Saturday, January 31, 2015

Chronic wasting disease found in bull elk killed on private Utah ranch

Chronic Wasting Disease in One Domestic Elk

 Details Category: News Published on Tuesday, 03 February 2015 16:47 Written by Larry Lewis 

 Statement Regarding Confirmation of Chronic Wasting Disease in One Domestic Elk

 The office of the State Veterinarian confirms that one domestic bull elk has tested positive for Chronic Wasting Disease (CWD). The discovery came following routine testing of a male elk that was harvested by a hunter at the Broadmouth Canyon Ranch in Weber County.

 The infected animal was among 11 elk transported in early October, 2014 to the hunting ranch from the Howe’s Elk Ranch in San Juan County. All but two of the remaining 10 animals tested negative. Tests on the remaining two are currently being conducted with results expected shortly. Both elk ranches are under quarantine, which prohibits any elk from being moved from either facility. State Veterinarians are working with the State Veterinary Diagnostic Laboratory in Logan, Utah and the National Veterinary Services Laboratory (NVSL) in Ames, Iowa to confirm the origin of the infected animal. As a means to prevent the spread of CWD, the State Veterinarian’s Office is recommending the remaining elk at the San Juan County ranch be euthanized and tested.

 This is the first confirmed case of CWD in domestic elk in Utah since the creation of the Domestic Elk Act in 1997. CWD has been present in wild deer in Utah since 2002 and wild elk since 2009. Chronic Wasting Disease is a rare disease affecting the brains of mule deer, black-tailed deer, white-tailed deer, elk, and moose. The disease belongs to a group of diseases called transmissible spongiform encephalopathies (TSEs).. There is no known cure for TSEs, and they are always fatal in susceptible host species. There is no scientific evidence that CWD can spread to humans. The Center of Disease Control has thoroughly investigated any connection between CWD and the human forms of TSEs and stated, “the risk of infection with the CWD agent among hunters is extremely small, if it exists at all,” and “it is extremely unlikely that CWD would be a food borne hazard.


 Contact: Dr. Warren Hess (801) 538-4910 Larry Lewis (801) 538-7104 Cell (801) 514-2152

Chronic wasting disease found in bull elk killed on private Utah ranch


By BRETT PRETTYMAN | The Salt Lake Tribun connect First Published Jan 30 2015 04:00PM • Last Updated Jan 30 2015 10:22 pm


A bull elk shot in a private northern Utah hunting park has tested positive for chronic wasting disease (CWD), Utah Department of Agriculture officials confirmed to the Salt Lake Tribune Friday.


Confirmation of the neurological disease's presence means the approximately 20 wild deer and two moose fenced in on the Broadmouth Canyon Ranch in Liberty will have to be killed to be tested.


The entire herd of elk — more than 60 animals — at the Howe's Elk Ranching operation near Blanding, where the CWD-positive bull came from, will also have to be destroyed and tested.


 "The bull came from the farm in southeastern Utah as part of a group of 11 bulls," said Utah state veterinarian Warren Hess. Hunters at the


Broadmouth Canyon Ranch killed nine of the bulls, and tests on one of them came back positive, he said. As a result, ranch owners killed the last two bull elk. "We are waiting for the results on those animals," Hess said.


Hess said Howe's Elk Ranch is under quarantine while the state works with the U.S. Department of Agriculture to seek compensation for the elk. The CWD-infected bull had been at the Liberty hunting park for less than three weeks when it was killed. The state mandates testing of all animals killed at private elk farms or hunting parks, and the bull's results came back positive just before Christmas.


"There wasn't a long exposure and so far that is the only animal to test positive," Hess said. "We have two areas of concern: the park itself and the deer inside the park and the chance of them being infected and getting back out."


It is unknown where the elk at Howe's Elk Ranch picked up CWD. Hess said records show there has been no movement of elk into the the Blanding ranch for the past five years.


Utah Division of Wildlife Resources (DWR) officials are making plans to hunt the deer and moose in the Broadmouth Canyon Ranch enclosure to test for CWD and to prevent them from escaping and reaching other wild animals.


