Public health begins regular mosquito larvicide program

Program aims to reduce mosquito populations suspected of carrying West Nile virus

WELLINGTON COUNTY – The local health unit has begun its regular mosquito larvicide program.

Wellington-Dufferin-Guelph Public Health (WDGPH) announced the start of the program, which will run until early October, in a press release on May 19.

“Mosquitos are more than just a spring and summertime annoyance,” stated Dr. Nicola Mercer, Medical Officer of Health and CEO of WDGPH.

“Some species may carry the West Nile virus which, if transmitted to humans, may cause flu-like symptoms and in rare cases, inflammation of the brain or spinal column can occur which may result in permanent disability or death.

“By proactively treating areas of standing water on municipal property, we’re helping to prevent these areas from becoming sites for mosquitoes to breed.”

Public health officials say trained technicians apply larvicide by hand in areas of standing water in Wellington and Dufferin counties, helping to reduce or eliminate mosquito populations known to carry West Nile virus.

“In 2021, there was one confirmed human case of West Nile virus, and two cases in birds, identified in Wellington-Dufferin-Guelph,” officials say.

The larvicide will be applied in mosquito larvae breeding sites, such as:

  • roadside ditches;
  • temporary pools;
  • sewage lagoons;
  • storm-water retention ponds;
  • areas of standing water; and
  • municipal catch basins.

Public health is encouraging property owners to remove standing water anywhere it tends to collect, including flowerpots, bird baths, wheelbarrows, eaves troughs, rain barrels and tires.

Officials say residents can reduce the risk of mosquito bites and potential exposure to West Nile virus by wearing light-coloured pants and long-sleeved shirts, avoiding the outdoors at dawn and dusk when mosquitoes tend to feed and using a mosquito repellent with DEET or Icaridin.

For information about the products used in the larvicide program, or details on treatment locations, call the Canadian Centre for Mosquito Management at 1-855-220-7022.

To have a catch basin on your property treated at no cost, call public health at 1-800-265-7293 ext. 4753.

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