York Region Public Health has confirmed that a mosquito trap near Highway 48 and Aurora Road in Whitchurch-Stouffville has tested positive for West Nile virus. This is the first detection of the virus in local mosquitoes this season.
The public health agency is conducting an environmental scan within a two-kilometer radius of the positive trap, focusing on identifying and treating standing water containing mosquito larvae on public property, including catch basins, ditches, parks, and stormwater ponds.
As of August 7, 2026, there are eight positive mosquito traps across York Region, including two in Markham and Vaughan, and one each in East Gwillimbury, Newmarket, Richmond Hill, and Whitchurch-Stouffville. No human cases of West Nile virus have been reported in York Region this year. However, Toronto Public Health confirmed the city’s first human case of the virus on July 30.
Residents are advised to remove standing water from their properties, use insect repellent containing DEET or icaridin, and wear long-sleeved clothing during dawn and dusk when mosquitoes are most active. York Region monitors 34 mosquito traps weekly from mid-June until the end of September as part of its West Nile virus surveillance program.
This is the first time Whitchurch-Stouffville has had a positive mosquito trap since at least 2024. York Region’s 2025 human case count of 18 was the highest in recent years, up from three in 2024, while Ontario recorded 172 human cases last year.
Residents can report standing water or get more information by contacting York Region Health Connection at 1-800-361-5653.
