Manitoba Health, Seniors and Long-Term Care has issued a ministerial order under the Environment Act to spray for adult mosquitoes with DeltaGard 20EW in affected communities due to risk of exposure to West Nile virus. High temperatures across southern Manitoba have shortened the time required for West Nile virus to develop within infected Culex tarsalis mosquitoes and be transmitted to humans. Surveillance data from last week showed high numbers of adult Culex tarsalis mosquitoes and evidence of infection with West Nile virus. To date, there have been no human cases of West Nile virus confirmed in Manitoba in 2026. For more information on West Nile virus in Manitoba, including surveillance data, prevention tips and symptoms of infection, visit gov.mb.ca.