Health experts say a confirmed case of West Nile Virus in Manitoba is connected to someone who travelled outside of the province, but that doesn’t mean there won’t be homegrown cases still to come this summer.
“We don’t think it was actually acquired in Manitoba at this point, but we can probably expect that we’re going to likely see some cases of human West Nile Virus this season,” Dr. Santina Lee told Global Winnipeg.
“We definitely do see fluctuations year to year, and there’s just so many different factors related to that. A lot (relates) to the weather — it has to be the right temperature, whether there’s been rain or not, wind … all of that factors in.”
Lee, an officer of health with the province, said while reported cases of the virus in humans are on the decline in Manitoba, those numbers are likely inaccurate, as many who are infected with the virus don’t show any symptoms.
“The vast majority of people who get infected with West Nile Virus are asymptomatic — have no symptoms at all, have no idea,” she said.
“This will vary on a scale of really mild, minor symptoms — fever, maybe some aches and pains — to having headaches, or more on the severe end, brain infection, brain inflammation and other neurologic symptoms.
“You never know if you are going to be in that percentage of people only mildly symptomatic or not symptomatic at all … or you might be the person who becomes really severely sick with this, ends up in the ICU, and may or may not make it out of the ICU.”
Lee said everyone who is infected has a different experience, and while she doesn’t want to raise alarm bells about the potential for infection, there are simple ways Manitobans can keep safe during the rest of the summer, including wearing insect repellant, avoiding outdoor time between dawn and dusk when the mosquitoes are more active and wearing long sleeves and long pants, especially if you’re going out at night.
You can also make sure there’s no standing water or other attractive situations for the mosquitoes to breed on your property.
“Avoiding and eliminating the types of environments the mosquitoes like to be in and breed … all of those can go a long way to reducing our risk for mosquito bites and specifically culex tarsalis.”
Entomologist Taz Stuart told Global Winnipeg an increase in the number of potentially West Nile-carrying insects has led to a second round of treatment in the Winkler area, following last week’s emergency fogging.
“If (a culex tarsalis mosquito) comes out of overwintering and she had West Nile from last year, she will then transmit it into the bird population, and they feed on birds initially in the start of the season,” he said.
“And then as we go into June and into July, they start moving into the larger animals and then humans. And this is where the August long weekend was key — that’s usually the highest transmission, and with Winkler and that area having such a high percentage of positive culex mosquitoes … the overall nuisance population is very, very low, so people don’t think there’s a problem, but tarsalis is a very sneaky biter.”