Mosquitos in Toronto test positive for West Nile virus, but city says risk of infection is low

Toronto Public Health has confirmed some mosquitos in the city have tested positive for West Nile virus, but say the risk of infection is low if precautions are taken.

The findings mark the first positive cases this year after results came back on three batches of mosquitos collected in the city, the public health agency said in a news release on Friday.

West Nile virus is transmitted to humans from the bites of infected mosquitos.

Symptoms can take two to 14 days to develop and include fever, headache, nausea, skin rash and body aches.

People over the age of 50 or with weakened immune systems are at a greater risk of severe illness, said TPH.

TPH says residents should take necessary precautions to avoid mosquito bites, such as:

• Wear long, light-coloured clothing.
• Use Health Canada-approved insect repellent.
• Be cautious at dawn and dusk when mosquitoes are most active.
• Eliminate pools of water on your property, such as in planters, pool covers and waste containers.

TPH says it collects mosquitos in 22 traps across the city and tests them every week.

The city conducts annual mosquito surveillance from mid-June until mid-September.