"We will work with the Department of Agriculture to minimize the risk of contact between domestic and wild animals," said DWR's mammals coordinator Leslie McFarlane, who oversees the state's wildlife disease program.


Chronic wasting disease is not new to Utah wildlife. The disease is sometimes compared to mad cow disease, but is not deemed to be transmittable to humans.


It first showed up in Utah in 2002 when a buck mule deer killed during the rifle hunt near Vernal tested positive. A doe mule deer found dead in a field near Moab in 2003 was the second known case of CWD in Utah. Since then, according to McFarlane, there have 62 cases of CWD in Utah. Two elk have been confirmed to have CWD.


A map showing the distribution of CWD in Utah between 2003 and 2013 shows no evidence of the malady near Liberty where the Broadmouth Canyon hunting park is located.


DWR biologists conduct annual CWD testing in areas where it is prevalent and at random locations across the state to monitor Utah's herds.


"We will increase our monitoring around the two facilities by looking at live animals that appear sick and doing tests on road kill," McFarlane said. "If people see sick animals we would ask that they let us know."


Hess said operators at both elk facilities have been working with the Department of Agriculture to address the issue.


Broadmouth Canyon Ranch is owned by the family of former Utah State University football player and National Football League All-Pro Rulon Jones. The state has had issues with fence breaches at Broadmouth Canyon in the past. The family also operates an elk hunting ranch in Idaho and two hunting ranches in Mexico.


Hess said the department is not aware of any movement of elk from the Utah ranch to the Idaho ranch, which is in the Blackfoot Mountains.



Chronic Wasting Disease has been found in three different geographic areas within Utah (see CWD positive map). The disease was first discovered in Utah in 2002 in a buck taken during the rifle hunt near Vernal. A second positive was discovered in Utah in early 2003, when a mule deer doe that died in an agricultural field near Moab, Utah, also tested positive. A third area of Utah was found with CWD in late 2003 when a mule deer doe taken in a depredation situation near Fountain Green tested positive. To date, 56 mule deer and one elk have tested positive for CWD in Utah. The highest prevalence rate (two percent in the buck population) in Utah is found on Wildlife Management Unit (WMU) 13, the La Sal Mountains, where 38 of the 56 cases have been found. Prevalence rates are less than one percent in the other two areas of Utah, near Vernal (WMU 9) and Fountain Green (WMU 16). Copyright © 2013 State of Utah






Wednesday, December 21, 2011


CWD UTAH San Juan deer hunting unit



Friday, March 12, 2010


Elk tests positive for CWD UTAH Posted Thursday, 11 March 2010




-------- Original Message --------


Subject: Two more deer in eastern Utah test positive for chronic wasting disease


Date: Thu, 18 Sep 2003 09:36:22 –0500


From: "Terry S. Singeltary Sr."


Reply-To: Bovine Spongiform Encephalopathy




######## Bovine Spongiform Encephalopathy #########


Posted Wednesday, September 17, 2003


Two more deer in eastern Utah test positive for chronic wasting disease


SALT LAKE CITY Two buck deer taken in Utah during this year's archery hunt have tested positive for chronic wasting disease, the Division of Wildlife Resources announced Sept. 17.


Both of the deer were taken in eastern Utah. One was taken on Diamond Mountain north of Vernal. The other was taken on the LaSal Mountains east of Moab. Both deer were adult animals, meaning they were at least two years old. The hunters who took the deer have been notified that the animals they took had chronic wasting disease (CWD).


CWD was first confirmed in deer in Utah in February 2003. To date, four deer in eastern Utah have tested positive for the disease, which is fatal to deer and elk that contract it. According to the World Health Organization, there is currently no evidence that CWD can be transmitted to humans from infected deer and elk.


"We sampled 205 deer taken on 17 units across the state during the archery hunt, and these are the only deer that have tested positive so far," said Leslie McFarlane, wildlife biologist for the Division of Wildlife Resources. "Our conservation officers and biologists in the 17 units will take samples in the field from deer taken during the upcoming muzzleloader buck deer hunt. We'll also set up check stations during the opening weekend of the general rifle hunt in October to test more."


Hunters who take a deer on any of the 17 units during the muzzleloader hunt can also have their animal checked at any of the DWR's six offices. The offices are open Mondays through Fridays, from 8 a.m. to 5 p.m.


