West Nile positive mosquitoes spread to Clarington, batches already found in Ajax, Oshawa, Pickering

Mosquitoes infected with West Nile Virus have been found in Durham Region’s traps in Clarington.

The Region’s Health Department traps and tests mosquitoes every week from June to September. So far they’ve detected 11 batches of positive mosquitoes; three in Ajax, three in Clarington, three in Oshawa and two in Pickering.

Mosquitoes spread the West Nile virus by drawing blood from an infected bird and then biting a human. People can’t get the virus from birds directly and can not spread it among themselves.

The virus first appeared in Canada in 2002 though infections are quite rare. In 2022 there were only 47 confirmed cases in the entire country, according to Statistics Canada. However, these are only confirmed cases. The true number of infections is likely higher.

Most who contract the disease will suffer mild symptoms such as fever, headache, body ache, nausea, vomiting, and rash on the chest, stomach or back. However, in rare cases, more serious symptoms present such as muscle weakness, stiff neck, confusion, tremors, numbness and sudden sensitivity to light.

Generally, symptoms show up between two days and two weeks after the infected person is bitten. Even when bitten, contracting the virus itself is quite rare but residents should take precautions just in case.

These include wearing shoes, socks and long-sleeved clothes while outdoors, using bug spray with DEET, removing standing water from their yards and ensuring screens are in good shape.

Although the risk of becoming infected is low, the Health Department recommends that residents take the following precautions:

• 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 window and door screens are in good repair to prevent mosquitoes from entering your home.