenic mice expressing a naturally occurring allelic variant of deer prion protein. J Virol 2007; 81(9):4533–4539; PMID: 17314157; http://dx. doi.org/10.1128/JVI.02762-06

 

3. Race B, Meade-White K, Miller MW, Fox KA, Chesebro B. In vivo comparison of chronic wasting disease infectivity from deer with variation at prion protein residue 96. J Virol 2011; 85(17):9235–9238; PMID: 21697479; http://dx.doi.org/10.1128/JVI.00790-11

 

=========

 

***these transgenic mice are susceptible to H95 C CWD, a CWD strain derived from experimental infection of deer expressing H95G96-PrPC.

 

==========

 

P.136: Mother to offspring transmission of CWD—Detection in fawn tissues using the QuIC assay

 

Amy Nalls, Erin McNulty, Clare Hoover, Jeanette Hayes-Klug, Kelly Anderson, Edward Hoover, and Candace Mathiason Colorado State University; Fort Collins, CO USA

 

To investigate the role mother to offspring transmission plays in chronic wasting disease (CWD), we have employed a small, polyestrous breeding, indoor maintainable cervid model, the Reeves’ muntjac deer. Muntjac doe were inoculated with CWD and tested positive by lymphoid biopsy at 4 months post inoculation. From these CWD-infected doe, we obtained 3 viable fawns. These fawns tested IHC-positive for CWD by lymphoid biopsy as early as 40 d post birth, and all have been euthanized due to clinical disease at 31, 34 and 59 months post birth. The QuIC assay demonstrates sensitivity and specificity in the detection of conversion competent prions in peripheral IHC-positive tissues including tonsil, mandibular, partotid, retropharyngeal, and prescapular lymph nodes, adrenal gland, spleen and liver. In summary, using the muntjac deer model, we have demonstrated CWD clinical disease in offspring born to CWD-infected doe and found that the QuIC assay is an effective tool in the detection of prions in peripheral tissues. ***Our findings demonstrate that transmission of prions from mother to offspring can occur, and may be underestimated for all prion diseases.

 

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

 

***Our findings demonstrate that transmission of prions from mother to offspring can occur, and may be underestimated for all prion diseases.

 

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

 


 

98 | Veterinary Record | January 24, 2015

 

EDITORIAL

 

Scrapie: a particularly persistent pathogen

 

Cristina Acín

 

Resistant prions in the environment have been the sword of Damocles for scrapie control and eradication. Attempts to establish which physical and chemical agents could be applied to inactivate or moderate scrapie infectivity were initiated in the 1960s and 1970s,with the first study of this type focusing on the effect of heat treatment in reducing prion infectivity (Hunter and Millson 1964). Nowadays, most of the chemical procedures that aim to inactivate the prion protein are based on the method developed by Kimberlin and collaborators (1983). This procedure consists of treatment with 20,000 parts per million free chlorine solution, for a minimum of one hour, of all surfaces that need to be sterilised (in laboratories, lambing pens, slaughterhouses, and so on). Despite this, veterinarians and farmers may still ask a range of questions, such as ‘Is there an official procedure published somewhere?’ and ‘Is there an international organisation which recommends and defines the exact method of scrapie decontamination that must be applied?’

 

From a European perspective, it is difficult to find a treatment that could be applied, especially in relation to the disinfection of surfaces in lambing pens of affected flocks. A 999/2001 EU regulation on controlling spongiform encephalopathies (European Parliament and Council 2001) did not specify a particular decontamination measure to be used when an outbreak of scrapie is diagnosed. There is only a brief recommendation in Annex VII concerning the control and eradication of transmissible spongiform encephalopathies (TSE s).

 

Chapter B of the regulation explains the measures that must be applied if new caprine animals are to be introduced to a holding where a scrapie outbreak has previously been diagnosed. In that case, the statement indicates that caprine animals can be introduced ‘provided that a cleaning and disinfection of all animal housing on the premises has been carried out following destocking’.

 

Issues around cleaning and disinfection are common in prion prevention recommendations, but relevant authorities, veterinarians and farmers may have difficulties in finding the specific protocol which applies. The European Food and Safety Authority (EFSA ) published a detailed report about the efficacy of certain biocides, such as sodium hydroxide, sodium hypochlorite, guanidine and even a formulation of copper or iron metal ions in combination with hydrogen peroxide, against prions (EFSA 2009). The report was based on scientific evidence (Fichet and others 2004, Lemmer and others 2004, Gao and others 2006, Solassol and others 2006) but unfortunately the decontamination measures were not assessed under outbreak conditions.

 

The EFSA Panel on Biological Hazards recently published its conclusions on the scrapie situation in the EU after 10 years of monitoring and control of the disease in sheep and goats (EFSA 2014), and one of the most interesting findings was the Icelandic experience regarding the effect of disinfection in scrapie control. The Icelandic plan consisted of: culling scrapie-affected sheep or the whole flock in newly diagnosed outbreaks; deep cleaning and disinfection of stables, sheds, barns and equipment with high pressure washing followed by cleaning with 500 parts per million of hypochlorite; drying and treatment with 300 ppm of iodophor; and restocking was not permitted for at least two years. Even when all of these measures were implemented, scrapie recurred on several farms, indicating that the infectious agent survived for years in the environment, even as many as 16 years after restocking (Georgsson and others 2006).

 

In the rest of the countries considered in the EFSA (2014) report, recommendations for disinfection measures were not specifically defined at the government level. In the report, the only recommendation that is made for sheep is repopulation with sheep with scrapie-resistant genotypes. This reduces the risk of scrapie recurrence but it is difficult to know its effect on the infection.

 

Until the EFSA was established (in May 2003), scientific opinions about TSE s were provided by the Scientific Steering Committee (SSC) of the EC, whose advice regarding inactivation procedures focused on treating animal waste at high temperatures (150°C for three hours) and high pressure alkaline hydrolysis (SSC 2003). At the same time, the TSE Risk Management Subgroup of the Advisory Committee on Dangerous Pathogens (ACDP) in the UK published guidance on safe working and the prevention of TSE infection. Annex C of the ACDP report established that sodium hypochlorite was considered to be effective, but only if 20,000 ppm of available chlorine was present for at least one hour, which has practical limitations such as the release of chlorine gas, corrosion, incompatibility with formaldehyde, alcohols and acids, rapid inactivation of its active chemicals and the stability of dilutions (ACDP 2009).

 

In an international context, the World Organisation for Animal Health (OIE) does not recommend a specific disinfection protocol for prion agents in its Terrestrial Code or Manual. Chapter 4.13 of the Terrestrial Code, General recommendations on disinfection and disinsection (OIE 2014), focuses on foot-and-mouth disease virus, mycobacteria and Bacillus anthracis, but not on prion disinfection. Nevertheless, the last update published by the OIE on bovine spongiform encephalopathy (OIE 2012) indicates that few effective decontamination techniques are available to inactivate the agent on surfaces, and recommends the removal of all organic material and the use of sodium hydroxide, or a sodium hypochlorite solution containing 2 per cent available chlorine, for more than one hour at 20ºC.

 

The World Health Organization outlines guidelines for the control of TSE s, and also emphasises the importance of mechanically cleaning surfaces before disinfection with sodium hydroxide or sodium hypochlorite for one hour (WHO 1999).

 

Finally, the relevant agencies in both Canada and the USA suggest that the best treatments for surfaces potentially contaminated with prions are sodium hydroxide or sodium hypochlorite at 20,000 ppm. This is a 2 per cent solution, while most commercial household bleaches contain 5.25 per cent sodium hypochlorite. It is therefore recommended to dilute one part 5.25 per cent bleach with 1.5 parts water (CDC 2009, Canadian Food Inspection Agency 2013).

 

So what should we do about disinfection against prions? First, it is suggested that a single protocol be created by international authorities to homogenise inactivation procedures and enable their application in all scrapie-affected countries. Sodium hypochlorite with 20,000 ppm of available chlorine seems to be the procedure used in most countries, as noted in a paper summarised on p 99 of this issue of Veterinary Record (Hawkins and others 2015). But are we totally sure of its effectiveness as a preventive measure in a scrapie outbreak? Would an in-depth study of the recurrence of scrapie disease be needed?

