Toronto Public Health (TPH) has received confirmation that three mosquito batches collected in the city of Toronto have tested positive for West Nile virus, marking the first positive findings this year. West Nile virus is transmitted to humans through the bite of an infected mosquito.
TPH conducts annual mosquito surveillance from mid-June until mid-September. Each week, 22 mosquito traps are set up across the city, which are then sent to a laboratory for identification. These mosquitoes are grouped into batches, also known as pools and tested for the virus.
While the risk of getting infected with West Nile virus in Toronto is low, TPH advises residents to take the following precautions to avoid bites from mosquitoes:
Symptoms of West Nile virus typically develop between two and 14 days after a bite from an infected mosquito and may include fever, headache, nausea, vomiting, body aches, skin rash and swollen lymph nodes. Individuals over the age of 50 or those with weakened immune systems are at greater risk of severe illness. Anyone experiencing symptoms is encouraged to contact a health care provider.
More information about West Nile virus and how to protect yourself is available on the City’s West Nile virus webpage.
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