Monitoring chronic wasting disease
We are continuing our surveillance measures to monitor wildlife for chronic wasting disease.
If you observe these signs in a wild cervid (member of the deer family), contact your local ministry work centre or email CWD@ontario.ca.
Overview
Chronic wasting disease (CWD) is a fatal and untreatable disease that affects the central nervous system of members of the deer family or “cervids”, such as:
- white-tailed deer
- American elk
- moose
- woodland caribou
CWD can severely reduce cervids populations. There is no cure and no vaccine to prevent it.
CWD is caused by infectious abnormal proteins called prions, which accumulate in the brain and other tissues leading to death. It is in the same family of diseases as:
- scrapie in sheep
- bovine spongiform encephalopathy (BSE) in cattle, also known as “mad cow disease”
- Creutzfeldt-Jakob disease in humans
CWD is highly contagious and is spread:
- through the saliva, urine, feces and blood of infected animals
- by exposure to a contaminated environment
There is evidence the disease may remain infectious in the environment, such as in soil, for years.
Take action
Prevent
What hunters can do to help keep CWD out of Ontario.
Monitor
Submit a sample to help us detect CWD as early as possible, and view your test results.
Respond
How are we preparing for a rapid and effective response to CWD detection.
Report a sick wild cervid
If you see sick wild cervid (deer, moose, elk or caribou), contact one of the following:
Natural Resources Information and Support Centre
Canadian Cooperative Wildlife Health Centre
Ministry CWD Surveillance Team
Signs of CWD
CWD is a progressive disease meaning that an infected animal may appear normal for several years before signs of illness develop.
Animals infected with CWD may exhibit:
- severe loss of body weight and body condition
- abnormal behaviour, such as indifference to human activity
- tremors, stumbling, lack of coordination or paralysis
- excessive drinking and urination
- excessive salivation or drooling
- drooping head or ears
Infected cervids may not show signs for several years. Some of these signs may be seen in other diseases.
Where CWD is found
Chronic wasting disease was originally discovered in Colorado in 1967. Since then, it has been detected in over 33 U.S. states and 5 Canadian provinces including:
- Alberta
- Saskatchewan
- Québec
- Manitoba
- British Columbia
It has been found in both provinces and all U.S. states that share a border with Ontario. CWD has also been found in South Korea and, more recently in Norway, Sweden and Finland.
Once present in wild cervids, it is very difficult to stop its spread.
We have been monitoring deer in Ontario since 2002 and tested over 15,400 samples. We have found no evidence that the disease is present in Ontario wildlife.
15,400+
surveillance samples tested since 2002
0
confirmed cases of CWD in Ontario wildlife