Chronic wasting disease (CWD) is a fatal prion disease that affects members of the deer family (cervids), including deer, elk, moose, and reindeer. This disease has been identified in free-ranging and captive cervid populations in North America and several other countries, including Norway, Finland, Sweden, and South Korea.
CWD can affect cervids of all ages. Infected animals may remain symptomatic for months or years before developing clinical signs, including severe weight loss (wasting), stumbling, lack of coordination, listlessness, and other neurological symptoms. Some infected animals may die without exhibiting noticeable symptoms. There are currently no treatments or vaccines for CWD.
Geographic Distribution of CWD
CWD has been detected across an expanding geographic area in North America, including regions with established disease transmission in wild cervid populations. Continued monitoring of its geographic distribution is important for wildlife management, public health, and understanding potential human exposure.
CWD and Human Health
To date, no cases of CWD infection in humans have been reported. However, the potential for transmission to humans remains under investigation, particularly among individuals who hunt or consume meat from cervids in CWD-affected areas.
Because prion diseases can have prolonged incubation periods, sometimes lasting decades, continued surveillance of human prion diseases is essential for identifying potential changes in disease occurrence and detecting emerging prion diseases.
The National Prion Disease Pathology Surveillance Center (NPDPSC) works with the Centers for Disease Control and Prevention (CDC) and state health departments to support surveillance of human prion diseases, including monitoring cases from areas where CWD is endemic.
Recommendations for Hunters
To minimize potential exposure to CWD, the CDC recommends that individuals hunting in CWD-affected areas take the following precautions:
When hunting:
- Do not shoot, handle, or consume meat from deer or elk that appear sick, behave abnormally, or are found dead (road-kill).
- Check state wildlife and public health recommendations to determine whether CWD testing is recommended or required in the area. Recommendations vary by state, but information about testing is available from many state wildlife agencies.
- Strongly consider having harvested deer or elk tested for CWD before consuming the meat.
When field-dressing or processing an animal:
- Wear latex or rubber gloves when field-dressing or handling the meat.
- Minimize contact with internal organs, particularly the brain and spinal cord.
- Avoid using household knives or kitchen utensils for field-dressing.
- If using a commercial processor, consider requesting that your animal be processed individually to avoid mixing meat from multiple animals.
If your animal tests positive for CWD, do not eat meat from that animal.
Additional Resources
For additional information about chronic wasting disease, its geographic distribution, and recommended precautions, visit:
- Centers for Disease Control and Disease Prevention (CDC) - Chronic Wasting Disease
- U.S. Geological Survey (USGS) - Expanding Distribution of CWD