To obtain a proper tissue sample, the animal must be at least one year old and the sample must be collected within 48 hours of the animal being killed. The head must be kept cool but not frozen.


"We're only sampling deer that have been taken on the 17 units this year," McFarlane said. "If we get enough samples to obtain the statistics we need, we'll switch and sample the remaining units next year."


Maps of the units that are being sampled are available on this Web site or at any DWR office. The DWR Web site also includes additional information about CWD and links to other Web sites where people can learn more about the disease.


For more information, call the nearest Division of Wildlife Resources office or the DWR's Salt Lake City office at (801) 538-4700.






Tuesday, December 20, 2011


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


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 been cut 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.





Thursday, January 15, 2015


*** INDIANA HB1453 - high fence hunting preserve bill has been introduced by Rep. Sean Eberhart and he received monetary contribution from Indiana Deer and Elk Farmers Advocates INC.



Friday, January 16, 2015


Indiana SENATE BILL No. 442 Miller Pete Hunting wildlife Removes exotic mammals from the animals that may be propagated or offered for hunting at a shooting preserve Makes it a Class C misdemeanor



Tuesday, January 06, 2015


APHIS Provides Additional Information on Chronic Wasting Disease (CWD) Indemnity Requests January 5, 2015 05:26 PM EST



***please read this***


98 | Veterinary Record | January 24, 2015




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.






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: 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.






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





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.





PO-039: A comparison of scrapie and chronic wasting disease in white-tailed deer


Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture; Agricultural Research Service, National Animal Disease Center; Ames, IA USA




The results of this study suggest that there are many similarities in the manifestation of CWD and scrapie in WTD after IC inoculation including early and widespread presence of PrPSc in lymphoid tissues, clinical signs of depression and weight loss progressing to wasting, and an incubation time of 21-23 months. Moreover, western blots (WB) done on brain material from the obex region have a molecular profile similar to CWD and distinct from tissues of the cerebrum or the scrapie inoculum. However, results of microscopic and IHC examination indicate that there are differences between the lesions expected in CWD and those that occur in deer with scrapie: amyloid plaques were not noted in any sections of brain examined from these deer and the pattern of immunoreactivity by IHC was diffuse rather than plaque-like.


*** After a natural route of exposure, 100% of WTD were susceptible to scrapie.


Deer developed clinical signs of wasting and mental depression and were necropsied from 28 to 33 months PI. Tissues from these deer were positive for PrPSc by IHC and WB. Similar to IC inoculated deer, samples from these deer exhibited two different molecular profiles: samples from obex resembled CWD whereas those from cerebrum were similar to the original scrapie inoculum. On further examination by WB using a panel of antibodies, the tissues from deer with scrapie exhibit properties differing from tissues either from sheep with scrapie or WTD with CWD. Samples from WTD with CWD or sheep with scrapie are strongly immunoreactive when probed with mAb P4, however, samples from WTD with scrapie are only weakly immunoreactive. In contrast, when probed with mAb’s 6H4 or SAF 84, samples from sheep with scrapie and WTD with CWD are weakly immunoreactive and samples from WTD with scrapie are strongly positive. This work demonstrates that WTD are highly susceptible to sheep scrapie, but on first passage, scrapie in WTD is differentiable from CWD.





*** After a natural route of exposure, 100% of white-tailed deer were susceptible to scrapie.



*** We conclude that TSE infectivity is likely to survive burial for long time periods with minimal loss of infectivity and limited movement from the original burial site. However PMCA results have shown that there is the potential for rainwater to elute TSE related material from soil which could lead to the contamination of a wider area. These experiments reinforce the importance of risk assessment when disposing of TSE risk materials.


*** The results show that even highly diluted PrPSc can bind efficiently to polypropylene, stainless steel, glass, wood and stone and propagate the conversion of normal prion protein. For in vivo experiments, hamsters were ic injected with implants incubated in 1% 263K-infected brain homogenate. Hamsters, inoculated with 263K-contaminated implants of all groups, developed typical signs of prion disease, whereas control animals inoculated with non-contaminated materials did not.








