Ottawa Public Health (OPH) has confirmed the presence of West Nile virus in local mosquitoes, as well as the city’s first human case of 2024.
OPH has been monitoring mosquitoes for the virus since June 1.
In a press release Friday evening, the agency confirmed it had detected both the first positive cases in mosquitoes and the year’s first human infection.
The virus is currently posing a moderate to high risk to public safety, OPH public health inspector Alison Samuel said in an interview Saturday.
The person who was infected has now recovered, Samuel added.
In 2023, there were no confirmed cases of West Nile virus in Ottawa, although there were 54 confirmed cases across Ontario.
West Nile virus is primarily spread by the northern house mosquito, Culex pipiens. Only a small number of people bitten by a mosquito carrying the virus will become infected.
However, about 20 per cent of those infected may experience flu-like symptoms including fever, headache, muscle aches, and a rash.
Severe illness occurs in less than one per cent of infections, with the virus potentially affecting the central nervous system. The risk of severe illness increases with age and is also higher among people with weakened immune systems, according to OPH.
OPH is urging residents to take precautions against mosquito bites and prevent mosquito breeding by following these measures:
The City of Ottawa has also implemented a plan that includes weekly surveillance and mosquito larvicidal treatment of sites on city property where there’s standing water, OPH said.
