Mosquito trap counts have increased more than 50 per cent compared to the same time last year, according to the consulting firm contracted by the city to monitor and control mosquito populations.
A long, cool, wet spring allowed early mosquito varieties to thrive and they've stuck around, according to GDG Environment project manager Mark Ardis.
"Compared to years past, especially the past three years, mosquito populations are much higher than what we've observed in the past," Ardis said.
"We've got spring mosquitoes and we've got these early summer mosquitoes, and now we're going to see what we call cat-tail marsh mosquitoes emerging as well. So we're going to see I guess a triple whammy of mosquitoes emerging within the next few days."
There are about 20 mosquito species that breed in Ottawa, only one of which carries West Nile virus.
So far, with the West Nile-carrying mosquitoes only starting to emerge, the virus hasn't yet been detected in the region.
It's recommended people wear light clothing with long sleeves, especially at dusk and dawn. They should also use personal protection such as deet, check window screens and clean up any standing water sites on their properties.