 

What we can conclude is that, if we want to fight prion diseases, and specifically classical scrapie, we must focus on the accuracy of diagnosis, monitoring and surveillance; appropriate animal identification and control of movements; and, in the end, have homogeneous and suitable protocols to decontaminate and disinfect lambing barns, sheds and equipment available to veterinarians and farmers. Finally, further investigations into the resistance of prion proteins in the diversity of environmental surfaces are required.

 

References

 

snip...

 

98 | Veterinary Record | January 24, 2015

 


 

Persistence of ovine scrapie infectivity in a farm environment following cleaning and decontamination

 

Steve A. C. Hawkins, MIBiol, Pathology Department1, Hugh A. Simmons, BVSc MRCVS, MBA, MA Animal Services Unit1, Kevin C. Gough, BSc, PhD2 and Ben C. Maddison, BSc, PhD3 + Author Affiliations

 

1Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK 2School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK 3ADAS UK, School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK E-mail for correspondence: ben.maddison@adas.co.uk Abstract Scrapie of sheep/goats and chronic wasting disease of deer/elk are contagious prion diseases where environmental reservoirs are directly implicated in the transmission of disease. In this study, the effectiveness of recommended scrapie farm decontamination regimens was evaluated by a sheep bioassay using buildings naturally contaminated with scrapie. Pens within a farm building were treated with either 20,000 parts per million free chorine solution for one hour or were treated with the same but were followed by painting and full re-galvanisation or replacement of metalwork within the pen. Scrapie susceptible lambs of the PRNP genotype VRQ/VRQ were reared within these pens and their scrapie status was monitored by recto-anal mucosa-associated lymphoid tissue. All animals became infected over an 18-month period, even in the pen that had been subject to the most stringent decontamination process. These data suggest that recommended current guidelines for the decontamination of farm buildings following outbreaks of scrapie do little to reduce the titre of infectious scrapie material and that environmental recontamination could also be an issue associated with these premises.

 

SNIP...

 

Discussion

 

Thorough pressure washing of a pen had no effect on the amount of bioavailable scrapie infectivity (pen B). The routine removal of prions from surfaces within a laboratory setting is treatment for a minimum of one hour with 20,000 ppm free chlorine, a method originally based on the use of brain macerates from infected rodents to evaluate the effectiveness of decontamination (Kimberlin and others 1983). Further studies have also investigated the effectiveness of hypochlorite disinfection of metal surfaces to simulate the decontamination of surgical devices within a hospital setting. Such treatments with hypochlorite solution were able to reduce infectivity by 5.5 logs to lower than the sensitivity of the bioassay used (Lemmer and others 2004). Analogous treatment of the pen surfaces did not effectively remove the levels of scrapie infectivity over that of the control pens, indicating that this method of decontamination is not effective within a farm setting. This may be due to the high level of biological matrix that is present upon surfaces within the farm environment, which may reduce the amount of free chlorine available to inactivate any infectious prion. Remarkably 1/5 sheep introduced into pen D had also became scrapie positive within nine months, with all animals in this pen being RAMALT positive by 18 months of age. Pen D was no further away from the control pen (pen A) than any of the other pens within this barn. Localised hot spots of infectivity may be present within scrapie-contaminated environments, but it is unlikely that pen D area had an amount of scrapie contamination that was significantly different than the other areas within this building. Similarly, there were no differences in how the biosecurity of pen D was maintained, or how this pen was ventilated compared with the other pens. This observation, perhaps, indicates the slower kinetics of disease uptake within this pen and is consistent with a more thorough prion removal and recontamination. These observations may also account for the presence of inadvertent scrapie cases within other studies, where despite stringent biosecurity, control animals have become scrapie positive during challenge studies using barns that also housed scrapie-affected animals (Ryder and others 2009). The bioassay data indicate that the exposure of the sheep to a farm environment after decontamination efforts thought to be effective in removing scrapie is sufficient for the animals to become infected with scrapie. The main exposure routes within this scenario are likely to be via the oral route, during feeding and drinking, and respiratory and conjunctival routes. It has been demonstrated that scrapie infectivity can be efficiently transmitted via the nasal route in sheep (Hamir and others 2008), as is the case for CWD in both murine models and in white-tailed deer (Denkers and others 2010, 2013). Recently, it has also been demonstrated that CWD prions presented as dust when bound to the soil mineral montmorillonite can be infectious via the nasal route (Nichols and others 2013). When considering pens C and D, the actual source of the infectious agent in the pens is not known, it is possible that biologically relevant levels of prion survive on surfaces during the decontamination regimen (pen C). With the use of galvanising and painting (pen D) covering and sealing the surface of the pen, it is possible that scrapie material recontaminated the pens by the movement of infectious prions contained within dusts originating from other parts of the barn that were not decontaminated or from other areas of the farm.

 

Given that scrapie prions are widespread on the surfaces of affected farms (Maddison and others 2010a), irrespective of the source of the infectious prions in the pens, this study clearly highlights the difficulties that are faced with the effective removal of environmentally associated scrapie infectivity. This is likely to be paralleled in CWD which shows strong similarities to scrapie in terms of both the dissemination of prions into the environment and the facile mode of disease transmission. These data further contribute to the understanding that prion diseases can be highly transmissible between susceptible individuals not just by direct contact but through highly stable environmental reservoirs that are refractory to decontamination.

 

The presence of these environmentally associated prions in farm buildings make the control of these diseases a considerable challenge, especially in animal species such as goats where there is lack of genetic resistance to scrapie and, therefore, no scope to re-stock farms with animals that are resistant to scrapie.

 

Scrapie Sheep Goats Transmissible spongiform encephalopathies (TSE) Accepted October 12, 2014. Published Online First 31 October 2014

 


 

Monday, November 3, 2014

 

Persistence of ovine scrapie infectivity in a farm environment following cleaning and decontamination

 


 

PPo3-22:

 

Detection of Environmentally Associated PrPSc on a Farm with Endemic Scrapie

 

Ben C. Maddison,1 Claire A. Baker,1 Helen C. Rees,1 Linda A. Terry,2 Leigh Thorne,2 Susan J. Belworthy2 and Kevin C. Gough3 1ADAS-UK LTD; Department of Biology; University of Leicester; Leicester, UK; 2Veterinary Laboratories Agency; Surry, KT UK; 3Department of Veterinary Medicine and Science; University of Nottingham; Sutton Bonington, Loughborough UK

 

Key words: scrapie, evironmental persistence, sPMCA

 

Ovine scrapie shows considerable horizontal transmission, yet the routes of transmission and specifically the role of fomites in transmission remain poorly defined. Here we present biochemical data demonstrating that on a scrapie-affected sheep farm, scrapie prion contamination is widespread. It was anticipated at the outset that if prions contaminate the environment that they would be there at extremely low levels, as such the most sensitive method available for the detection of PrPSc, serial Protein Misfolding Cyclic Amplification (sPMCA), was used in this study. We investigated the distribution of environmental scrapie prions by applying ovine sPMCA to samples taken from a range of surfaces that were accessible to animals and could be collected by use of a wetted foam swab. Prion was amplified by sPMCA from a number of these environmental swab samples including those taken from metal, plastic and wooden surfaces, both in the indoor and outdoor environment. At the time of sampling there had been no sheep contact with these areas for at least 20 days prior to sampling indicating that prions persist for at least this duration in the environment. These data implicate inanimate objects as environmental reservoirs of prion infectivity which are likely to contribute to disease transmission.

 


 

Friday, May 22, 2015

 

Chronic Wasting Disease and Program Updates - 2014 NEUSAHA Annual Meeting 12-14 May 2014

 


 

U.S. Attorneys » Eastern District of Missouri » News Justice News Department of Justice U.S. Attorney’s Office Eastern District of Missouri

 

--------------------------------------------------------------------------------

 

FOR IMMEDIATE RELEASE

 

Wednesday, June 10, 2015

 

Missouri Resident Charged with Federal Lacey Act Violations St Louis, MO – CHARLES "SAM" JAMES, Columbia, Missouri, was charged in a one-count federal indictment for violations of the Lacey Act for engaging in conduct that involved the sale of white-tailed deer transported in violation of Missouri and Florida law.

