Skip to content

Province warns of West Nile risks

The Government of Saskatchewan is reminding people to protect themselves from mosquito bites. In the last week, the Government of Saskatchewan has found the type of mosquito that carries the West Nile virus – the culex tarsalis – in 6.
West Nile Virus
Government of Saskatchewan graphic

The Government of Saskatchewan is reminding people to protect themselves from mosquito bites.

In the last week, the Government of Saskatchewan has found the type of mosquito that carries the West Nile virus – the culex tarsalis – in 6.6 per cent in an area that includes Humboldt, Regina and Saskatoon.

“The culex tarsalis reaches higher numbers and starts earlier in the south… it’s a common open grassland mosquito or field mosquito. It’s rarely found in the forest… It’s just not good habitat,” said Philip Curry, the province’s West Nile virus co-ordinator.

“There’s fewer of them the further north you go. So Saskatoon, Humboldt would be about a week behind and then as you get up to Prince Albert and Melfort there’s still culex tarsalis up there but there’s not as many of them and they don’t have as long of a season.”

Each part of the province is broken down into one of four zones, based on ecological risk areas, with northern Saskatchewan sitting in Zone 1, north central Saskatchewan in Zone 2, south central and south eastern Saskatchewan in Zone 3 and south western Saskatchewan in Zone 4.

While positive mosquitos continue to grow in southern and south central Saskatchewan and conditions remain favourable for transmission, the number of positive cases found in humans so far this summer sits at just one, with no neuroinvasive positive tests or deaths reported.

Eighty per cent of people experience little or no symptoms associated with West Nile, but 1-in-5 will develop severe symptoms including headache, fever, neck stiffness, disorientation, tremors, muscle weakness, and potentially paralysis, among others.

Approximately 1-in-150 can contract the neuroinvasive strain of West Nile, which can bring hospitalization, intravenous fluids, and respiratory support, among others.

The first symptoms typically appear two to 15 days after infection, and while in general recovery time is within a week, some of the more severe cases can have lasting health effects months or even years later, while other even more severe cases can result in death.

Culex tarsalis are most active on warm evenings between dusk and dawn, and while mosquito numbers are actually decreasing, the culex tarsalis is a slower growing breed, starting out with small numbers in the fall and getting larger as the months tick by.

“This tarsalis is out there right now… even though you don’t think there’s a lot of mosquitoes out there. The ones that carry West Nile are definitely out there and we’re starting to see an increasing number of them that are infected,” said Curry.