Durham Health Department to start 2026 West Nile surveillance program May 11
The Durham Region Health Department will begin its 2026 West Nile virus (WNV) surveillance and control program between May 11 and June 8, according to a regional notice posted April 15. The program will include monitoring for larval mosquito activity, applying larvicide in catch basins and surface water sites, and trapping adult mosquitoes for WNV testing across Durham Region.
The health unit reported 21 human cases of West Nile virus in 2025, along with 26 mosquito batches that tested positive for WNV through its adult mosquito trapping program.
West Nile virus spreads to humans through the bite of an infected mosquito and does not spread person to person.
As part of this year’s program, the Health Department will no longer mail request forms to private property owners for larviciding of catch basins on private property. The department said requests will be submitted online instead.
The Health Department’s notice also outlined steps residents can take to reduce stagnant water around their homes, including draining standing water from items such as pools, bird baths and planters; clearing roof gutters; and covering or treating rain barrels.
The department also advised residents to reduce mosquito bites by wearing long sleeves and full-length pants at times when mosquitoes are most active, using insect repellent containing DEET or picaridin, and making sure door and window screens fit properly.
The Health Department did not provide dates or locations for larvicide applications or mosquito trapping during the May 11–June 8 period.