 

According to the indictment, in October 2013, Charles “Sam” James, co-owner of Timber Hollow Whitetails, transported eleven live white-tailed deer in interstate commerce in violation of state and federal laws from Missouri to a white-tailed deer farm in Florida. The transportation of these animals took place after a Florida state law took effect banning the importation of captive white-tailed deer. The defendant allegedly transported the deer from Timber Hollow Whitetails near Mexico, Missouri, in a rented utility box trailer, to a deer farm near Laurel Hills, Florida.

 

Federal law makes it unlawful to transport live white-tailed deer out of the State of Missouri or into the State of Florida without proper documentation of the animals and without required animal health records. These health records include certifying that captive-bred animals are free from diseases like chronic wasting disease, tuberculosis and brucellosis.

 

Chronic wasting disease is the chief threat to wild deer and elk populations in North America. The disease, which ultimately ends in the death of infected animals, is a transmissible neurological disease that produces small lesions in the brain of deer and elk and is characterized by loss of body condition and behavioral abnormalities.

 

If convicted, this charge carries a maximum penalty of five years in prison, a $250,000 fine or both. In determining the actual sentences, a judge is required to consider the U.S. Sentencing Guidelines, which provide recommended sentencing ranges.

 

This case was investigated by agents from the U.S. Fish and Wildlife Service, the Missouri Department of Conservation and the Florida Fish and Wildlife Conservation Commission. Assistant United States Attorney Dianna Collins is handling the case for the U.S. Attorney’s Office.

 

As is always the case, charges set forth in an indictment are merely accusations and do not constitute proof of guilt. Every defendant is presumed to be innocent unless and until proven guilty.

 

 USAO - Missouri, Eastern District Updated June 10, 2015

 


 

Sam James, president of the Missouri Deer Association, said their association is determined to see this process through to the end. “Our state legislators already passed the bills overwhelmingly because they get it. They looked at the science and facts and compared them with the negative media hype from the conservation special interest groups. It didn’t add up and we are grateful for their courage to stand for what’s right.”

 

The Missouri Department of Conservation has publically stated that the deer farmers are a probable catalyst for the spread of Chronic Wasting Disease (CWD) and therefore opposed the passage of the bills.

 


 

Tuesday, June 16, 2015

 

Missouri MDC changes deer hunting regs to help slow CWD

 


 

Thursday, May 15, 2014

 

Missouri Stripping MDC regulatory authority of deer farms SB 506 HOW THEY VOTED Singeltary letter to Governor Nixon

 


 

MDC reports two new cases of CWD found in Adair and Macon counties

 

Published on: Jan. 26, 2015

 

Posted by Joe Jerek

 

JEFFERSON CITY, Mo. -- The Missouri Department of Conservation (MDC) reports that two new cases of chronic wasting disease (CWD) have recently been found in north-central Missouri. One was found in an adult buck harvested by a hunter in Macon County and the other in an adult doe harvested by a hunter in Adair County. These two new cases bring the total of Missouri free-ranging deer that have tested positive for CWD to five for this hunting season and 15 overall. The total cases of CWD in Missouri captive and free-ranging deer now stands at 26.

 

CWD was first discovered in Missouri in 2010 at a private hunting preserve in Linn County. All cases of CWD in Missouri have been limited to Macon, Linn, and Adair counties, which are part of MDC's six-county CWD Containment Zone. Additional counties included in the zone are Chariton, Randolph, and Sullivan.

 


 

Monday, January 26, 2015

 

Missouri MDC reports two new cases of CWD found in Adair and Macon counties

 


 

Friday, September 20, 2013

 

Missouri State records show gaps in oversight of captive deer farms, ranches

 


 

a few escapees off the top of my head ;

 

Tuesday, November 27, 2012

 

Pennsylvania ‘Pink 23’ Adams County exposed CWD Escaped Deer shot, but where are the other escapees ?

 


 

Saturday, June 29, 2013

 

PENNSYLVANIA CAPTIVE CWD INDEX HERD MATE YELLOW *47 STILL RUNNING LOOSE IN INDIANA, YELLOW NUMBER 2 STILL MISSING, AND OTHERS ON THE RUN STILL IN LOUISIANA

 


 

Tuesday, June 11, 2013

 

CWD GONE WILD, More cervid escapees from more shooting pens on the loose in Pennsylvania

 


 

Wisconsin : 436 Deer Have Escaped From Farms to Wild

 

Date: March 18, 2003 Source: Milwaukee Journal Sentinel

 

Contacts: LEE BERGQUIST lbergquist@journalsentinel.com

 

State finds violations, lax record keeping at many sites, report says A state inspection of private deer farms, prompted by the discovery of chronic wasting disease, found that 436 white-tailed deer escaped into the wild, officials said Tuesday

 

The Department of Natural Resources found that captive deer have escaped from one-third of the state's 550 deer farms over the lifetime of the operations. The agency also uncovered hundreds of violations and has sought a total of 60 citations or charges against deer farm operators.

 

Hundreds of deer escape

 

The DNR found a total of 671 deer that escaped farms - 436 of which were never found - because of storm-damaged fences, gates being left open or the animals jumping over or through fences.

 

In one example in Kewaunee County, a deer farmer's fence was knocked down in a summer storm. Ten deer escaped, and the farmer told the DNR he had no intention of trying to reclaim them. The DNR found five of the deer, killed them and cited the farmer for violation of a regulation related to fencing.

 

Another deer farmer near Mishicot, in Manitowoc County, released all nine of his whitetails last summer after he believed the discovery of chronic wasting disease was going to drive down the market for captive deer.

 

The DNR found 24 instances of unlicensed deer farms and issued 19 citations.

 

Game Farms Inspected

 

A summary of the findings of the Department of Natural Resources' inspection of 550 private white-tailed deer farms in the state: The deer farms contained at least 16,070 deer, but the DNR believes there are more deer in captivity than that because large deer farms are unable to accurately count their deer. 671 deer had escaped from game farms, including 436 that were never found.

 

24 farmers were unlicensed. One had been operating illegally since 1999 after he was denied a license because his deer fence did not meet minimum specifications.

 

Records maintained by operators ranged from "meticulous documentation to relying on memory." At least 227 farms conducted various portions of their deer farm business with cash. Over the last three years, 1,222 deer died on farms for various reasons. Disease testing was not performed nor required on the majority of deer. Farmers reported doing business with people in 22 other states and one Canadian province. ..

 


 

Earl Ray Tomblin, Governor Frank Jezioro, Director

 

News Release: November 4, 2011

 

Facebook: WV Commerce - State Parks

 

Hoy Murphy, Public Information Officer (304) 957-9365 hoy.r.murphy@wv.gov Contact: Curtis Taylor, Wildlife Resources Section Chief 304-558-2771 DNR.Wildlife@wv.gov

 

Elk escape from captive cervid facility in Pennsylvania near West Virginia border

 

SOUTH CHARLESTON, W.Va. – The West Virginia Division of Natural Resources (WVDNR) has confirmed with officials from the Pennsylvania Department of Agriculture (PDA) that at least two elk, including one adult bull and one cow, have escaped from a captive cervid facility (deer and elk farms) in Greene County, Pa. Greene County shares a common border with Marshall, Wetzel and Monongalia counties in West Virginia. The elk escaped from a captive cervid facility located approximately three miles from the West Virginia-Pennsylvania border.

 

The PDA regulates captive cervid facilities in Pennsylvania. A representative of the agency was unaware if the recent escaped elk were tagged. The WVDNR regulates captive cervid facilities in West Virginia. In West Virginia, all captive cervids in breeding facilities must be ear-tagged, and there are currently no reported elk escapes from any facility in West Virginia.

 

A bull elk has been seen recently in Wetzel County, W.Va., according to WVDNR officials. There have been no reports of cow elk sightings in either Wetzel County, W.Va., or Greene County, Pa. No free-ranging wild elk live within 150 miles of Wetzel County. The elk sighted in Wetzel County is likely the escaped animal from the captive facility in Pennsylvania.

