-The sick female reindeer (Rangifer tarandus tarandus) was detected in the middle of March 2016 in connection with capture for GPS-collaring using helicopter performed by the Norwegian Institute for Nature Research (NINA. It died and the carcass was submitted to the Norwegian Veterinary Institute in Oslo for necropsy and laboratory examinations. It was an adult animal, says wildlife pathologist Turid Vikøren at Norwegian Veterinary Institute, who performed the necropsy.
The body condition of the reindeer was below medium, but it had still some adipose tissue left. In cervids older than 18 months, we routinely collect sample of the brain for CWD examination as part of the national surveillance program for CWD, and that was also done in this reindeer, Vikøren continues.
The head of the Norwegian Reference Laboratory for animal prion diseases at Norwegian Veterinary Institute, Sylvie Benestad, states that the brain sample from the reindeer was positive for the detection of prions both by the first routine test (ELISA-test) and in two supplementary tests (Western Blotting, Immunohistochemistry).
Chronic Wasting Disease is a contagious neurological disease that attacks the brain of cervids. CWD belongs to a group of diseases known as Transmissible Spongiform Encephalopathies (TSEs), in which the infectious agents are known to be the prion protein, a normal protein that misfolds and destroys the brain. The development of the disease is slow and affected cervids show loss of body condition and altered behaviour. Death is inevitable once clinical disease occurs.
CWD is an endemic disease in North America, in which natural infections occurs in mule deer (Odocoileus hemionus), white-tailed deer (O. virginianus), elk (Cervus elaphus nelsoni) og moose (Alces alces shirasi).The reindeer from Norway represents the first detection of CWD in Europe. Also, this is the first detection of a natural infection in reindeer worldwide.
Turid Vikøren (Wildlife Health)
Kjell Handeland (Wildlife Health)
Sylvie Benestad (Prions Diseases)
Jorun Jarp, Head of Dep. of Health Surveillance Mobile: 90056216.
Asle Haukaas, Communication Director Mobile: 92080877.
Chronic wasting disease (CWD) has been recognized as an important prion disease in native North American deer and Rocky Mountain elk. 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 Dec 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, a CWD surveillance program was initiated by the Ministry of Agriculture and Forestry (MAF) in 2001. All elk imported in 1997 were traced back; however, elk 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.
A total of 9 elk 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 elk and 2 elk — were diagnosed in 2004 and 2005. Since February 2005, when slaughtered elk were found to be positive, all slaughtered cervids for human consumption at abattoirs were designated as targets of the CWD surveillance program.
Currently, CWD laboratory testing is only conducted by the National Reference Laboratory on CWD, which is the Foreign Animal Disease Division (FADD) of the National Veterinary Research and Quarantine Service (NVRQS).
In July 2010, one out of 3 elk from Farm 1 slaughtered for human consumption were confirmed as positive. Consequently, all cervids — 54 elk, 41 Sika deer and 5 Albino deer — were culled, and one elk was found to be positive. Epidemiological investigation was conducted by the Veterinary Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary services.
Epidemiologically-related farms were searched for: 3 farms were found, and all cervids at these farms were culled and subjected to CWD diagnostic [testing]. Three elk and 5 crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2. All cervids at Farm 3 and Farm 4 — 15 elk and 47 elk — were culled and confirmed negative. Further epidemiological investigation showed that these CWD outbreaks were linked to the importation of elk from Canada in 1994 based on circumstantial evidence.
In December 2010, one elk was confirmed positive at Farm 5. Consequently, all cervids — 3 elk, 11 Manchurian Sita deer and 20 Sika deer — were culled, and one Manchurian Sika deer and 7 Sika deer were found to be positive. This is the 1st report of CWD in these sub-species of deer.
Epidemiological investigation found that the owner of Farm 2 in the CWD outbreaks of July 2010 had co-owned Farm 5. In addition, it was newly revealed that one positive elk was introduced from Farm 6 of Jinju-si Gyeongsang Namdo. All cervids — 19 elk, 15 crossbreeds (species unknown) and 64 Sika deer — of Farm 6 were culled, but all were confirmed negative.
