Chronic Wasting Disease
Chronic Wasting Disease (CWD) is a fatal disease of animals in the Cervid family, which include mule deer, white-tailed deer, elk and moose. It affects the central nervous system.
CWD belongs to a group of diseases known as transmissible spongiform encephalopathies (TSEs). These diseases are caused by an abnormal protein called a “prion”. Other diseases in the TSE family include
- Bovine spongiform encephalopathy (BSE or “mad cow”)
- Scrapie in domestic sheep and goats
- Creutzfeldt-Jakob disease in humans
Fast Facts About Chronic Wasting Disease (CWD)
- CWD is a “prion” disease that affects the central nervous system.
- Only animals in the deer family (also called Cervids) can be infected with CWD. There is no evidence that humans can get CWD.
- CWD has been found in mule deer, white-tailed deer, elk and moose. CWD is not believed to be transmitted to other kinds of wild or domestic animals by natural means.
- A deer or other animals in the Cervid family can be infected with CWD when it contacts an infected animal, infected tissues (carcasses), or CWD-contaminated soils.
- CWD is always fatal. There is no treatment or vaccine.
- CWD is not a naturally occurring disease.
- CWD has not been found in B.C. yet. But we need to be vigilant, and continue to survey for the disease (collect more samples).
- Once CWD is established in an area, there is no known method to contain and manage it. Prevention is the key!
How is Chronic Wasting Disease Transmitted?
New animals are infected with chronic wasting disease (CWD) when they are exposed to prions in
- Saliva, urine or feces from CWD-infected animals
- A contaminated environment, such as prions in soil or vegetation
Transmission rates increase when there are a lot of animals in one place, or when animals share water or food.
Prions may also be transported by plants, through the air or when scavengers eat the carcasses of infected animals. However we do not fully understand whether or how deer and other Cervids can be infected with CWD in these ways.
Is There a Risk to Humans?
There is no evidence that chronic wasting disease (CWD) can infect humans. However, there are recommended guidelines to keep people safe from the possibility of infection:
- Only harvest and eat animals that appear healthy
- Wear latex or rubber gloves when field dressing or handling any dead animal
- Wash hands and equipment thoroughly after field dressing is completed
- Do not consume the meat from any deer or other Cervid that has tested positive for CWD
What are the Symptoms of Chronic Wasting Disease?
Symptoms may not appear for years after infection, and newly infected animals can appear normal. Signs seen in chronic wasting disease (CWD)-infected animals include
- Weight loss
- Drooling, difficulty swallowing
- Poor coordination, stumbling
- Depression, trembling
- Increased drinking and urination
Is Chronic Wasting Disease Present in British Columbia?
The B.C. Chronic Wasting Disease (CWD) Surveillance Program has tested over 2500 deer, elk and moose (2002 to 2013). No animals tested in B.C. so far have had CWD. B.C. is still considered to be at low risk. However, CWD is spreading west in free-ranging deer in Alberta. We must continue to monitor the health of our wild deer species.
Where did Chronic Wasting Disease Come From?
Chronic wasting disease (CWD) was first detected in captive mule deer in the 1960s in Colorado and Wyoming. CWD was introduced to Canada from the United States by imported captive elk. It was found in free-ranging mule deer in Saskatchewan in 2001 and in Alberta, near the Saskatchewan border, in 2005. CWD has been diagnosed in captive and free-ranging Cervids in 18 U.S. states and two Canadian provinces.
- See the current distribution
What is the Risk of Chronic Wasting Disease Entering B.C.?
The biggest risk of CWD entering B.C. is through chronic wasting disease (CWD)-infected carcasses. If an infected carcass is brought to B.C., there is a high risk that CWD will be passed to animals here. The CWD prions can attach to soil and infect new animals. A B.C. Wildlife Act Regulation, passed in 2010, prohibits the import of intact deer, elk or moose carcasses harvested anywhere outside of B.C. unless all “risky tissues” have been removed.
B.C. CWD Wildlife Act Regulation
Before bringing deer or other Cervid meat or parts into B.C., you must prepare the carcass in the following way:
- Remove the head, hide, hooves, mammary glands, all internal organs and spinal column at the kill site. Leave these parts there—do not move them from the kill site.
- Debone meat before you leave the kill site.
- Remove antlers and bone plate from the remainder of the skull. Treat the bone plate and antler bases with a solution of 2% chlorine (bleach).
- Remove cape/hide and seal in a waterproof container to ensure that no fluids, tissue or hair can escape.
The B.C. Chronic Wasting Disease (CWD) Program
The B.C. Chronic Wasting Disease (CWD) Program focuses on CWD prevention, outreach and surveillance. To reduce the risk that CWD will be introduced to B.C, the CWD Program has launched a public awareness campaign that includes
- Highway signs at the Alberta border
- Reminders to hunters not to bring deer carcasses back to B.C.
We encourage hunting communities to participate in outreach and surveillance programs. The CWD Program asks hunters to voluntarily submit heads they have harvested. We also encourage anyone to submit the heads of road-killed deer, elk and moose, or to reports sightings of those that are thin or sick from anywhere in the province. Those from the Peace and East Kootenay areas are of the highest priority as these areas are most at risk.