 


 

Friday, September 28, 2012

 

Stray elk renews concerns about deer farm security Minnesota

 


 

Monday, June 11, 2012

 

*** OHIO Captive deer escapees and non-reporting ***

 


 

Thursday, October 23, 2014

 

FIRST CASE OF CHRONIC WASTING DISEASE CONFIRMED IN OHIO ON PRIVATE PRESERVE

 


 

Thursday, April 02, 2015

 

OHIO CONFIRMS SECOND POSTIVE CHRONIC WASTING DISEASE CWD on Yoder's properties near Millersburg

 


 

Wednesday, February 11, 2015

 

World Class Whitetails quarantined CWD deer Daniel M. Yoder charged with two counts of tampering with evidence

 


 

Friday, April 04, 2014

 

*** Wisconsin State officials kept silent on CWD discovery at game farm ***

 


 

Tuesday, October 07, 2014

 

*** Wisconsin white-tailed deer tested positive for CWD on a Richland County breeding farm, and a case of CWD has been discovered on a Marathon County hunting preserve

 


 

Wednesday, March 04, 2015

 

Disease sampling results provide current snapshot of CWD in Wisconsin finding 324 positive detections statewide in 2014

 


 

Friday, July 17, 2015

 

*** TPW Commission Holds Special Meeting on Chronic Wasting Disease

 


 

Wednesday, July 01, 2015

 

TEXAS Chronic Wasting Disease Detected in Medina County Captive Deer

 


 

Thursday, July 09, 2015

 

TEXAS Chronic Wasting Disease (CWD) Herd Plan for Trace-Forward Exposed Herd with Testing of Exposed Animals

 


 

Tuesday, July 14, 2015

 

Texas Parks and Wildlife Commission Special Meeting Thursday on Chronic Wasting Disease CWD

 


 

Rare report of deer disease in Texas causes stir

 

Houston Chronicle

 

Rare report of deer disease in Texas causes stir, especially since it’s the 8 case of CWD documented in Texas, and the first case of CWD in Captive deer.

 

here is how I would have titled this article, and why.

 

Shannon Tompkins Finally Breaks Silence on Texas First Captive CWD Case and Starts Off Spreading False Information About Risk Factors. ...

 

Thursday, July 16, 2015

 


 

Wednesday, March 18, 2015

 

Chronic Wasting Disease CWD Confirmed Texas Trans Pecos March 18, 2015

 


 

Wednesday, March 25, 2015

 

Chronic Wasting Disease CWD Cases Confirmed In New Mexico 2013 and 2014 UPDATE 2015

 


 

Thursday, May 02, 2013

 

*** Chronic Wasting Disease (CWD) Texas Important Update on OBEX ONLY TEXTING

 


 

Monday, February 11, 2013

 

TEXAS CHRONIC WASTING DISEASE CWD Four New Positives Found in Trans Pecos

 


 

Tuesday, July 10, 2012

 

Chronic Wasting Disease Detected in Far West Texas

 


 

Monday, March 26, 2012

 

Texas Prepares for Chronic Wasting Disease CWD Possibility in Far West Texas

 


 

***for anyone interested, here is some history of CWD along the Texas, New Mexico border, and my attempt to keep up with it...terry

 

snip...

 

see history CWD Texas, New Mexico Border ;

 

Monday, March 26, 2012

 

3 CASES OF CWD FOUND NEW MEXICO MULE DEER SEVERAL MILES FROM TEXAS BORDER

 


 

Sunday, October 04, 2009

 

CWD NEW MEXICO SPREADING SOUTH TO TEXAS 2009 2009 Summary of Chronic Wasting Disease in New Mexico New Mexico Department of Game and Fish

 


 

Friday, May 22, 2015

 

*** Chronic Wasting Disease and Program Updates - 2014 NEUSAHA Annual Meeting 12-14 May 2014

 


 

Sunday, July 12, 2015

 

*** Insights into CWD and BSE species barriers using real-time conversion

 


 

Wednesday, July 15, 2015

 

Kansas Ten Deer Test Positive for CWD in 2014-2015 7-16-15 News

 


 

Wednesday, July 01, 2015

 

DRAFT Virginia Deer Management Plan 2015-2024 (bans urine scents do to CWD 2015)

 


 

Tuesday, July 14, 2015

 

*** TWO Escaped Captive Deer on the loose in Eau Claire County Wisconsin CWD postive farm Yellow ear tag

 


 

Thursday, June 25, 2015

 

Wisconsin CWD-positive white-tailed deer found on Eau Claire County farm

 


 


 

TEXAS MAD COW TRACE BACK EFFORTS ???

 

 

 

 TEXAS MAD COW

 

 THEY DID FINALLY TEST AFTER SITTING 7+ MONTHS ON A SHELF WHILE GW BORE THE BSE MRR POLICY, i.e. legal trading of all strains of TSE. now understand, i confirmed this case 7 months earlier to the TAHC, and then, only after i contacted the Honorable Phyllis Fong and after an act of Congress, this animal was finally confirmed ;

 

 During the course of the investigation, USDA removed and tested a total of 67 animals of interest from the farm where the index animal's herd originated. All of these animals tested negative for BSE. 200 adult animals of interest were determined to have left the index farm. Of these 200, APHIS officials determined that 143 had gone to slaughter, two were found alive (one was determined not to be of interest because of its age and the other tested negative), 34 are presumed dead, one is known dead and 20 have been classified as untraceable. In addition to the adult animals, APHIS was looking for two calves born to the index animal. Due to record keeping and identification issues, APHIS had to trace 213 calves. Of these 213 calves, 208 entered feeding and slaughter channels, four are presumed to have entered feeding and slaughter channels and one calf was untraceable.

 


 

Executive Summary In June 2005, an inconclusive bovine spongiform encephalopathy (BSE) sample from November 2004, that had originally been classified as negative on the immunohistochemistry test, was confirmed positive on SAF immunoblot (Western blot). The U.S. Department of Agriculture (USDA) identified the herd of origin for the index cow in Texas; that identification was confirmed by DNA analysis. USDA, in close cooperation with the Texas Animal Health Commission (TAHC), established an incident command post (ICP) and began response activities according to USDA’s BSE Response Plan of September 2004. Response personnel removed at-risk cattle and cattle of interest (COI) from the index herd, euthanized them, and tested them for BSE; all were negative. USDA and the State extensively traced all at-risk cattle and COI that left the index herd. The majority of these animals entered rendering and/or slaughter channels well before the investigation began. USDA’s response to the Texas finding was thorough and effective.

 

snip...

 

Trace Herd 3

 

The owner of Trace Herd 3 was identified as possibly having received an animal of interest. The herd was placed under hold order on 7/27/05. The herd inventory was conducted on 7/28/05. The animal of interest was not present within the herd, and the hold order was released on 7/28/05. The person who thought he sold the animal to the owner of Trace Herd 3 had no records and could not remember who else he might have sold the cow to. Additionally, a search of GDB for all cattle sold through the markets by that individual did not result in a match to the animal of interest.

 

*** The animal of interest traced to this herd was classified as untraceable because all leads were exhausted.

 

Trace Herd 4

 

The owner of Trace Herd 4 was identified as having received one of the COI through an order buyer. Trace Herd 4 was placed under hold order on 7/29/05. A complete herd inventory was conducted on 8/22/05 and 8/23/05. There were 233 head of cattle that were examined individually by both State and Federal personnel for all man-made identification and brands. The animal of interest was not present within the herd. Several animals were reported to have died in the herd sometime after they arrived on the premises in April 2005. A final search of GDB records yielded no further results on the eartag of interest at either subsequent market sale or slaughter.

 

***With all leads having been exhausted, this animal of interest has been classified as untraceable. The hold order on Trace Herd 4 was released on 8/23/05.

 

Trace Herd 5

 

The owner of Trace Herd 5 was identified as having received two COI and was placed under hold order on 8/1/05. Trace Herd 5 is made up of 67 head of cattle in multiple pastures. During the course of the herd inventory, the owner located records that indicated that one of the COI, a known birth cohort, had been sold to Trace Herd 8 where she was subsequently found alive. Upon completion of the herd inventory, the other animal of interest was not found within the herd.

 

***A GDB search of all recorded herd tests conducted on Trace Herd 5 and all market sales by the owner failed to locate the identification tag of the animal of interest and she was subsequently classified as untraceable due to all leads having been exhausted. The hold order on Trace Herd 5 was released on 8/8/05.

 

Trace Herd 6

 

The owner of Trace Herd 6 was identified as possibly having received an animal of interest and was placed under hold order on 8/1/05. This herd is made up of 58 head of cattle on two pastures. A herd inventory was conducted and the animal of interest was not present within the herd. The owner of Trace Herd 6 had very limited records and was unable to provide further information on where the cow might have gone after he purchased her from the livestock market. A search of GDB for all cattle sold through the markets by that individual did not result in a match to the animal of interest. Additionally, many of the animals presented for sale by the owner of the herd had been re-tagged at the market effectually losing the traceability of the history of that animal prior to re-tagging.

 

*** The animal of interest traced to this herd was classified as untraceable due to all leads having been exhausted. The hold order on Trace Herd 6 was released on 8/3/05.

 

Trace Herd 7

 

The owner of Trace Herd 7 was identified as having received an animal of interest and was placed under hold order on 8/1/05. Trace Herd 7 contains 487 head of cattle on multiple pastures in multiple parts of the State, including a unit kept on an island. The island location is a particularly rough place to keep cattle and the owner claimed to have lost 22 head on the island in 2004 due to liver flukes. Upon completion of the herd inventory, the animal of interest was not found present within Trace Herd 7. A GDB search of all recorded herd tests conducted on Trace Herd 7 and all market sales by the owner failed to locate the identification tag of the animal of interest.

 

*** The cow was subsequently classified as untraceable. It is quite possible though that she may have died within the herd, especially if she belonged to the island unit. The hold order on Trace Herd 7 was released on 8/8/05.

 


 

FDA has determined that each animal could have consumed, at most and in total, five-and-one-half grams - approximately a quarter ounce -- of prohibited material. These animals weigh approximately 600 pounds.

 


 


 

THE USDA JUNE 2004 ENHANCED BSE SURVEILLANCE PROGRAM WAS TERRIBLY FLAWED ;

 

CDC DR. PAUL BROWN TSE EXPERT COMMENTS 2006

 

In an article today for United Press International, science reporter Steve Mitchell writes:

 

Analysis: What that mad cow means

 

By STEVE MITCHELL UPI Senior Medical Correspondent

 

WASHINGTON, March 15 (UPI) -- The U.S. Department of Agriculture was quick to assure the public earlier this week that the third case of mad cow disease did not pose a risk to them, but what federal officials have not acknowledged is that this latest case indicates the deadly disease has been circulating in U.S. herds for at least a decade.

 

The second case, which was detected last year in a Texas cow and which USDA officials were reluctant to verify, was approximately 12 years old.

 

These two cases (the latest was detected in an Alabama cow) present a picture of the disease having been here for 10 years or so, since it is thought that cows usually contract the disease from contaminated feed they consume as calves. The concern is that humans can contract a fatal, incurable, brain-wasting illness from consuming beef products contaminated with the mad cow pathogen.

 

"The fact the Texas cow showed up fairly clearly implied the existence of other undetected cases," Dr. Paul Brown, former medical director of the National Institutes of Health's Laboratory for Central Nervous System Studies and an expert on mad cow-like diseases, told United Press International. "The question was, 'How many?' and we still can't answer that."

 

Brown, who is preparing a scientific paper based on the latest two mad cow cases to estimate the maximum number of infected cows that occurred in the United States, said he has "absolutely no confidence in USDA tests before one year ago" because of the agency's reluctance to retest the Texas cow that initially tested positive.

 

USDA officials finally retested the cow and confirmed it was infected seven months later, but only at the insistence of the agency's inspector general.

 

"Everything they did on the Texas cow makes everything they did before 2005 suspect," Brown said.

 

Despite this, Brown said the U.S. prevalence of mad cow, formally known as bovine spongiform encephalopathy, or BSE, did not significantly threaten human or cattle health.

 

"Overall, my view is BSE is highly unlikely to pose any important risk either in cattle feed or human feed," he said.

 

However, Jean Halloran of Consumers Union in Yonkers, N.Y., said consumers should be troubled by the USDA's secrecy and its apparent plan to dramatically cut back the number of mad cow tests it conducts.

 

"Consumers should be very concerned about how little we know about the USDA's surveillance program and the failure of the USDA to reveal really important details," Halloran told UPI. "Consumers have to be really concerned if they're going to cut back the program," she added.

 

Last year the USDA tested more than 300,000 animals for the disease, but it has proposed, even in light of a third case, scaling back the program to 40,000 tests annually.

 

"They seem to be, in terms of actions and policies, taking a lot more seriously the concerns of the cattle industry than the concerns of consumers," Halloran said. "It's really hard to know what it takes to get this administration to take action to protect the public."

 

The USDA has insisted that the safeguards of a ban on incorporating cow tissue into cattle feed (which is thought to spread the disease) and removal of the most infectious parts of cows, such as the brain and spinal cord, protect consumers. But the agency glosses over the fact that both of these systems have been revealed to be inadequately implemented.

 

The feed ban, which is enforced by the Food and Drug Administration, has been criticized by the Government Accountability Office in two reports, the most recent coming just last year. The GAO said the FDA's enforcement of the ban continues to have weaknesses that "undermine the nation's firewall against BSE."

 

USDA documents released last year showed more than 1,000 violations of the regulations requiring the removal of brains and spinal cords in at least 35 states, Puerto Rico and the Virgin Islands, with some plants being cited repeatedly for infractions. In addition, a violation of similar regulations that apply to beef exported to Japan is the reason why Japan closed its borders to U.S. beef in January six weeks after reopening them.

 

Other experts also question the adequacy of the USDA's surveillance system. The USDA insists the prevalence of mad cow disease is low, but the agency has provided few details of its surveillance program, making it difficult for outside experts to know if the agency's monitoring plan is sufficient.

 

"It's impossible to judge the adequacy of the surveillance system without having a breakdown of the tested population by age and risk status," Elizabeth Mumford, a veterinarian and BSE expert at Safe Food Solutions in Bern, Switzerland, a company that provides advice on reducing mad cow risk to industry and governments, told UPI.

 

"Everybody would be happier and more confident and in a sense it might be able to go away a little bit for (the USDA) if they would just publish a breakdown on the tests," Mumford added.

 

UPI requested detailed records about animals tested under the USDA's surveillance plan via the Freedom of Information Act in May 2004 but nearly two years later has not received any corresponding documents from the agency, despite a federal law requiring agencies to comply within 30 days. This leaves open the question of whether the USDA is withholding the information, does not have the information or is so haphazardly organized that it cannot locate it.

 

Mumford said the prevalence of the disease in U.S. herds is probably quite low, but there have probably been other cases that have so far gone undetected. "They're only finding a very small fraction of that low prevalence," she said.

 

Mumford expressed surprise at the lack of concern about the deadly disease from American consumers. "I would expect the U.S. public to be more concerned," she said.

 

Markus Moser, a molecular biologist and chief executive officer of Prionics, a Swiss firm that manufactures BSE test kits, told UPI one concern is that if people are infected, the mad cow pathogen could become "humanized" or more easily transmitted from person to person.

 

"Transmission would be much easier, through all kinds of medical procedures" and even through the blood supply, Moser said.

 

© Copyright 2006 United Press International, Inc. All Rights Reserved

 


 


 

CDC - Bovine Spongiform Encephalopathy and Variant Creutzfeldt ... Dr. Paul Brown is Senior Research Scientist in the Laboratory of Central Nervous System ... Address for correspondence: Paul Brown, Building 36, Room 4A-05, ...

 


 

PAUL BROWN COMMENT TO ME ON THIS ISSUE

 

Tuesday, September 12, 2006 11:10 AM

 

"Actually, Terry, I have been critical of the USDA handling of the mad cow issue for some years, and with Linda Detwiler and others sent lengthy detailed critiques and recommendations to both the USDA and the Canadian Food Agency." ........TSS

 


 

OR, what the Honorable Phyllis Fong of the OIG found ;

 

Audit Report Animal and Plant Health Inspection Service Bovine Spongiform Encephalopathy (BSE) Surveillance Program ­ Phase II and Food Safety and Inspection Service

 

Controls Over BSE Sampling, Specified Risk Materials, and Advanced Meat Recovery Products - Phase III

 

Report No. 50601-10-KC January 2006

 

Finding 2 Inherent Challenges in Identifying and Testing High-Risk Cattle Still Remain

 


 

Subject: USDA OIG SEMIANNUAL REPORT TO CONGRESS FY 2007 1st Half (bogus BSE sampling FROM HEALTHY USDA CATTLE)

 

Date: June 21, 2007 at 2:49 pm PST

 

Owner and Corporation Plead Guilty to Defrauding Bovine Spongiform Encephalopathy (BSE) Surveillance Program

 

An Arizona meat processing company and its owner pled guilty in February 2007 to charges of theft of Government funds, mail fraud, and wire fraud. The owner and his company defrauded the BSE Surveillance Program when they falsified BSE Surveillance Data Collection Forms and then submitted payment requests to USDA for the services. In addition to the targeted sample population (those cattle that were more than 30 months old or had other risk factors for BSE), the owner submitted to USDA, or caused to be submitted, BSE obex (brain stem) samples from healthy USDA-inspected cattle. As a result, the owner fraudulently received approximately $390,000. Sentencing is scheduled for May 2007.

