Chronic Wasting Disease (CWD)

What is chronic wasting disease?

CWD is a deadly disease that can spread in deer, elk, and moose populations. CWD damages portions of the brain and typically causes progressive loss of body condition, behavioral changes, excessive salivation (drooling), and death. The cause of the disease is suspected to be a type of prion (protein infectious particle) that is found in some tissues of infected animals.

Are prion diseases transmissible to humans?

Although there is considerable ongoing research, there is no confirmed human neurologic (nervous system) disease linked to CWD at this time. In addition, there have never been any indications of human illness related to scrapie, a prion disease found in sheep. However, eating meat from cows infected with a different prion disease, bovine spongiform encephalopathy (BSE), in other countries appears to be related to human deaths from a variant of a previously identified neurologic disease, Creutzfeldt-Jakob disease (vCJD).

Where is CWD found?

CWD has spread widely in North America in wild deer and elk over the last two decades. It has been found in more than half of U.S. states, as well as Canada and other countries. This map shows where CWD has been found in deer, elk, and moose.

How is CWD spread?

  • Infected animals transmit the disease through animal-to-animal contact and/or contamination of feed or water sources with saliva, urine, and feces of infected animals.
  • Soil and plants can also be contaminated with CWD prions when infected animal carcasses decay as well as from feces or urine from infected animals. Prions can stick to soil and plants and continue to spread in the environment for years.
  • Infected animals can also spread CWD as they move to other areas.
  • Scavengers like coyotes and crows that feed on infected remains can also spread CWD prions over a larger area in their feces.
  • Hunters who use natural deer urine-based lures could also spread CWD prions.

How soon after CWD exposure do signs of infection appear?

CWD has a long incubation period and typically takes at least 16 months for an infected animal to show signs of illness. Infected animals do not show signs of illness until they have been infected for several months.

Are domestic animals at risk for CWD?

So far, there has been no evidence that CWD is a threat to domestic animals or livestock other than deer or elk, and there have been no reports of CWD in dogs or cats.

Are there health risks for hunters in handling deer or elk?

There is no evidence to date that hunters are at risk of getting CWD. However, hunters could bring CWD prions into New York without realizing it. Hunters should observe normal precautions around any animals, such as avoiding sick or strange-acting animals. No one should knowingly eat meat from an infected animal. Hunters should take precautions when handling, processing, and eating big game meat.

Depending on how an animal is handled, there may be a risk of other diseases including rabies. They must report to their local health department any potential rabies exposures such as an animal bite, or contact between a person's eyes, nose, or mouth (mucous membranes) or a fresh, open wound with the animal's saliva, brain, or other nervous tissue.

What should you do if someone sees a sick deer, elk, or moose?

Contact your nearest DEC regional wildlife office or Environmental Conservation Officer to report a deer that appears sick, unusually thin, or behaves abnormally. Check for signs like:

  • Appearing weak or thin
  • Disorientation
  • Loss of bodily functions
  • Extreme thirst
  • Death

Because a sick deer or elk could have rabies, if there has been contact between a person's eyes, nose, or mouth or a fresh, open wound with the animal's saliva, brain, or other nervous tissue, the animal must be reported to the local health department. After the animal has been humanely euthanized, the local health department will send the head to the New York State Department of Health Rabies Laboratory for rabies testing. Animals that are negative for rabies will be submitted for subsequent CWD testing.

What precautions should you take for handling, processing, or eating meat from deer or elk?

To minimize the risk of transmission of any infectious diseases when handling or processing animals, the following precautions are recommended:

  • Do not handle or eat deer or elk that appear to be ill or found dead.
  • Wear rubber or latex gloves when handling or processing carcasses.
  • Avoid handling or cutting through the skull or spinal cord. Use separate dedicated knives, saws and cutting boards to butcher deer, particularly if you cut through the spinal cord or skull (such as when removing antlers). Do not use regular kitchen utensils. Wash thoroughly with soap and water any knives, butchering tools, work surfaces, hands, and any other part of the body that has been exposed to animal tissues, blood, urine, or feces. Equipment should then be rinsed with boiling water or sanitized with a chemical sanitizer.
  • Soak cleaned knives and tools for one hour in a fresh solution of household chlorine bleach (unscented) mixed with an equal amount of water (e.g., one quart bleach with one quart of water – a 50 percent solution), air dry, then rinse with clean water. Wipe down cleaned counters and other surfaces with 50 percent bleach solution and allow them to air dry. If bleach contacts eyes, skin, or clothing, immediately wash affected area with water and remove affected clothing. Make sure that enough fresh air is available because bleach may cause eye, nose, or throat irritation.
  • Make sure to thoroughly clean the skull cap, utensils, and work surfaces with bleach solution as described above.
  • Avoid handling brain or spinal tissues or fluids, saliva and mouth parts and wash hands thoroughly with soap and water afterward if such handling occurred. If these tissues or fluids get into a fresh open break in a person's skin or the eyes, mouth, or nose, contact the local health department to evaluate possible rabies exposure and need for testing the animal for rabies.
  • Request, if possible, that individual animals are processed individually, without meat from other animals being added together.
  • Have deer boned out and have as much fat, connective tissue, and lymph nodes removed as possible. Minimize handling brain and spinal tissue. The brain, spinal cord and other nervous tissue, spleen, pancreas, eyes, tonsils and lymph nodes of deer, elk, and moose may have CWD prions, and additional organs (liver, kidney, heart and salivary glands) may pose a risk of infection for a number of diseases. Normal field dressing will eliminate most of these organs and tissues.
  • Bag and throw out remaining carcass parts in the trash or municipal landfill.
  • Do not consume, distribute, or donate for human consumption a known or suspect CWD-positive animal.

For more information about handling, processing, or eating meat from deer or elk in other states, contact the state agriculture, wildlife, and health agencies.

Are there any risks from deer waste or products?

Although there is no indication of human infection due to contact with deer waste or products related to CWD-infected deer or elk, follow these precautions as general prevention for multiple diseases:

  • Avoid contact with animal bodily waste material and clean up animal waste from areas frequented by children.
  • If there is skin contact with animal waste, wash the area with soap and water immediately.

How is CWD diagnosed?

While apparently healthy animals might be infected, eventually infected animals will develop signs of illness. Definitive diagnosis for the disease currently requires laboratory testing of the brain and/or lymph nodes.

Can a specific deer or elk be tested?

There is ongoing CWD surveillance in New York State. Consult the NYS Department of Environmental Conservation (see website link below) for more information on CWD testing of deer in New York State.

Where is there additional information about CWD?

More information about CWD is available from the following state and federal agencies: