News Releases

The chief medical officer of health advises that, as of noon today, 107 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 213 individuals have tested positive for West Nile virus in Manitoba.  Of these, 18 test results were identified by Canadian Blood Services routine screening and the donated blood units were discarded as planned. 

 

Two West Nile virus-related deaths were reported earlier this month. West Nile virus was likely the cause of one of the deaths. The role that West Nile virus played in the second death is under investigation.

 

Ongoing mosquito surveillance indicates that West Nile virus-infected mosquitoes continue to be present in all parts of southern Manitoba.  To date, no evidence of West Nile virus-infected mosquitoes has been found in the NOR-MAN, Burntwood and Churchill health regions.  The province continues to monitor adult Culex tarsalis mosquito numbers throughout Manitoba.  

 

Even though mosquito activity may appear to be low, the risk of exposure to West Nile virus this summer has not yet ended. For the remainder of August and early September, the importance of taking personal protective precautions against mosquitoes continues.

 

As daytime and evening temperatures become cooler, Culex tarsalis mosquitoes may become more active earlier in the day as well as between dusk and dawn. Manitobans are encouraged to reduce the risk of mosquito bites by:

·        reducing the amount of time spent outdoors during peak mosquito hours between dusk and dawn or whenever mosquitoes are active;

·        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 (neurologic illness) 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.  It is too early to know or to predict the number of severe cases that will be reported this year.

 

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 province’s West Nile Virus website at http://www.gov.mb.ca/health/wnv as it becomes available.

 

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 also available on the website. Manitobans can check the site 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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