 

snip...

 

Topics that will be covered in ongoing or planned reviews under Goal 1 include:

 

soundness of BSE maintenance sampling (APHIS),

 

implementation of Performance-Based Inspection System enhancements for specified risk material (SRM) violations and improved inspection controls over SRMs (FSIS and APHIS),

 

snip...

 

The findings and recommendations from these efforts will be covered in future semiannual reports as the relevant audits and investigations are completed.

 

4 USDA OIG SEMIANNUAL REPORT TO CONGRESS FY 2007 1st Half

 


 

*** We describe the transmission of spongiform encephalopathy in a non-human primate inoculated 10 years earlier with a strain of sheep c-scrapie. Because of this extended incubation period in a facility in which other prion diseases are under study, we are obliged to consider two alternative possibilities that might explain its occurrence. We first considered the possibility of a sporadic origin (like CJD in humans). Such an event is extremely improbable because the inoculated animal was 14 years old when the clinical signs appeared, i.e. about 40% through the expected natural lifetime of this species, compared to a peak age incidence of 60–65 years in human sporadic CJD, or about 80% through their expected lifetimes.

 

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

 

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

 

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

 

Emmanuel E. Comoy1 , Jacqueline Mikol1 , Sophie Luccantoni-Freire1 , Evelyne Correia1 , Nathalie Lescoutra-Etchegaray1 , Valérie Durand1 , Capucine Dehen1 , Olivier Andreoletti2 , Cristina Casalone3 , Juergen A. Richt4 n1 , Justin J. Greenlee4 , Thierry Baron5 , Sylvie L. Benestad6 , Paul Brown1 […] & Jean-Philippe Deslys1 - Show fewer authors Scientific Reports 5, Article number: 11573 (2015) doi:10.1038/srep11573 Download Citation

 

Epidemiology | Neurological manifestations | Prion diseases Received: 16 February 2015 Accepted: 28 May 2015 Published online: 30 June 2015 ABSTRACT Classical bovine spongiform encephalopathy (c-BSE) is the only animal prion disease reputed to be zoonotic, causing variant Creutzfeldt-Jakob disease (vCJD) in humans and having guided protective measures for animal and human health against animal prion diseases. Recently, partial transmissions to humanized mice showed that the zoonotic potential of scrapie might be similar to c-BSE. We here report the direct transmission of a natural classical scrapie isolate to cynomolgus macaque, a highly relevant model for human prion diseases, after a 10-year silent incubation period, with features similar to those reported for human cases of sporadic CJD. Scrapie is thus actually transmissible to primates with incubation periods compatible with their life expectancy, although fourfold longer than BSE. Long-term experimental transmission studies are necessary to better assess the zoonotic potential of other prion diseases with high prevalence, notably Chronic Wasting Disease of deer and elk and atypical/Nor98 scrapie.

 

snip...

 

Discussion

 

We describe the transmission of spongiform encephalopathy in a non-human primate inoculated 10 years earlier with a strain of sheep c-scrapie. Because of this extended incubation period in a facility in which other prion diseases are under study, we are obliged to consider two alternative possibilities that might explain its occurrence. We first considered the possibility of a sporadic origin (like CJD in humans). Such an event is extremely improbable because the inoculated animal was 14 years old when the clinical signs appeared, i.e. about 40% through the expected natural lifetime of this species, compared to a peak age incidence of 60–65 years in human sporadic CJD, or about 80% through their expected lifetimes. Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.

 

The second possibility is a laboratory cross-contamination. Three facts make this possibility equally unlikely. First, handling of specimens in our laboratory is performed with fastidious attention to the avoidance of any such cross-contamination. Second, no laboratory cross-contamination has ever been documented in other primate laboratories, including the NIH, even between infected and uninfected animals housed in the same or adjacent cages with daily intimate contact (P. Brown, personal communication). Third, the cerebral lesion profile is different from all the other prion diseases we have studied in this model19, with a correlation between cerebellar lesions (massive spongiform change of Purkinje cells, intense PrPres staining and reactive gliosis26) and ataxia. The iron deposits present in the globus pallidus are a non specific finding that have been reported previously in neurodegenerative diseases and aging27. Conversely, the thalamic lesion was reminiscent of a metabolic disease due to thiamine deficiency28 but blood thiamine levels were within normal limits (data not shown). The preferential distribution of spongiform change in cortex associated with a limited distribution in the brainstem is reminiscent of the lesion profile in MM2c and VV1 sCJD patients29, but interspecies comparison of lesion profiles should be interpreted with caution. It is of note that the same classical scrapie isolate induced TSE in C57Bl/6 mice with similar incubation periods and lesional profiles as a sample derived from a MM1 sCJD patient30.

 

We are therefore confident that the illness in this cynomolgus macaque represents a true transmission of a sheep c-scrapie isolate directly to an old-world monkey, which taxonomically resides in the primate subdivision (parvorder of catarrhini) that includes humans. With an homology of its PrP protein with humans of 96.4%31, cynomolgus macaque constitutes a highly relevant model for assessing zoonotic risk of prion diseases. Since our initial aim was to show the absence of transmission of scrapie to macaques in the worst-case scenario, we obtained materials from a flock of naturally-infected sheep, affecting animals with different genotypes32. This c-scrapie isolate exhibited complete transmission in ARQ/ARQ sheep (332 ± 56 days) and Tg338 transgenic mice expressing ovine VRQ/VRQ prion protein (220 ± 5 days) (O. Andreoletti, personal communication). From the standpoint of zoonotic risk, it is important to note that sheep with c-scrapie (including the isolate used in our study) have demonstrable infectivity throughout their lymphoreticular system early in the incubation period of the disease (3 months-old for all the lymphoid organs, and as early as 2 months-old in gut-associated lymph nodes)33. In addition, scrapie infectivity has been identified in blood34, milk35 and skeletal muscle36 from asymptomatic but scrapie infected small ruminants which implies a potential dietary exposure for consumers.

 

Two earlier studies have reported the occurrence of clinical TSE in cynomolgus macaques after exposures to scrapie isolates. In the first study, the “Compton” scrapie isolate (derived from an English sheep) and serially propagated for 9 passages in goats did not transmit TSE in cynomolgus macaque, rhesus macaque or chimpanzee within 7 years following intracerebral challenge1; conversely, after 8 supplementary passages in conventional mice, this “Compton” isolate induced TSE in a cynomolgus macaque 5 years after intracerebral challenge, but rhesus macaques and chimpanzee remained asymptomatic 8.5 years post-exposure8. However, multiple successive passages that are classically used to select laboratory-adapted prion strains can significantly modify the initial properties of a scrapie isolate, thus questioning the relevance of zoonotic potential for the initial sheep-derived isolate. The same isolate had also induced disease into squirrel monkeys (new-world monkey)9. A second historical observation reported that a cynomolgus macaque developed TSE 6 years post-inoculation with brain homogenate from a scrapie-infected Suffolk ewe (derived from USA), whereas a rhesus macaque and a chimpanzee exposed to the same inoculum remained healthy 9 years post-exposure1. This inoculum also induced TSE in squirrel monkeys after 4 passages in mice. Other scrapie transmission attempts in macaque failed but had more shorter periods of observation in comparison to the current study. Further, it is possible that there are differences in the zoonotic potential of different scrapie strains.

 

The most striking observation in our study is the extended incubation period of scrapie in the macaque model, which has several implications. Firstly, our observations constitute experimental evidence in favor of the zoonotic potential of c-scrapie, at least for this isolate that has been extensively studied32,33,34,35,36. The cross-species zoonotic ability of this isolate should be confirmed by performing duplicate intracerebral exposures and assessing the transmissibility by the oral route (a successful transmission of prion strains through the intracerebral route may not necessarily indicate the potential for oral transmission37). However, such confirmatory experiments may require more than one decade, which is hardly compatible with current general management and support of scientific projects; thus this study should be rather considered as a case report.

