JACKSON, Wyo. — Teton County Weed and Pest District (TCWP) has detected the West Nile virus in mosquitoes. This marks the first detection of 2022.
TCWP detected the virus Friday in samples taken from mosquitoes trapped throughout the valley. In the lab, they separate the mosquitoes by species and then place them in pools of 50 or fewer. Out of ten mosquito pools tested, one has returned positive for the virus.
According to TCWP, West Nile Virus is an arbovirus (ARthropod BOrne VIRUS) that naturally cycles within local bird populations. It is passed along most often through the bite of a female mosquito, which comes looking for blood from the bird for protein to create a batch of eggs.
If there are enough virus particles in the blood of the bird to withstand the mosquito’s digestion process and to spread to her salivary glands, the mosquito then becomes able to pass along the virus to the next bird, horse, or human that she bites.
The Wyoming Department of Health (WDH) explains that while there are no vaccines or medications to treat the virus, most individuals infected experience no symptoms.
“About 1 in 5 people who are infected will develop a fever with other symptoms,” said the WDH. “Less than 1% of infected people develop serious, sometimes fatal, neurologic illness.”
The WDH reminds the public that while mosquitoes are most active at dusk or dawn, some bite during the day. Mosquitoes will bite if you enter an area where they are resting, such as high grass or heavy underbrush. While it is not necessary to limit outdoor activity (unless there is evidence of mosquito-borne disease in the area), individuals can and should reduce their risk of being bitten by mosquitoes.
Historically in Teton County, the host’s preference of the main vector has been shown to shift as the season progresses. In May and June, they mostly infect birds. Come July, August and September, they shift to more of a mammal-based diet.
“For this reason, it is important to stay vigilant and protect oneself against mosquito bites long into the season, even when the peak number of summer mosquitoes has dissipated,” says TCWP.
As West Nile Virus activity starts to appear in the area, TCWP encourages the public to adhere to the “5 D’s.”
Teton County residents can help TCWP learn more about what adult mosquitoes are doing in Teton County this summer by completing this survey.
