Lambton Public Health is rolling out its yearly mosquito control effort across the county, with crews starting to treat roadside catch basins on Monday, June 8, 2026. The work targets mosquito larvae before they can grow into biting adults, aiming to cut the risk of West Nile virus for communities including Sarnia, surrounding towns, and Aamjiwnaang First Nation.
The health unit has hired Pestalto Environmental Health Services Inc. to handle the larviciding. Technicians on motorized scooters marked with slow-moving vehicle signs and MECP 2026 Applicator stickers will place a product called Methoprene (Altosid) directly into catch basins. The pellet-style larvicide is considered low-risk and works by preventing larvae from turning into adult mosquitoes.
Last year, Ontario recorded 179 human West Nile cases, though Lambton saw zero locally. The virus has been present in the area since 2002, with six lab-confirmed human cases since 2018, including one in 2024. In 2025 the contractor treated about 16,600 catch basins over three rounds. Additional monitoring will begin in early July when mosquito traps are set up and tested, with any positive findings shared publicly.
Residents can help by removing standing water from items like flowerpots, gutters, and toys, and by wearing long sleeves, pants, and socks at dawn and dusk when mosquitoes are most active. Using a repellent with DEET or Icaridin is also recommended.