 

Secondly, transmission of c-BSE to primates occurred within 8 years post exposure for the lowest doses able to transmit the disease (the survival period after inoculation is inversely proportional to the initial amount of infectious inoculum). The occurrence of scrapie 10 years after exposure to a high dose (25 mg) of scrapie-infected sheep brain suggests that the macaque has a higher species barrier for sheep c-scrapie than c-BSE, although it is notable that previous studies based on in vitro conversion of PrP suggested that BSE and scrapie prions would have a similar conversion potential for human PrP38.

 

Thirdly, prion diseases typically have longer incubation periods after oral exposure than after intracerebral inoculations: since humans can develop Kuru 47 years after oral exposure39, an incubation time of several decades after oral exposure to scrapie would therefore be expected, leading the disease to occur in older adults, i.e. the peak age for cases considered to be sporadic disease, and making a distinction between scrapie-associated and truly sporadic disease extremely difficult to appreciate.

 

Fourthly, epidemiologic evidence is necessary to confirm the zoonotic potential of an animal disease suggested by experimental studies. A relatively short incubation period and a peculiar epidemiological situation (e.g., all the first vCJD cases occurring in the country with the most important ongoing c-BSE epizootic) led to a high degree of suspicion that c-BSE was the cause of vCJD. Sporadic CJD are considered spontaneous diseases with an almost stable and constant worldwide prevalence (0.5–2 cases per million inhabitants per year), and previous epidemiological studies were unable to draw a link between sCJD and classical scrapie6,7,40,41, even though external causes were hypothesized to explain the occurrence of some sCJD clusters42,43,44. However, extended incubation periods exceeding several decades would impair the predictive values of epidemiological surveillance for prion diseases, already weakened by a limited prevalence of prion diseases and the multiplicity of isolates gathered under the phenotypes of “scrapie” and “sporadic CJD”.

 

Fifthly, considering this 10 year-long incubation period, together with both laboratory and epidemiological evidence of decade or longer intervals between infection and clinical onset of disease, no premature conclusions should be drawn from negative transmission studies in cynomolgus macaques with less than a decade of observation, as in the aforementioned historical transmission studies of scrapie to primates1,8,9. Our observations and those of others45,46 to date are unable to provide definitive evidence regarding the zoonotic potential of CWD, atypical/Nor98 scrapie or H-type BSE. The extended incubation period of the scrapie-affected macaque in the current study also underscores the limitations of rodent models expressing human PrP for assessing the zoonotic potential of some prion diseases since their lifespan remains limited to approximately two years21,47,48. This point is illustrated by the fact that the recently reported transmission of scrapie to humanized mice was not associated with clinical signs for up to 750 days and occurred in an extreme minority of mice with only a marginal increase in attack rate upon second passage13. The low attack rate in these studies is certainly linked to the limited lifespan of mice compared to the very long periods of observation necessary to demonstrate the development of scrapie. Alternatively, one could estimate that a successful second passage is the result of strain adaptation to the species barrier, thus poorly relevant of the real zoonotic potential of the original scrapie isolate of sheep origin49. The development of scrapie in this primate after an incubation period compatible with its lifespan complements the study conducted in transgenic (humanized) mice; taken together these studies suggest that some isolates of sheep scrapie can promote misfolding of the human prion protein and that scrapie can develop within the lifespan of some primate species.

 

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

 


 

spontaneous atypical BSE ???

 

if that's the case, then France is having one hell of an epidemic of atypical BSE, probably why they stopped testing for BSE, problem solved $$$

 

As of December 2011, around 60 atypical BSE cases have currently been reported in 13 countries, *** with over one third in France.

 


 

so 20 cases of atypical BSE in France, compared to the remaining 40 cases in the remaining 12 Countries, divided by the remaining 12 Countries, about 3+ cases per country, besides Frances 20 cases. you cannot explain this away with any spontaneous BSe. ...TSS

 

Sunday, October 5, 2014

 

France stops BSE testing for Mad Cow Disease

 


 

Thursday, July 24, 2014

 

*** Protocol for further laboratory investigations into the distribution of infectivity of Atypical BSE SCIENTIFIC REPORT OF EFSA New protocol for Atypical BSE investigations

 


 

snip...

 

IBNC Tauopathy or TSE Prion disease, it appears, no one is sure

 

Posted by flounder on 03 Jul 2015 at 16:53 GMT

 


 

Wednesday, July 15, 2015

 

Additional BSE TSE prion testing detects pathologic lesion in unusual brain location and PrPsc by PMCA only, how many cases have we missed?

 


 

HOUND STUDY

 

*** AS implied in the Inset 25 we must not _ASSUME_ that transmission of BSE to other species will invariably present pathology typical of a scrapie-like disease. ***

 

snip...

 


 

full text ;

 

Saturday, July 18, 2015

 

SPONTANEOUS TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION AKA MAD COW TYPE DISEASE, DOES IT EXIST NATURALLY IN THE FIELD?

 


 

Wednesday, July 15, 2015

 

Additional BSE TSE prion testing detects pathologic lesion in unusual brain location and PrPsc by PMCA only, how many cases have we missed?

 


 

Article

 

Evaluation of the Zoonotic Potential of Transmissible Mink Encephalopathy

 

Emmanuel E. Comoy 1,*, Jacqueline Mikol 1, Marie-Madeleine Ruchoux 1, Valérie Durand 1, Sophie Luccantoni-Freire 1, Capucine Dehen 1, Evelyne Correia 1, Cristina Casalone 2, Juergen A. Richt 3, Justin J. Greenlee 4, Juan Maria Torres 5, Paul Brown 1 and Jean-Philippe Deslys 1

 

1 CEA, Institute of Emerging Diseases and Innovative Therapies (iMETI), Division of Prions and Related Diseases (SEPIA), Route du Panorama, BP6, 92265 Fontenay-aux-Roses, France; E-Mails: jacqueline.mikol@wanadoo.fr (J.M.); mruchoux@yahoo.fr (M.-M.R.); valerie.durand@cea.fr (V.D.); sophie.luccantoni@cea.fr (S.L.); capucine.dehen@cea.fr (C.D.); evelyne.correia@cea.fr (E.C.); paulwbrown@comcast.net (P.B.); jpdeslys@cea.fr (J-P.D.)

 

2 Istituto Zooprofilattico Sperimentale del Piemonte, Via Bologna 148, 10154 Torino, Italy; E-Mail: cristina.casalone@izsto.it (C.C.)

 

3 Kansas State University, College of Veterinary Medicine, K224B Mosier Hall, Manhattan, Kansas 66506-5601 USA; E-Mail: jricht@vet.k-state.edu

 

4 National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, Iowa 50010 USA; E-Mail: justin.greenlee@ars.usda.gov (J.J.G.)

 

5 Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria, Madrid, Spain; E-mail: jmtorres@inia.es

 

* Author to whom correspondence should be addressed; E-Mail: emmanuel.comoy@cea.fr (E.E.C.); Tel.: +33-46-54-90-05; Fax: +33-46-54-93-19.

 

Received: 27 June 2013; in revised form: 28 July 2013 / Accepted: 30 July 2013 / Published: 30 July 2013

 

Abstract: Successful transmission of Transmissible Mink Encephalopathy (TME) to cattle supports the bovine hypothesis for the still controversial origin of TME outbreaks. Human and primate susceptibility to classical Bovine Spongiform Encephalopathy (c-BSE) and the transmissibility of L-type BSE to macaques indicate a low cattle-to-primate species barrier. We therefore evaluated the zoonotic potential of cattle-adapted TME. In less than two years, this strain induced in cynomolgus macaques a neurological disease similar to L-BSE but distinct from c-BSE. TME derived from another donor species (raccoon) induced a similar disease with even shorter incubation periods. L-BSE and cattle-adapted TME were also transmissible to transgenic mice expressing human prion protein (PrP). Secondary transmissions to transgenic mice expressing bovine PrP maintained the features of the three tested bovine strains (cattle TME, c-BSE and L-BSE) regardless of intermediate host. Thus, TME is the third animal prion strain transmissible to both macaques and humanized transgenic mice, suggesting zoonotic potentials that should be considered in the risk analysis of animal prion diseases for human health. Moreover, the similarities between TME and L-BSE are highly suggestive of a link between these strains, and therefore the possible presence of L-BSE for many decades prior to its identification in USA and Europe.