Mother to Offspring Transmission of Chronic Wasting Disease Candace K. Mathiason, Amy V. Nalls, Kelly Anderson, Jeanette Hayes-Klug, Nicholas Haley and Edward A. Hoover Colorado State University, Department of Microbiology, Immunology and Pathology, Fort Collins, CO USA Key words: Chronic wasting disease, vertical transmission, muntjac deer We have developed a new cervid model in small Asian muntjac deer (Muntiacus reevesi) to study potential modes of vertical transmission of chronic wasting disease (CWD) from mother to offspring. Eight of eight (8/8) muntjac doe orally infected with CWD tested PrPCWD lymphoid positive by 4 months post infection. Six fawns were born to these CWD-infected doe. Six fawns were born to 6 CWD-infected doe; 4 of the fawns were non-viable. The viable fawns have been monitored for CWD infection by immunohistochemistry and sPMCA performed on serial tonsil and rectal lymphoid tissue biopsies. PrPCWD has been detected in one fawn as early as 40 days of age. Moreover, sPMCA performed on rectal lymphoid tissue has yield positive results on another fawn at 10 days of age. In addition, sPMCA assays have also demonstrated amplifiable prions in maternal placental (caruncule) and mammary tissue of the dam. Additional pregnancy related fluids and tissues from the doe as well as tissue from the nonviable fawns are currently being probed for the presence of CWD. In summary, we have employed the muntjac deer model, to demonstrate for the first time the transmission of CWD from mother to offspring. These studies provide the foundation to investigate the mechanisms and pathways of maternal prion transfer. PRION 2010 Meeting Report International Prion Congress: From agent to disease; September 8-11, 2010; Salzburg, Austria Volume 4, Issue 3 July/August/September 2010
EDMONTON – University of Alberta scientists will use new funding to find out how much testing needs to be done before consumers are confident the beef they’re eating is BSE-free.
The study is one of four projects to share in $1.9 million awarded to U of A researchers by PrioNet. The network pulls together scientists from across the country, as well as members of government, non-government organizations and industry, to work on the ultimate goal of eradicating the impact of prion disease.
Prion diseases include bovine spongiform encephalopathy (commonly known as mad cow disease), Creutzfeldt-Jakob disease (CJD) in humans, a variant human form of CJD acquired from the consumption of BSE-contaminated cattle products (vCJD), and chronic wasting disease (CWD) in deer and elk.
Prion diseases are untreatable, infectious, and fatal neurodegenerative diseases.
Normal prion proteins are found on the surface of human and animal cells.
Prion diseases occur when the normal prion protein is misshapen into the infectious disease-causing form, called prions. Scientists are still trying to figure out how the misshaping occurs.
Another one of the projects to get new funding will use X-ray crystallography to determine the 3-D make-up of a molecule. This will provide important molecular information about blocking the misshaping of a prion protein into the disease-causing, infectious prion.
Researchers at the University of Saskatchewan have been given a $1.2 million boost in their efforts to find solutions to threats posed by prion diseases.
The funding, provided by PrioNet Canada, is part of an $8 million total injection into 19 projects by 60 researchers across the country. The goal is to accelerate discoveries surrounding prion diseases such as bovine spongiform encephalopathy (BSE, commonly known as mad cow), chronic wasting disease (CWD) in deer and elk, and Creutzfeldt-Jakob disease (CJD), a variant human form of CJD acquired through the consumption of BSE-contaminated cattle products.
“Ultimately, these projects will translate to safer food, health, and environmental systems for Canadians,” PrioNet scientific director Dr. Neil Cashman stated in a news release about the funding announcements.
Prion diseases are untreatable, infectious, and fatal neurodegenerative diseases. Normal prion proteins are found on the surface of the cells of both humans and animals. Prion diseases occur when the normal prion protein is misshapen into the infectious disease-causing form. Research is still trying to determine exactly how the misshaping occurs. Prions represent a new class of infectious agents that cause disease because, unlike other viruses or bacteria, prions do not contain any DNA or RNA.
Dr. Andrew Potter from the Vaccine and Infectious Disease Organization (VIDO), based at the U of S, is heading up the work on developing a BSE vaccine for cattle. This vaccine would not only provide the first preventative treatment against BSE, but also considerable cost savings to Canada as current BSE-testing regimes are expensive and cumbersome. Furthermore, Potter’s research may lead to vaccines that will aid in the prevention of other prion diseases.
The other U of S project, intended to minimize the spread of CWD in wild deer, is being led by Dr. Trent Bollinger. To date, culling infected herds has been the main practice to try stopping the spread of CWD, but such efforts have not been successful. In addition, the persistent spread of CWD in wild deer leads to increased transmission risks to other species, like moose, or even humans.
Bollinger’s study will provide key data on movement patterns of wild deer in the environment and evaluate the effects deer culling and the presence of feed supplements have on the transmission of CWD in wild deer. This information will help shape policy and wildlife management strategies to reduce the incidence and spread of CWD.
The economic crisis resulting from the May 2003 discovery of a Canadian BSE-infected cow spurred the research. PrioNet Canada, established in 2005 through the federal government’s Networks of Centres of Excellence program, was created to position Canada as a world leader in prion disease research.