West Nile virus confirmed in Toronto, Canada's first human lawsuit this year

Canada's public health agency says the first human case of the West Nile virus this year has been acquired domestically. It has been confirmed in Toronto.

The confirmation comes after Toronto Public Health said that the first laboratory confirmed cases of the virus in 2025 were adult residents of cities with no travel history.

This virus is transmitted to humans through infected mosquitoes.

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PHAC's West Nile Surveillance Report states that as of July 12, two other Canadian residents were infected while traveling abroad this year.

That surveillance map shows detection of two mosquito pools in Ontario and the West Nile in Manitoba as of that day.

Public Health in Toronto says symptoms usually begin 2-14 days after being bitten by a mosquito and can include fever, headache, nausea, vomiting, body pain, skin rash, swelling lymph glands or stiff neck.

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Elderly people and those with compromised immune systems say they are at higher risk for severe illness.

People can avoid mosquito bites to prevent infection – wear light colored long sleeves and long pants, use Canadian approved insect repellents, place tightly fitted screens on all windows, remove sturdy water with buckets, plans, pool covers and other containers, and eliminate mosquito breeding grounds.