June 2002
Contact: Jerry Nelson
(360) 902-2519
WDFW Public Affairs
(360-902-2250)

What is chronic wasting disease?

Chronic wasting disease (CWD) is a disease of the central nervous system found in deer and elk. It is one form of transmissible spongiform encephalopathy (TSE). TSEs are infectious diseases of humans and animals that are caused by a deterioration of brain tissue. These diseases are progressive and always fatal. Other TSEs currently known to science include scrapie in domestic sheep, bovine spongiform encephalopathy (BSE) in cattle, kuru in humans, and Creutzfeldt-Jacob disease in humans.

Has CWD been found in Washington wildlife?

No. To date, there have been no confirmed cases of CWD in Washington deer or elk.

Where has CWD been found?

Chronic wasting disease was first identified in captive deer in Colorado in 1967 and since has been found in wild and/or captive deer and elk in parts of at least seven other states (Montana, Wyoming, South Dakota, Kansas, Nebraska, Oklahoma and Wisconsin) and two Canadian provinces, (Alberta and Saskatchewan).

Can humans or domestic animals become infected with CWD?

To date, there have been no confirmed cases of CWD being transmitted to humans or passed to domestic animals or livestock.

Is the Washington Department of Fish and Wildlife monitoring wildlife for CWD?

Yes. The Washington Department of Fish and Wildlife (WDFW) has been testing deer and elk for CWD since 1995. Last fall WDFW tested over 700 deer and elk for CWD. Recently, the Department secured $180,000 in special funding from the Legislature to increase and broaden testing for CWD and other wildlife diseases. This fall WDFW staff plans to increase sampling to 900 animals, focusing on areas where few or no samples have been collected. To date, none of the samples collected have tested positive for CWD.

What is being done to minimize the risk of CWD?

Washington is considered a low-risk state for CWD because it is not adjacent to areas where the disease is endemic, and because the state took action a decade ago to curtail game farming, including banning the importation of live deer, elk and other cervids from species that are native to Washington. That rule [Washington Administrative Code (WAC) 232-12-064], enacted in 1993, was an important step in reducing the risk of introducing CWD or other diseases into wild animal populations in this state.

In 1995 WDFW began targeted CWD surveillance sampling, meaning that samples were collected from deer and elk that died or were harvested after exhibiting symptoms similar to those associated with CWD. None of those samples tested positive for CWD.

In the 2001 hunting season, CWD testing efforts were broadened to sample harvested deer and elk around the state at hunter check stations and from road-kills. Plans call for testing more hunter-harvested animals in the coming 2002 fall hunting season, focusing on areas where few or no samples have been previously collected.

Currently, staff from WDFW, the state Department of Health and the state Department of Agriculture are working together to educate the public on CWD and to develop strategies aimed at minimizing the risk of CWD here.

On the federal level, the U. S. Department of Interior and the U. S. Department of Agriculture have formed a joint committee to develop a unified federal plan for combating CWD. Specifically, federal officials are putting plans in place to increase tracking of herds and mapping of CWD cases, develop better diagnostic tests and continue research on how the disease spreads.

How are animals tested for CWD?

Tests to confirm CWD are done in the laboratory, using brain stem tissue taken from dead animals. Therefore, the best sources for test subjects are hunter-harvested and road-killed deer and elk. WDFW personnel collect samples from harvested animals through hunter check stations, field patrols and locker checks. The success of testing efforts relies on the cooperation of hunters in allowing samples to be taken from their harvested animals. To date, no CWD screening test is available for live animals, although research is underway elsewhere to develop one.

How is CWD transmitted?

The mode of transmission is unknown at this time. It is suspected that the disease may be transmitted by animal-to-animal contact and/or contamination of feed or water with saliva, urine or feces from infected animals. There is currently no evidence that CWD can be transmitted to humans, domestic livestock or wildlife other than deer or elk.

What are the symptoms of CWD?

Animals with CWD exhibit excessive weight loss, appear uncoordinated and lethargic with their heads down and ears drooping, salivate excessively, drink more water than usual and isolate themselves from other animals. Eventually the afflicted animals die.

Should hunters take precautions against CWD?

Although CWD has never been documented in Washington, and there currently is no scientific evidence of CWD being transmitted from deer or elk to humans, it is advisable for hunters to exercise caution when handling deer and elk. Appropriate precautions include:

• Avoiding harvesting any animal that appears sick or is behaving strangely
• Wearing rubber gloves while field dressing deer and elk
• Avoiding consuming the brain, spinal cord, eyes or spleen or lymph nodes of harvested animals.

One important way hunters can assist in CWD monitoring here is to cooperate with disease-testing efforts at field check stations.

Related websites:

• U.S. Geological Survey National Wildlife Health Center
• U. S. Department of Agriculture
• Chronic wasting disease information from the Western Association of Fish & Wildlife Agencies and the Western Wildlife Health Cooperative
• Nebraska Game and Parks updates on CWD-control efforts nation-wide
• Colorado Division of Wildlife

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