News Releases

The chief medical officer of health advises that, as of end of day Wednesday, 142 additional positive human test results for West Nile virus have been reported in Manitoba since last week.  These new results predominantly reflect exposures to infected mosquitoes before mid-August.

 

To date, a total of 355 individuals have tested positive for West Nile virus (WNV) in Manitoba. Of these, 18 test results were identified by Canadian Blood Services routine screening and the donated blood units were discarded as planned. 

 

Ongoing mosquito surveillance indicates the numbers of active West Nile virus-infected mosquitoes are decreasing but continue to be present in most parts of southern Manitoba. Even though mosquito activity may appear to be low, the risk of exposure to West Nile virus this summer has not yet ended. The importance of taking personal protective precautions against mosquitoes continues.

 

As daytime and evening temperatures become cooler, Culex tarsalis mosquitoes may become more active in the afternoon and early evening. Manitobans are encouraged to reduce the risk of mosquito bites by:

·         reducing the amount of time spent outdoors in the afternoon and early evening when mosquitoes are now more active, and whenever mosquito activity is observed;

·         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.

 

No new orders under Manitoba’s Environment Act are being issued to control adult mosquitoes at this time. Adult mosquito control based on orders previously issued is not indicated at this time. 

 

The number of cases of the more severe type of West Nile virus (i.e. WNV neurological syndrome) in previous years has ranged from one to 35 cases per summer.  The total number of cases of West Nile virus in previous years has ranged from three to 143.  To date in 2007, 102 WNV human cases have been classified of which 21 are WNV neurological syndrome.

 

Additional information on human cases including age, gender, regional health authority of residence and likeliest area of exposure, as well as information on adult mosquito control schedules will be provided on the website as it becomes available at http://www.gov.mb.ca/health/wnv.

  

Information on weekly average trap counts of Culex tarsalis by regional health authority and a list of communities where infected mosquitoes have been found is available on the province’s West Nile virus website at http://www.gov.mb.ca/health/wnv.  Manitobans can check the West Nile virus website regularly for up-to-date data and information throughout the summer.

 

More information about West Nile virus is also available from Health Links–Info Santé at 788-8200 or 1‑888‑315-9257.

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