Chronic Wasting Disease (CWD) is an untreatable and fatal brain and nervous system disease found in deer, elk and moose.
Prions: The Contagious Agent
Abnormal shaped proteins, named "prions," are documented as the cause of CWD. When a prion enters an organism, it causes existing, healthy proteins to convert into diseased, misfolded proteins.
Prions accumulate in tissues of the brain, eyes, tonsils, spleen, lymph nodes, intestinal tract and spinal cord.
Prion-type diseases, such as CWD, scrapie in goats and sheep, mad cow disease in cattle and Creutzfeldt-Jacob disease in humans are known as "transmissible spongiform encephalopathies" (TSE) diseases. While CWD is similar to these diseases, it has a uniquely shaped prion that only affects deer, elk and moose.
How CWD Spreads
- CWD prions are shed through saliva, urine and feces of infected animals. A healthy deer, elk or moose can pick up the disease by direct contact with the infected animals body fluids or by eating contaminated sources of food or water.
- CWD prions bind with soil particles and remain infectious in the environment for up to 18 years or more, with the ability to infect future generations of deer, elk or moose.
- Movement of living or dead infected animals increases the range of the disease. Infected animals can be moved by commercial big game farmers or by hunter-killed carcasses. Scavengers like coyotes and crows can also spread CWD prions over a greater area.
Find out how you can help prevent the spread of CWD to protect our valuable wild deer herds.
Signs of Infection
An infected animal does not always look sick when it has CWD. The slow attack on the brain and nervous system may take several months to several years before the animal shows signs of infection, such as:
- loss of bodily functions
- extreme thirst
Note: Some signs are not unique to CWD and can occur with other for other reasons, such as chronic lung abscesses, brain abscesses or injuries from a motor vehicle collision.
Diagnosis and Testing
Annually DEC collects 2,000 samples of brain tissue and lymph nodes from hunter-killed wild white-tailed deer and submits them to a federally approved laboratory for prion testing. Learn more about DEC's CWD surveillance and monitoring.
In New York: CWD was first discovered in captive and wild deer in Oneida County in 2005. Since then, no new cases of CWD have been found. Read more on the status of CWD in New York.
Elsewhere: To date, wild or captive deer, elk and moose have been infected by CWD in the following states and provinces:
|State or Province||Wild
Impact to Human Health
CWD is not known to infect humans at this time, but the following precautions are advised when handling, processing and eating big game meat.
Handling, Processing and Eating Big Game Meat
- Wear rubber gloves when field dressing and processing animals.
- Minimize the handling of brain and spinal tissue.
- Sanitize hands and instruments thoroughly after field dressing. Soaking hard surfaces and metal tools for one hour at room temperature in a 50% solution of household bleach and water will inactivate CWD prions.
- Avoid consuming the brain, spinal cord, eyes, spleen, tonsils, intestinal tract and lymph nodes of harvested animals. Normal field dressing, coupled with boning out a carcass, will remove most, if not all, of these body parts. Cutting away fatty tissue will remove remaining lymph nodes.
- Bag and dispose of remaining carcass parts in the trash or a municipal landfill.
Videos on how to properly and safely process a deer are available on the Chronic Wasting Disease Alliance website (see "Links Leaving DEC's Website" in the right-hand column at the top of this page).