Chronic Wasting Disease
What is Chronic Wasting Disease (CWD)?
CWD is a neurological (brain and nervous system) disease of deer and elk, caused by an abnormal form of a protein called a prion. The slow accumulation of abnormal prions in the brain and lymphatic tissues ultimately results in death. The disease belongs to a family of diseases known as transmissible spongiform encephalopathy (TSE). While CWD is similar to mad cow disease in cattle and scrapie in sheep, there is no known relationship between CWD and any other TSE of animals or people. In deer and elk there is no practical test of live animals to detect CWD and there is no known cure.
How is it spread?
It is not known exactly how CWD is spread. Experimentally, the infectious agent can be spread directly (animal to animal contact) and indirectly (soil or other surface to animal). It is thought that the most common mode of transmission from an infected animal is via saliva, but feces, urine and possibly other body secretions also contain the prion. There is evidence that people moving live infected animals have spread the disease over long distances.
Is it dangerous to humans?
There currently is no evidence that the agent of CWD affects humans. However, public health officials recommend that human exposure to the CWD agent be avoided as they continue to research the disease. This includes not eating meat from known infected animals, or animals that appear sick, and avoid eating the brain, spinal cord, eyes, lymph nodes, spleen, and tonsils where the abnormal prion accumulates.
Where has it been found?
As of June, 2015, CWD is known to infect free-ranging deer and elk in portions of Colorado, Illinois, Iowa, Kansas, Maryland, Michigan, Minnesota, Missouri, Nebraska, New Mexico, New York, North Dakota, Pennsylvania, South Dakota, Texas, Utah, Wisconsin, Virginia, West Virginia, Wyoming, and Alberta and Saskatchewan, Canada. In addition, CWD has been found in captive/farmed elk and white-tailed deer in Colorado, Iowa, Kansas, Michigan, Minnesota, Missouri, Montana, Nebraska, New York, Ohio, Oklahoma, Pennsylvania, South Dakota, Wisconsin, and Alberta and Saskatchewan, Canada.
Where in West Virginia?
CWD has been found in 179 white-tailed deer in Hampshire County and four deer in Hardy County. Three of the positive deer were road-killed, the first CWD positive deer in WV detected in 2005 and others in 2008 and 2011. One hundred eleven (111) positive deer were hunter-harvested, one in 2006, six in 2007, six in 2008, 15 in 2009, 10 in 2010, 9 in 2011, 16 in 2012, 29 in 2013 and 19 in 2014. The remaining 69 positives were collected by West Virginia Division of Natural Resources (WVDNR) personnel in cooperation with local Hampshire County landowners to monitor the disease. Since 2002, the WVDNR, Wildlife Resources Section, in cooperation with the SE Cooperative Wildlife Disease Study at the University of Georgia and the Minnesota Veterinary Diagnostic Laboratory has tested 15,504 deer from West Virginia for CWD and as of June, 2015, the 183 deer are the only animals found thus far to have the abnormal prion associated with CWD. The Virginia Department of Game and Inland Fisheries has detected 9 positive deer in Frederick County and one deer in Shenandoah County, east of the Hampshire County and Maryland Department of Natural Resources has detected six positive deer in Allegany County north of the Hampshire County.
What is being done about CWD in WV?
CWD in West Virginia represents a significant threat to the state's white-tailed deer. The disease does not produce an immediate widespread die-off of deer but if allowed to spread will cause long-term damage to the herd. Those that have tried to predict the outcome of the disease on a deer population have described the disease as a 30 to 50 year epidemic. Due to the uncertain ramifications that CWD may have on the white-tailed deer resource in West Virginia, the WVDNR is taking actions to gather more information on the prevalence and distribution of the disease in the area surrounding the known infected deer. This goal will be accomplished by increasing the number of deer tested with the help of other state and federal agencies, deer hunters, and local landowners. Because of the many scientific uncertainties regarding the basic biology and ecology of CWD, there are no proven solutions to combating CWD once present in free-ranging deer. However, baiting and feeding deer is known to increase the spread of diseases transmitted directly from deer to deer. In addition, experiments with heavily infected mule deer carcasses in close quarters with live mule deer have produced infections, thus restrictions on the disposal and transport of deer carcasses have been implemented in Hampshire, Hardy, and Morgan counties and baiting and feeding of deer has been banned in Berkeley, Grant, Hampshire, Hardy, Jefferson, Mineral and Morgan counties (see cross hatch area on map). Other management actions will be adaptive and based on the findings of future surveillance and research.
How can you tell if a deer has CWD?
Infected animals may not show any symptoms of the disease for a long period. In later stages of the disease, infected animals begin to lose control of bodily functions and display abnormal behavior such as staggering or standing with very poor posture and lose fear of humans. Infected animals become very emaciated (thus wasting disease), appear in very poor body condition, and often stand in or near water and drink excessively. Drooling or excessive salivation may be apparent. However, these symptoms are not unique to CWD and are also characteristic of diseases other than CWD.
What Can Hunters Do?
- If you kill a severely emaciated (very skinny) deer or a deer that is obviously sick contact the WVDNR Wildlife Resources Section office nearest you.
- Don't feed or bait deer. These practices concentrate deer, increase the likelihood of spread of any disease present in the deer herd, and may introduce foreign contaminates via the feed or bait.
- Harvest adequate numbers of antlerless deer to maintain deer populations in balance with natural food supplies. A deer population in balance with available habitat is healthier and better able to fight diseases.
- Use caution in spreading urine based lures in the environment and do not place deer urine lures on the ground or on vegetation where deer can reach them.
- If you plan to hunt deer or elk in a state known to harbor CWD follow that state's rules on removing animals from the area. Bring back only boned out meat or quarters and thoroughly cleaned skull plates and antlers. This applies to Virginia's CWD containment area and Maryland's and Pennsylvania's CWD disease management areas.
- If you deer hunt in Hampshire, Hardy and Morgan counties, please see special WV regulations regarding carcass transport in the Hunting and Trapping Regulations Summary or online at www.wvdnr.gov. Also, please cooperate with WVDNR requests for information and samples needed for CWD testing.
- If you observe live deer or elk being transported in a truck or trailer notify your local DNR office as soon as possible.
- If you kill a cervid (deer, elk, etc.) out-of-state in a fenced enclosure only boned out meat or quarters and thoroughly cleaned skull plates and antlers may be transported into WV.
Chronic Wasting Disease Alliance www.cwd-info.org