News Releases

Media Bulletin - Manitoba

July 29, 2016

West Nile Virus Update #1



Manitoba Health, Seniors and Active Living reports that its mosquito surveillance program has identified this season’s first Culex tarsalis mosquito samples infected with West Nile virus (WNV).  At this time, no human cases of West Nile virus have been identified in Manitoba. 

The infected mosquitoes were collected during the week of July 20 from adult mosquito traps in Altona, West St. Paul and Winkler. While most mosquitoes collected to date have been nuisance species which do not transmit WNV, the numbers of Culex tarsalis mosquitoes collected continue to increase.  There are currently no orders for adult mosquito control in Altona, West St. Paul, Winkler or elsewhere in the province. 

The potential for human exposure to infected Culex tarsalis mosquitoes is present throughout southern Manitoba. The risk of exposure to WNV is expected to continue in the coming weeks, particularly if warm and dry conditions persist, as these are ideal for Culex tarsalis development and activity. 

Manitobans can reduce the risk of mosquito bites and exposure to West Nile virus by:

  • reducing the amount of time spent outdoors during peak mosquito hours between dusk and dawn;
  • using appropriate mosquito repellent;
  • wearing light-coloured, loose-fitting clothing; and
  • maintaining door and window screens so they fit tightly and are free of holes. 

Manitobans can reduce the number of mosquitoes around their homes by eliminating standing water.  To prevent the development of Culex tarsalis mosquitoes, homeowners can:

  • clean eavestroughs and regularly empty bird baths, old tires and other items that collect water;
  • ensure rain barrels are covered with mosquito screening or are tightly sealed around the downspout; and
  • improve landscaping to prevent standing water around the home. 

The province offers a cost-shared larviciding program for municipalities and communities to take steps to help control Culex tarsalis mosquitoes.  To date this year, 53 communities are participating in the program.

Information on the risk of West Nile virus will continue to be provided to the public throughout the summer.  Manitobans can also check the WNV website regularly for up-to-date data and information. 

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

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

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