The general public should be alert to unusual deaths in wild birds - particularly crows, ravens, magpies, and jays. Such deaths may indicate that West Nile Virus, first recognized in North America in 1999, is active in the area.
Crow-family birds have shown to be particularly sensitive to West Nile Virus and have high death rates if infected. Evidence suggests that crow die-offs precede an increased risk for human illness by 2 to 6 weeks. Monitoring of dead crow-family birds can provide an early warning signal that West Nile Virus is active in an area.
In 2011, one Canadian jurisdiction, British Columbia, will be conducting an active dead bird surveillance program for West Nile Virus. Other forms of surveillance, including mosquito and larval testing, blood screening as well education programs and the use of temperature and habitat data continue to be utilized to assess the level of risk to West Nile Virus. In addition, the public is encouraged to report all forms of wildlife found dead, including wild birds, especially unusual mortality events. Reports should be directed to your local authority responsible for wildlife or directly to the Canadian Cooperative Wildlife Health Centre. All forms of dead wildlife can be submitted to the CCWHC as part of ongoing disease surveillance.
Wildlife disease surveillance is a cooperative effort of several government and non-government organizations. The goal of this program is to reduce the risk of human infection through public education and mosquito abatement if, when, and where the situation warrants such action. The dead corvid surveillance program is a part of this organized effort.
CCWHC Alberta - Calgary
CCWHC Western/Northern - Saskatoon
CCWHC Ontario/Nunavut - Guelph
CCWHC Quebec - Montreal
CCWHC Atlantic - Charlottetown
B.C. Animal Health Centre - Abbotsford