Conclusions. To our knowledge, this is the first established experimental model of CWD in TgSB3985. We found evidence for co-existence or divergence of two CWD strains adapted to Tga20 mice and their replication in TgSB3985 mice. Finally, we observed phenotypic differences between cervid-derived CWD and CWD/Tg20 strains upon propagation in TgSB3985 mice. Further studies are underway to characterize these strains.


We conclude that TSE infectivity is likely to survive burial for long time periods with minimal loss of infectivity and limited movement from the original burial site. However PMCA results have shown that there is the potential for rainwater to elute TSE related material from soil which could lead to the contamination of a wider area. These experiments reinforce the importance of risk assessment when disposing of TSE risk materials.


The results show that even highly diluted PrPSc can bind efficiently to polypropylene, stainless steel, glass, wood and stone and propagate the conversion of normal prion protein. For in vivo experiments, hamsters were ic injected with implants incubated in 1% 263K-infected brain homogenate. Hamsters, inoculated with 263K-contaminated implants of all groups, developed typical signs of prion disease, whereas control animals inoculated with non-contaminated materials did not.


Our data establish that meadow voles are permissive to CWD via peripheral exposure route, suggesting they could serve as an environmental reservoir for CWD. Additionally, our data are consistent with the hypothesis that at least two strains of CWD circulate in naturally-infected cervid populations and provide evidence that meadow voles are a useful tool for CWD strain typing.


Conclusion. CWD prions are shed in saliva and urine of infected deer as early as 3 months post infection and throughout the subsequent >1.5 year course of infection. In current work we are examining the relationship of prionemia to excretion and the impact of excreted prion binding to surfaces and particulates in the environment.


Conclusion. CWD prions (as inferred by prion seeding activity by RT-QuIC) are shed in urine of infected deer as early as 6 months post inoculation and throughout the subsequent disease course. Further studies are in progress refining the real-time urinary prion assay sensitivity and we are examining more closely the excretion time frame, magnitude, and sample variables in relationship to inoculation route and prionemia in naturally and experimentally CWD-infected cervids.


Conclusions. Our results suggested that the odds of infection for CWD is likely controlled by areas that congregate deer thus increasing direct transmission (deer-to-deer interactions) or indirect transmission (deer-to-environment) by sharing or depositing infectious prion proteins in these preferred habitats. Epidemiology of CWD in the eastern U.S. is likely controlled by separate factors than found in the Midwestern and endemic areas for CWD and can assist in performing more efficient surveillance efforts for the region.


Conclusions. During the pre-symptomatic stage of CWD infection and throughout the course of disease deer may be shedding multiple LD50 doses per day in their saliva. CWD prion shedding through saliva and excreta may account for the unprecedented spread of this prion disease in nature.


see full text and more ;


Monday, June 23, 2014






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


Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3



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



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



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



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



Rapid assessment of bovine spongiform encephalopathy prion inactivation by heat treatment in yellow grease produced in the industrial manufacturing process of meat and bone meals



Sunday, December 21, 2014


Mucosal immunization with an attenuated Salmonella vaccine partially protects white-tailed deer from chronic wasting disease



Friday, December 19, 2014


Pan-Provincial Vaccine Enterprise Inc. (PREVENT) Conducting a Chronic Wasting Disease (CWD) Vaccine Efficacy Trial in Elk



CHRONIC WASTING DISEASE CWD TSE PRION, how much does it pay to find CWD $$$


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.






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




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.




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.




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).




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.




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.




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.





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



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



when an industry is catering to the public, with products which can risk human and animal health, in my opinion, you should have NO property rights. you should not be able to hide behind property rights when you are clearly risking human and animal health from your product, or the way you handle that product. if you are going to raise, grow, produce a product for the consumer, you have an obligation NOT to risk the public domain, public property, and or the wild animal populations. just my opinion, I still have that right in 2015. ... CHRONIC WASTING DISEASE CWD TSE PRION, how much does it pay to find CWD $$$


CWD, spreading it around...


Tuesday, January 06, 2015


APHIS Provides Additional Information on Chronic Wasting Disease (CWD) Indemnity Requests January 5, 2015 05:26 PM EST





Tuesday, November 04, 2014


*** Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011








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