WEST NILE CASES CONTINUE TO GROW

There are 26 new probable and confirmed cases of clinical illness due to West Nile Virus in Saskatchewan, reinforcing the need for Saskatchewan residents to take appropriate measures to avoid being bitten by mosquitoes.

"We are experiencing a West Nile Virus outbreak in this province, and so it is very important that everyone take precautions for the remainder of the mosquito season during this summer and fall," said Dr. Eric Young, Saskatchewan's Deputy Chief Medical Health Officer.

With the long weekend approaching, Saskatchewan Health, with assistance from Saskatchewan Environment, is issuing a warning to campers about protecting themselves. A one page alert is being distributed to everyone entering provincial parks. It informs people of the West Nile Virus outbreak in Saskatchewan, and asks them to take appropriate precautions to avoid mosquitoes. This same message is important for people out working in their gardens and for farmers out in the fields.

The area experiencing the highest rate of infection is the Five Hills Health Region. Of the 69 probable and confirmed cases in Saskatchewan, over 30 per cent of them are occurring within that region. The cases are spread throughout Five Hills, but primarily in rural areas in the southern half of the region.

"We are monitoring the situation," said Dr. Mark Vooght, Medical Health Officer for the Five Hills Regional Health Authority. "We do not want to speculate as to the relatively high numbers of infection in our region, but possible contributing factors may include the abundance of suitable mosquito habitat, such as creeks, coulees and patches of dense vegetation. Warm weather was also a factor."

Even with the good growing conditions, mosquito numbers in Five Hills and throughout the rest of Saskatchewan are below the ten-year average. The following are current findings from 150 mosquito traps in 50 locations in the province:

• 16 of the 459 mosquito pools captured to date traps contain West Nile Virus positive mosquitoes;
• Positive pools were found in Assiniboia, Gull Lake, Melville, Dundurn, Saskatoon, Lloydminster, Humboldt, Kindersley and Regina;
• Thirteen of the 16 positive pools are Culex tarsalis; the other three are Culex restuans, another species that can also carry West Nile.
• Between 0.5 per cent and one per cent of Culex tarsalis mosquitoes are West Nile Virus positive, considered a very high rate of infection.

Larvaciding is continuing throughout Saskatchewan, as the mosquito surveillance data shows new mosquitoes are still being hatched.

"Adulticiding remains ineffective because of the overall low numbers," said Young. "However, if at any point it is deemed necessary by medical health officials, adulticiding could take place with 48 hours notice."

Other new cases are in the Cypress, Heartland, Regina Qu'Appelle, Sun Country, Saskatoon, and Sunrise health regions. The majority still tend to be mild or moderate West Nile fever.

The attached chart illustrates the latest number of cases in the province.

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For More Information, Contact:

Mark Rathwell Health Regina Phone: (306)787-4083