The Manitoba government is issuing a ministerial order under the Environment Act to begin spraying for adult mosquitoes with DeltaGard 20EW® because of high numbers of adult Culex tarsalis mosquitoes and evidence of mosquito infection with West Nile virus (WNV). The order will cover the City of Winkler.

Subject to weather and site conditions, adult mosquito control will take place in the areas of, but not limited to, the City of Winkler plus an approximately three kilometres extended zone around the city. This extended zone includes the communities of Reinfeld, Chortitz and Schanzenfeld.

Adult mosquito control occurs in the evening and at night and is expected to begin the evening of Thursday, Aug. 1, weather conditions permitting. The treatment times and area map will be available at gov.mb.ca.

Public health officials note that wet conditions early in the season and recent hotter, drier weather have created ideal conditions for Culex tarsalis mosquitoes that can spread the West Nile virus. The risk for potential human exposure to WNV at this time is high in the Southern Health-Santé Sud region, and this will likely continue during the historical high-risk period (mid-July to mid-August). At this time, no locally acquired human cases of WNV have been confirmed in Manitoba.

While Manitobans are encouraged to enjoy warm weather outdoor activities, it is strongly recommended to reduce the risk of mosquito bites and potential exposure to the virus. Key prevention measures include:

  • reducing the amount of time spent outdoors during peak mosquito hours between dusk and dawn;
  • using an appropriate mosquito repellent;
  • wearing light-colored, loose-fitting clothing with long sleeves and pant legs;
  • maintaining door and window screens; and
  • cleaning and emptying yard items that collect water.

Approved by Health Canada for use in 2017, DeltaGard 20EW® is classified as a reduced-risk pesticide. When applied using ultra-low volume methods and as per label directions, DeltaGard 20EW® is unlikely to affect human health.

However, individuals can minimize their exposure by taking the following precautions:

  • staying indoors during and immediately after spraying;
  • closing all doors and windows;
  • avoiding trucks while spraying is underway;
  • turning off fans and air conditioners or setting them at exhaust;
  • removing clothes and children’s toys from outdoor areas;
  • covering swimming pool surfaces;
  • washing any household items or toys left outside before using them; and
  • ensuring homegrown fruits and vegetables are washed before eating.

More information about West Nile virus, including prevention, symptoms, weekly average trap counts of Culex tarsalis mosquitoes, fact sheets, posters and information for municipalities and health-care providers, is available at gov.mb.ca.

Manitobans can also contact Health Links–Info Santé at 204-788-8200 or at 1-888-315-9257 (toll-free) for more information.