West Nile Virus Confirmed in Whitby Mosquitoes; Clarington Among Affected Areas

Adult mosquitoes collected in Whitby have tested positive for West Nile virus, according to the Durham Region Health Department. This represents the first positive batch identified in Whitby this season. In total, 19 mosquito batches across Durham Region have tested positive for the virus this year—four in Clarington, seven in Oshawa, three in Ajax, four in Pickering, and one in Whitby.

West Nile virus is transmitted to humans through the bite of an infected mosquito. The Durham Region Health Department reports that mosquitoes contract the virus by feeding on the blood of birds carrying West Nile virus. The virus is not spread from person to person or directly from birds to humans.

According to the Health Department, most people infected with West Nile virus experience mild symptoms such as fever, headache, body ache, nausea, vomiting, or rash on the chest, stomach, or back. Severe symptoms, which are less common, may 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.

The Durham Region Health Department conducts mosquito surveillance by setting traps across the region and submitting mosquitoes for laboratory testing every week between June and September. The region also treats catch basins and other stagnant water sites with larvicide to help reduce mosquito populations.