Ottawa has recorded its first human case of West Nile virus for 2026, prompting Ottawa Public Health to renew its call for residents to guard against mosquito bites as summer winds down into early fall.
According to CBC Ottawa, a city resident has tested positive for the virus, which is spread through the bite of an infected mosquito. Health officials say this is typically the point in the season when cases start to appear, since mosquito populations carrying the virus tend to peak in late summer.
What West Nile Virus Means for Ottawa Residents
Most people bitten by an infected mosquito will not develop symptoms at all. Ottawa Public Health notes that only about one in five people infected will experience mild symptoms, such as fever, headache, body aches, or a skin rash. A much smaller number of cases, less than one percent, can lead to serious neurological illness, including meningitis or encephalitis.
Older adults and people with weakened immune systems face a higher risk of severe illness if infected. Anyone in Ottawa who develops a sudden fever along with confusion, muscle weakness, or a stiff neck is being advised to seek medical attention promptly.
How the Virus Spreads Around the Capital
Mosquitoes pick up the virus by biting infected birds, then pass it on to people and animals through subsequent bites. Ottawa's river valleys, wetlands, and green spaces, from the Greenbelt to the pathways along the Rideau Canal, provide plenty of habitat for mosquitoes throughout the warmer months.
Ottawa Public Health has been monitoring mosquito activity across the city as part of its ongoing surveillance program, and this first confirmed human case for the year signals that residents should stay alert while the weather remains mild enough for mosquitoes to remain active.
Steps Ottawa Residents Can Take Now
Ottawa Public Health is recommending a few straightforward precautions for anyone spending time outdoors in the city:
Reduce Exposure
- Wear long sleeves and pants during dawn and dusk, when mosquitoes are most active
- Use a mosquito repellent containing DEET or icaridin
- Keep windows and doors screened to prevent mosquitoes from entering the home
Reduce Breeding Grounds
- Empty standing water from items like flowerpots, birdbaths, and eavestroughs around the house
- Report locations with significant standing water to the city
With Ottawa's mosquito season continuing into the fall, public health officials say ongoing vigilance remains the best defence against further cases in the city.
Source: CBC Ottawa
