A second mosquito trap in Whitchurch-Stouffville has tested positive for West Nile virus, less than a week after the first positive result was confirmed in the community. York Region Public Health reported the new positive test on August 13, 2026, from a trap near Main Street and Tenth Line. The first positive trap, confirmed on August 7, was near Highway 48 and Aurora Road.
There are currently no confirmed human cases of West Nile virus in Whitchurch-Stouffville. Across York Region, ten mosquito traps have tested positive for the virus as of August 13, with three in Markham, three in Vaughan, and one each in East Gwillimbury, Newmarket, and Richmond Hill.
York Region Public Health is conducting environmental scans within a two-kilometre radius of the positive traps, checking for standing water where mosquitoes breed. This includes catch basins, ditches, parks, and stormwater management ponds. As part of the 2026 West Nile Virus Control Plan, larvicides are being applied to catch basins and stagnant public water sources. The larvicides used are Methoprene, Bacillus thuringiensis israelensis (Bti), and Bacillus sphaericus, all approved by provincial and federal governments.
Residents can reduce the risk of mosquito bites by removing standing water around their homes, using insect repellent containing DEET or icaridin, and wearing light-coloured, long-sleeved clothing during dawn and dusk when mosquitoes are most active. Window screens should be checked and repaired to keep mosquitoes out.
York Region’s mosquito surveillance program runs weekly from mid-June through September, with 34 traps set across the region. In 2025, York Region recorded 18 confirmed or probable human cases of West Nile virus, up from 3 cases in 2024 and 1 case in 2023.
For more information, residents can contact York Region Health Connection at 1-800-361-5653 or visit the York Region West Nile Virus page.
