Chronic Wasting Disease

Recent News

June 1, 2009 - Deer Samples Negative for CWD, TB

Samples taken from North Dakota deer, elk and moose during the 2008 hunting season have tested negative for chronic wasting disease and bovine tuberculosis, according to Dr. Dan Grove, wildlife veterinarian for the North Dakota Game and Fish Department.
Last fall, samples for CWD testing were taken from nearly 2,300 deer (with 1,600 taken from the targeted area of the central third of the state), 53 elk and 24 moose.
“In addition to our CWD surveillance, we started routine bovine TB surveillance in the northeast, and random sampling throughout the state,” Grove said. “Altogether, 850 deer, moose and elk tested negative for bovine TB.”
Since January approximately 160 moose and deer that died or were showing clinical signs of disease were sampled for CWD and TB as part of the Game and Fish Department’s year-around targeted surveillance. To date, all animals have tested negative for CWD, and bovine TB test results are still pending.
“As always, the success of our surveillance program could not be accomplished without the cooperative efforts of hunters, meat processors, taxidermists and local establishments,” Grove said.
The Game and Fish Department’s three-year cycle of sampling the entire state for CWD will conclude this fall by testing deer from the western third of the state. Grove said a new cycle will begin in 2010 in the eastern third of the state. “We will also continue to test animals in northeastern North Dakota for TB until it has been eradicated from the adjacent Minnesota herd,” Grove added, “and will continue to sample suspect or high risk cases of CWD and TB throughout the year.”
Since 2002, more than 12,300 North Dakota deer, nearly 360 elk and 60 moose have tested negative for CWD. To date, CWD and TB have not been diagnosed in wild or farmed cervids in North Dakota, although these diseases have been found in surrounding states and provinces.

September 15, 2008 - Proclamation Signed as a Precaution Against Spread of CWD

What if I am hunting in a unit, state, or province not listed above?
North Dakotans hunting in a state or province that has not identified CWD or is hunting in an area within a state or province not listed is asked to follow the guidelines listed above as recommendations to minimize any potential spread of disease.

What Common Sense Precautions Should Hunters Take When Handling Or Processing Deer And Elk?
There is no scientific evidence that CWD can be naturally transmitted to humans. However, as a general precaution, NDGFD and health officials advise that hunters take the following common sense precautions when handling and processing deer or elk in areas known to have CWD:

1. Avoid sick animals. Do not shoot, handle, or consume any animal that appears sick; contact your local wildlife agency personnel.
2. Wear rubber/latex gloves when field dressing carcasses.
3. Do not consume and minimize handling the brain, spinal cord, eyes, spleen, tonsils, and lymph nodes of any deer or elk (Normal field dressing coupled with boning out a carcass will remove most, if not all, of these body parts. Cutting away all fatty tissue will remove remaining lymph nodes.)
4. Bone out the meat from the animal.
5. Thoroughly wash hands, knives, and other tools used to field dress the animal. Disinfect tools by soaking them in a solution of 50% unscented household bleach and 50% water for an hour. Afterwards, allow them to air dry.
6. Avoid contact or consumption of any animal that appears sick.
7. Request that your venison is processed separately from other hunter's venison.
8. Bones and unprocessed remains should be disposed through burial, landfill, or incineration.

What Is Chronic Wasting Disease?
Chronic wasting disease (CWD) is a progressive, fatal disease of the nervous system of white-tailed deer, mule deer, and elk. It belongs to a family of diseases known as Transmissible Spongiform Encephalopathies (TSEs), or prion diseases. Although CWD shares certain features with other TSEs, like bovine spongiform encephalopathy (BSE or mad cow disease), scrapie in sheep and goats, and Creutzfeldt - Jakob disease (CJD) in humans, it is a distinct disease apparently affecting only deer and elk. It causes damage to portions of the brain; creating holes in the brain cells and causing a sponge-like appearance.

Where Is It Found?
The origin of CWD in unknown and it may never be possible to definitely determine how or when CWD arose. It was first diagnosed in a Colorado elk research facility in 1967 and a few years later in a similar Wyoming research facility. It was later discovered in wild elk and deer near those facilities in Colorado and Wyoming. Until recently, the known distribution of CWD in wild deer and elk was confined to a few hunt areas in northeastern Colorado, southeastern Wyoming, and southwestern Nebraska, but it has recently been found in new areas of these states, as well as in wild deer or elk in western South Dakota, and wild deer in northern Illinois, south-central New Mexico, northeastern Utah, south-central Wisconsin and west-central Saskatchewan. CWD also has been found in farmed elk or deer herds in Colorado, South Dakota, Nebraska, Kansas, Oklahoma, Montana, Minnesota, Wisconsin and Canadian provinces of Saskatchewan and Alberta. To date, CWD has not been diagnosed in wild or farmed deer or elk in North Dakota.