 

OPEN ACCESS Pathogens 2013, 2 521

 

snip...

 

4. Conclusions

 

We have shown that cattle-adapted TME is the third cattle prion strain (joining classical and L-type BSE) to be transmissible both to non-human primates and transgenic mice overexpressing human PrP. However, the successful transmission of raccoon TME to primate, inducing a disease with similar features as cattle TME, extends this notion to TME-related strains independent of host origin. Pathological, biochemical and bioassay investigations converged to demonstrate the similarity between cattle-adapted TME and L-BSE. Together with previous experiments performed in ovinized and bovinized transgenic mice and hamsters [8,9] indicating similarities between TME and L-BSE, the data support the hypothesis that L-BSE could be the origin of the TME outbreaks in North America and Europe during the mid-1900s. The corollary of this notion is the longstanding existence of atypical bovine prion cases in those countries during the same period, if not earlier. Although the risk of L-BSE for public health must be further assessed through studies using the oral route of exposure before drawing definitive conclusions, these data underline the importance of a potential zoonotic risk of L-BSE in the management of consumer protection, particularly in the context of the current relaxation of European policy with respect to BSE.

 

Pathogens 2013, 2 530

 

Keywords: primate; prion; transgenic mice; TME; cattle; raccoon; zoonotic potential

 


 

Evidence That Transmissible Mink Encephalopathy Results from Feeding Infected Cattle

 

Over the next 8-10 weeks, approximately 40% of all the adult mink on the farm died from TME.

 

snip...

 

The rancher was a ''dead stock'' feeder using mostly (>95%) downer or dead dairy cattle...

 


 


 


 

In Confidence - Perceptions of unconventional slow virus diseases of animals in the USA - APRIL-MAY 1989 - G A H Wells

 

3. Prof. A. Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs. ...

 


 

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

 

Thursday, July 24, 2014

 

*** Protocol for further laboratory investigations into the distribution of infectivity of Atypical BSE SCIENTIFIC REPORT OF EFSA New protocol for Atypical BSE investigations

 


 

*** PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS ***

 

THANK YOU PRION 2015 TAYLOR & FRANCIS, Professor Chernoff, and Professor Aguzzi et al, for making these PRION 2015 Congressional Poster and Oral Abstracts available freely to the public. ...Terry S. Singeltary Sr.

 

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

 

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

 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods. We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period, with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold longe 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...TSS

 

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

 

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

 

O18

 

Zoonotic Potential of CWD Prions

 

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

 

Chronic wasting disease (CWD) is a widespread and expanding prion disease in free-ranging and captive cervid species in North America. The zoonotic potential of CWD prions is a serious public health concern. Current literature generated with in vitro methods and in vivo animal models (transgenic mice, macaques and squirrel monkeys) reports conflicting results. The susceptibility of human CNS and peripheral organs to CWD prions remains largely unresolved. In our earlier bioassay experiments using several humanized transgenic mouse lines, we detected protease-resistant PrPSc in the spleen of two out of 140 mice that were intracerebrally inoculated with natural CWD isolates, but PrPSc was not detected in the brain of the same mice. Secondary passages with such PrPSc-positive CWD-inoculated humanized mouse spleen tissues led to efficient prion transmission with clear clinical and pathological signs in both humanized and cervidized transgenic mice. Furthermore, a recent bioassay with natural CWD isolates in a new humanized transgenic mouse line led to clinical prion infection in 2 out of 20 mice. ***These results indicate that the CWD prion has the potential to infect human CNS and peripheral lymphoid tissues and that there might be asymptomatic human carriers of CWD infection.

 

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

 

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

 

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

 

Saturday, May 30, 2015

 

PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS

 


 


 

Thursday, August 12, 2010

 

Seven main threats for the future linked to prions

 

***Also, a link is suspected between atypical BSE and some apparently sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases constitute an unforeseen first threat that could sharply modify the European approach to prion diseases.

 

Second threat

 

snip...

 


 

Monday, October 10, 2011

 

EFSA Journal 2011 The European Response to BSE: A Success Story

 

snip...

 

*** but the possibility that a small proportion of human cases so far classified as "sporadic" CJD are of zoonotic origin could not be excluded. Moreover, transmission experiments to non-human primates suggest that some TSE agents in addition to Classical BSE prions in cattle (namely L-type Atypical BSE, Classical BSE in sheep, transmissible mink encephalopathy (TME) and chronic wasting disease (CWD) agents) might have zoonotic potential.

 

snip...

 


 


 

***In addition, non-human primates are specifically susceptible for atypical BSE as demonstrated by an approximately 50% shortened incubation time for L-type BSE as compared to C-type. Considering the current scientific information available, it cannot be assumed that these different BSE types pose the same human health risks as C-type BSE or that these risks are mitigated by the same protective measures.

 


 

Thursday, June 04, 2015

 

Catholic Medical Center v. Civil No. 14-cv-180-JL Opinion No. 2015 DNH 110 Fireman’s Fund Insurance Company Creutzfeldt Jakob Disease TSE Prion tainted medical instruments

 

UNITED STATES DISTRICT COURT DISTRICT OF NEW HAMPSHIRE

 


 

Tuesday, May 26, 2015

 

Minimise transmission risk of CJD and vCJD in healthcare settings Last updated 15 May 2015

 


 

2015 PRION CONFERENCE

 

*** RE-P.164: Blood transmission of prion infectivity in the squirrel monkey: The Baxter study

 

***suggest that blood donations from cases of GSS (and perhaps other familial forms of TSE) carry more risk than from vCJD cases, and that little or no risk is associated with sCJD. ***

 

ran across an old paper from 1984 ;

 

***The occurrence of contact cases raises the possibility that transmission in families may be effected by an unusually virulent strain of the agent. ***

 


 

***suggest that blood donations from cases of GSS (and perhaps other familial forms of TSE) carry more risk than from vCJD cases, and that little or no risk is associated with sCJD...see;

 

P.164: Blood transmission of prion infectivity in the squirrel monkey: The Baxter study

 

Paul Brown1, Diane Ritchie2, James Ironside2, Christian Abee3, Thomas Kreil4, and Susan Gibson5 1NIH (retired); Bethesda, MD USA; 2University of Edinburgh; Edinburgh, UK; 3University of Texas; Bastrop, TX USA; 4Baxter Bioscience; Vienna, Austria; 5University of South Alabama; Mobile, AL USA

 

Five vCJD disease transmissions and an estimated 1 in 2000 ‘silent’ infections in UK residents emphasize the continued need for information about disease risk in humans. A large study of blood component infectivity in a non-human primate model has now been completed and analyzed. Among 1 GSS, 4 sCJD, and 3 vCJD cases, only GSS leukocytes transmitted disease within a 5–6 year surveillance period. A transmission study in recipients of multiple whole blood transfusions during the incubation and clinical stages of sCJD and vCJD in ic-infected donor animals was uniformly negative. These results, together with other laboratory studies in rodents and nonhuman primates and epidemiological observations in humans, ***suggest that blood donations from cases of GSS (and perhaps other familial forms of TSE) carry more risk than from vCJD cases, and that little or no risk is associated with sCJD. The issue of decades-long incubation periods in ‘silent’ vCJD carriers remains open.

 

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

 

***suggest that blood donations from cases of GSS (and perhaps other familial forms of TSE) carry more risk than from vCJD cases, and that little or no risk is associated with sCJD...see;

 

Wednesday, December 11, 2013

 

*** Detection of Infectivity in Blood of Persons with Variant and Sporadic Creutzfeldt-Jakob Disease ***

 


 

THE BAXTER STUDY...SEE MORE HERE ;

 


 


 

From: Terry S. Singeltary Sr.

 

Sent: Saturday, November 15, 2014 9:29 PM

 

To: Terry S. Singeltary Sr.

 

Subject: THE EPIDEMIOLOGY OF CREUTZFELDT-JAKOB DISEASE R. G. WILL 1984

 

THE EPIDEMIOLOGY OF CREUTZFELDT-JAKOB DISEASE

 

R. G. WILL

 

1984

 

snip...

 


 

THE BAXTER STUDY...SEE MORE HERE ;

 


 


 

TSS

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