TORONTO (Reuters)
- The deadly mosquito-borne West Nile virus, responsible for killing
about 10 people in North America in the past year, may have found
its way to Canada, an infectious disease expert said on Monday.
Dr. Andrew
Simor, head of the Department of Microbiology at the Sunnybrook
and Women's College Health Sciences Center in Toronto, said the
virus was found recently in dead birds in upstate New York near
the Canadian border, leading health officials to believe it had
likely made its way to Canada.
The virus,
first discovered in North America last summer in New York City,
is passed by mosquitoes from birds to humans.
``It certainly
raises the possibility that at least birds across the border may
have become infected,'' Simor said. ''Birds fly across the border
without recognizing national boundaries.''
Although considered
rare, the concern prompted Canadian health officials last week
to issue notices to health units to gather dead birds for tests.
The virus,
which killed seven people in the New York metropolitan area last
summer, is spread to humans by the bite of an infected mosquito,
and can cause encephalitis or meningitis. It is not transmitted
from human to human, or from birds to humans.
Most infected
people do not experience symptoms, but in elderly or other vulnerable
individuals such as those with weak immune symptoms, West Nile
can be potentially fatal. The symptoms include fever, headaches,
change in consciousness and seizures.
There has
been only one reported death in Canada. Last year a 75-year-old
Toronto man died after apparently contracting the virus during
a visit to New York City.
``I think
overall the risk is very, very low. In the past two years there
has only been a dozen confirmed cases in New York and Boston,''
Simor said. ``To my knowledge there has been no known case (contracted)
in Canada.
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