Toronto Public Health (TPH) has confirmed that a batch of mosquitoes collected in Toronto have tested positive for West Nile Virus (WNV). These mosquitoes are the first to test positive for WNV – an infection transmitted to people through the bite of an infected mosquito – in Toronto this year.
TPH conducts mosquito surveillance from mid-June to mid-September every year. Once a week, 22 mosquito traps are set across the city to collect mosquitoes that are then submitted to a laboratory for identification and grouped by the lab into batches to test for WNV.
While the risk of getting infected with WNV in Toronto is currently low, TPH advises residents to take these precautions to avoid bites from mosquitoes:
WNV symptoms usually develop between two and 14 days after a person is bitten by an infected mosquito. Symptoms may include fever, headache, nausea, vomiting, body aches, skin rash and swollen lymph glands. Adults 50 years of age or older and individuals with compromised immune systems are at higher risk of severe illness. Anyone concerned about symptoms should contact their health care provider.
More information about WNV and ways to reduce the risk of being infected with WNV is available on the City’s West Nile virus webpage at www.toronto.ca/west-nile-virus/.
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