A neurodegenerative prion disease that affects deer has recently been found in animals in five Pennsylvania counties, the U.S. Centers for Disease Control confirmed in a statement.
Chronic wasting disease is colloquially known as “zombie deer disease” because of the effect it can have on the deer that become infected with it.
Deer in Blair, Bedford, Cambria, Clearfield and Fulton counties, which are all located in the western part of the state, have tested positive for chronic wasting disease, which was first identified in captive deer in a Colorado research facility in the late 1960s and out west in wild deer in 1981.
In addition to Pennsylvania, as of January 2019, CWD in free-ranging deer, elk and/or moose has been reported in at least 23 other states in the continental U.S., as well as two Canadian provinces, the CDC said.
“CWD is a progressive, fatal disease that affects the brain, spinal cord and many other tissues of farmed and free-ranging deer, elk and moose,” according to the CDC.
Chronic wasting disease belongs to the same family of diseases called prion diseases or transmissible spongiform encephalopathies that include bovine spongiform encephalopathy (also known as mad cow disease) and Creutzfeldt-Jacob disease and other human prion diseases in people.
“The infection is believed to be caused by abnormal proteins called prions, which are thought to cause damage to other normal prion proteins that can be found in tissues throughout the body but most often in the brain and spinal cord, leading to brain damage and development of prion diseases,” the CDC said, adding that “scientists think CWD spreads between animals through contact with contaminated body fluids and tissue or indirectly through exposure to CWD in the environment, such as in drinking water or food.”
CWD is always fatal, and as it progresses infected animals such as deer may exhibit a variety of changes in behavior and appearance, including:
- Drastic weight loss (wasting)
- Lack of coordination
- Excessive thirst or urination
- Drooping ears
- Lack of fear of people
“It is often difficult to diagnose a deer, elk, or moose with CWD based on these symptoms alone because many of CWD symptoms also occur with other diseases and malnutrition,” the CDC said, adding that “CWD does not appear to infect cattle or other domesticated animals.”
To date there have been no reported cases of CWD in humans, however to be as safe as possible and decrease their risk of exposure to it the CDC recommends that deer hunters take the following steps when hunting in areas where CWD cases have been confirmed:
- Do not shoot, handle or eat meat from deer and elk that look sick or are acting strangely or are found dead (roadkill).
- When field-dressing a deer:
- Wear latex or rubber gloves when dressing the animal or handling the deer meat.
- Minimize how much you handle the organs of the animal, particularly the brain or spinal cord tissues.
- Do not use household knives or other kitchen utensils for field dressing.
- Check state wildlife and public health guidance to see whether testing of animals is recommended or required. Recommendations vary by state, but information about testing is available from many state wildlife agencies.
- Strongly consider having the deer or elk tested for CWD before you eat the meat.
- If you have your deer or elk commercially processed, consider asking that it be processed individually to avoid mixing meat from multiple animals.
- If your deer or elk tests positive for CWD, do not eat meat from it.
The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service regulates commercially farmed deer and elk. The agency operates a national CWD herd certification program. As part of the voluntary program, states and individual herd owners agree to meet requirements meant to decrease the risk of CWD in their herds. Privately owned herds that do not participate in the herd certification program may be at increased risk for CWD.
The PA Game Commission has established Disease Management Areas (DMAs) to help combat the spread of chronic wasting disease in deer and other animals affected by it.
“Within DMAs, rehabilitation of cervids (deer, elk and moose); the use or possession of cervid urine-based attractants in an outdoor setting; the removal of high-risk cervid parts; and the feeding of wild, free-ranging cervids are prohibited,” the Game Commission said. “Increased testing continues in these areas to determine the distribution of the disease. Newly confirmed cases alter the boundaries of DMAs as the Game Commission continues to manage the disease and minimize its effect on free ranging cervids.”