How Common Is It?
CWD is relatively rare. In Colorado, CWD infects about 1-7 percent of the deer and 0-3 percent of the wild elk in a small core area where the disease has been present for more than two decades. Nonetheless, the number of animals diagnosed with CWD has gone up in recent years. This may be largely due to the dissemination of knowledge about the disease and the increased surveillance for its occurrence.

What Wildlife Species Are Affected By CWD?
Only three species of the deer family are known to be naturally susceptible to CWD: elk, mule deer and white-tailed deer. Susceptibility of other members of the deer family (Cervidae) and other wildlife species is not known, although ongoing research is further exploring the question.

What Are The Signs Of CWD?
CWD is a slowly progressing disease; signs typically are not seen until the animal is 12-18 months of age and may take as long as 3 or more years. CWD attacks the brains of infected deer and elk, causing the animals to become emaciated, display abnormal behavior, lose bodily functions, become weak, and eventually die. Clinical signs identified include excessive salivation, loss of appetite, progressive weight loss, excessive thirst and urination, listlessness, teeth grinding, lowering of the head, and drooping ears. It should be remembered that many of these signs can be a result of other diseases.

How Is CWD Transmitted?
It is not known exactly how CWD is transmitted. Experimental and circumstantial evidence suggest infected deer and elk transmit the disease laterally (animal-to-animal). The agent may be passed in saliva, urine, and/or feces or possibly through contact with an infected facility. Although maternal transmission (from mother to offspring) may occur, it appears to be relatively unimportant in maintaining epidemics. In wild populations, decomposition of carcasses could play a role in transmission and is under investigation. CWD and other wildlife diseases seem more likely to occur in areas where deer or elk are crowded or where they congregate at man-made feed and water stations. Artificial feeding of deer and elk may compound the problem.

What Causes CWD?
The most accepted theory is that CWD is caused by a prion, an abnormal form of cellular protein that is most commonly found in the central nervous system and in lymphoid tissue. The prions cause sponge-like lesions in the animal's brain. These abnormal prions tend to accumulate only in certain parts of infected animals, i.e., brain, eyes, spinal cord, lymph nodes, tonsils and spleen. Research also indicates that prions do not accumulate in muscle tissue (meat) of deer and elk. CWD is not caused by a virus, bacteria, or nutritional imbalance.

How Do You Test For CWD?
The only sure and practical way to diagnose CWD is through microscopic examination of the brain stem of a deer or elk. Recently, research indicated that using ELISA testing on lymph nodes appears reliable as a screening method for the disease. However, immunohistochemistry testing of obex portion of brain stem remains the most reliable and accurate test available. A test for live animals, involving the removal of tonsils, is currently in experimental and research stages. Testing for CWD is done by federally-approved laboratories; there is no quick test that you or your meat processor can perform to determine if your animal has CWD.

Is There A Treatment For Infected Deer And Elk?
There is no treatment or vaccine for a deer or elk that has CWD. An animal displaying clinical signs consistent with CWD should be euthanized. Removing infected animals may help prevent spread of disease or infection.

Is CWD Transmissible To Humans?
The World Health Organization has reviewed available scientific information and concluded there is no evidence that CWD can be transmitted to humans. Researchers have found no link between the disease and any neurological disease that affects humans including the human TSE disease, Creutzfeldt-Jakob Disease (CJD). Between 1997 and 1998, three cases of sporadic CJD occurred in the U.S. in young adults. These individuals had consumed venison, which led to speculation about possible transmission of CWD from deer or elk to humans. However, review of the clinical records and pathological studies of all three cases by the Centers for Disease Control and Prevention in Atlanta, did not find a causal link to CWD.

There is no scientific evidence that CWD is transmissible through consumption of meat. The prion that causes CWD has never been found in muscle meat. The prions are, however, known to accumulate in certain parts of the infected animal- brain, spinal cord, eyes, spleen, and lymph nodes. Consumption of these parts is not recommended. Furthermore, health officials advise caution. Hunters are encouraged not to consume meat from animals known to be infected. Hunters should take common sense precautions when field dressing and processing deer or elk taken in areas where CWD has been diagnosed.

Is CWD Transmissible To Domestic Livestock?
There is no evidence that CWD can be naturally transmitted to livestock or animals other than deer and elk. Numerous experiments and investigations are currently being conducted.

What Should You Do If You See A Deer Or Elk That Looks Sick, Emaciated Or Lethargic?
Note the location and as much information as possible about the animal and situation. Call the ND Game and Fish Department at 701-328-6300, immediately. Arrangements will be made to investigate the report.

Farmed Deer and Elk

What Is The ND Department of Agriculture, State Board Of Animal Health Doing About CWD?
The ND Board of Animal Health is monitoring private, farmed elk and deer herds. The Board initiated mandatory inventory of all game farms in 1993 and initiated mandatory CWD surveillance, reporting, and testing in 1998 of any farmed elk or deer more than 12 months of age that dies from any cause. Before any deer or elk is imported into the state it must have a health certificate and a five-year risk assessment, which includes a review of the herd history.

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