Health Department reports season’s first positive mosquitoes for West Nile Virus

Whitby, Ontario - Durham Region Health Department has received notification of adult mosquitoes that have tested positive for West Nile virus (WNV). Batches of positive mosquitoes have been reported from two trap sites – one located in Oshawa, the other located in Clarington. Positive confirmation was received on July 21. These are the first mosquitoes in Durham Region to test positive for WNV this season.

Positive test results indicate that WNV is present in the mosquito population. The Health Department cautions that with positive test results, it’s important for area residents to take precautions against WNV by avoiding mosquito bites and removing standing water from their properties.

West Nile virus is a mosquito-borne disease that is spread to humans via the bite of an infected mosquito. Mosquitoes become infected by feeding on the blood of a bird that carries the virus. The disease is not passed from person to person or from bird to person. Most people who contract the virus will experience mild illness including fever, headache, body ache, nausea, vomiting, and rash on the chest, stomach or back. More serious symptoms can include muscle weakness, stiff neck, confusion, tremors, numbness, and sudden sensitivity to light. Symptoms usually develop between two and 15 days after being bitten by an infected mosquito.

Although the risk of becoming infected is low, residents should still take the following precautions to minimize the risk of mosquito bites and the possibility of being infected with WNV:

• Wear shoes, socks, and light-coloured clothing, including long sleeve tops and full-length pants when outside, especially at dusk or dawn when mosquitoes are most active.
• Use insect repellent containing DEET or Picaridin on exposed skin, following Health Canada’s safety tips on using personal insect repellents.
• Remove standing water from your property where mosquitoes can breed.
• Ensure that window and door screens are in good repair to prevent mosquitoes from entering your home.

Durham Region Health Department sets mosquito traps across the Region and submits mosquitoes for laboratory testing every week between June and September. In addition, regional catch basins and other stagnant water sites are treated with a larvicide to reduce mosquito breeding. For more information on WNV, please call Durham Health Connection Line at 905-668-2020 or 1-800-841-2729 or visit durham.ca/westnile.

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For more information, please contact the Health Department.