Public health officials say the risk for human exposure to West Nile Virus is high right now in the Southern Health-Sante Sud region.
As a result, two ministerial orders have recently been issued, under the Environment Act, to fog for mosquitoes in the Winkler and Altona areas.
Public health officials say wet conditions early in the season and recent hotter, drier weather have created ideal conditions for Culex Tarsalis mosquitoes, which are the ones capable of carrying West Nile Virus.
Dr. Mahmoud Khodaveisi, Medical Officer of Health with Southern Health-Sante Sud, explains that a mosquito becomes infected after sucking the blood of a bird that is carrying the virus. Within the next two weeks, the mosquito is then capable of transmitting the infection to humans. Mid-July to mid-August is historically the highest risk period for contracting West Nile Virus in southern Manitoba.
According to Dr. Khodaveisi, if a mosquito infected with West Nile Virus bites a human being, 80 per cent of the time they experience no symptoms. He notes of the remaining 20 per cent, most will experience mild flu-like symptoms, including fever, headache, and muscle ache. They might also notice skin rash and stomach or back pain.
"But unfortunately, one per cent of those infected with West Nile Virus, they experience serious illness involving their central nervous system," he says. "In this situation, the person would have more serious symptoms like high fever, headache, stiff neck, confusion."
At this time, no locally acquired human cases of West Nile Virus 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-coloured, loose-fitting clothing with long sleeves and pant legs,
- maintaining door and window screens, and
- cleaning and emptying yard items that collect water.