By Marcia Love
West Nile virus was confirmed in a mosquito pool in southwestern Saskatchewan earlier this week.
Cypress Health Region received notification from the Ministry of Health’s mosquito-monitoring program on Aug. 9 of the virus’ first appearance in the region this summer.
Dr. David Torr, consulting medical officer of health for Cypress Health Region, said the mosquito pool indicates the risk of the virus is now at a higher level.
However, mosquitoes tested in Maple Creek have not indicated the virus is present in the area.
The Culex Tarsalis mosquito, which is a known carrier of West Nile virus, is present in the town.
“The number of Culex Tarsalis mosquitoes is rising,” said Mark Caswell, town administrator.
Mosquito traps are set up in locations at the edge of town and within town to monitor the insect’s population and the threat of West Nile virus.
On Aug. 1 and 2, 748 mosquitoes were trapped outside of town. Of that number, 37 per cent were found to be the Culex Tarsalis mosquito.
Over the same two days, 129 mosquitoes were trapped within town.
“That number came up a bit less than usual,” said Caswell.
Of the mosquitoes trapped in town, 44 per cent were found to be Culex Tarsalis.
August is normally the month with the highest risk for West Nile virus to appear, as the presence of the Culex Tarsalis mosquito becomes more prominent.
“Almost half the mosquitoes now are actually the type that are known to carry West Nile,” Caswell explained.
But he also noted the mosquito population has dropped dramatically around Maple Creek within the past few weeks. Caswell is unsure of the reason for the reduced numbers.
“It could just be cool evenings, and there’s not as much standing water around as there used to be,” he said. “Even with the warmer weather, for whatever reason we’re not seeing the emergence of mosquitoes that I would have expected to see.”
The town is continuing its  larviciding, which it has been practicing all summer to control the mosquito population.
Caswell said the use of fogging is unlikely, as it is the least efficient way of controlling the insect’s presence.
Although no human cases of West Nile virus have been reported in the region yet, Cypress Health Region encourages people to take precautionary measures against being bitten by mosquitoes. This includes using DEET-based insect repellant and wearing long-sleeved clothing while outside, particularly around dusk and dawn when the Culex Tarsalis mosquito is most active.