Toronto Public Health and York Region Public Health have confirmed the first detection of West Nile virus in local mosquitoes this summer.
York Region officials say a mosquito trap located near Weston Road and Rutherford Road tested positive for the virus, marking the first confirmed case in the region’s mosquito population for 2025.
TPH reported that three mosquito batches tested positive during its annual surveillance from June to September. The public health unit says 22 mosquito traps are set up throughout the city each week.
“These mosquitoes are grouped into batches, also known as pools and tested for the virus,” Toronto Public Health noted.
Health officials say they will continue to monitor for further signs of West Nile activity and urge residents to remain vigilant throughout the summer.
West Nile virus is a mosquito-borne illness that can be transmitted to humans through the bite of an infected mosquito. While most people experience mild or no symptoms, the virus can cause serious illness in some cases, particularly in older adults or those with weakened immune systems.
Symptoms typically develop between two and 14 days after a bite from an infected mosquito and may include fever, headache, nausea, vomiting, body aches, skin rash and swollen lymph nodes.