The Voice of the Community Since 1909, Serving Moorcroft and Pine Haven, Wyoming

Wyoming braces for mosquito season

Weed and Pest Council prepares for potential repeat of worst year of West Nile Virus cases since 2013 

After a notably bad year for mosquitoes, the Wyoming Weed and Pest Council (WWPC) is warning that the conditions so far in 2024 could mean we're set for another season of swatting.

While most mosquitoes limit their nuisance to itchy bites and buzzing, some carry a potentially serious disease: West Nile Virus.

In 2023, Wyoming saw the worst outbreak of the disease in a decade, with a case rate far exceeding the national average and four human deaths.

The year before, only three cases in total had been reported.

Bracing for a potential repeat of 2023, WWPC is working to learn as much as possible about the mosquito population in this state before hatching begins for the year.

West Nile Virus causes no symptoms in four out of five cases. However, about one in five people will develop a fever and symptoms including headache, joint pains, vomiting, diarrhea or rash.

Most people will recover completely, though the fatigue and weakness can last for weeks or months. About one in 150 people, though, will develop a serious illness affecting the central nervous system, such as encephalitis or meningitis, and about one of every ten of those people dies.

According to the Centers for Disease Control (CDC), Wyoming saw a total of 26 human cases of West Nile Virus last year. The Wyoming Department of Health reported in September that a significant number of them involved the more severe, neuroinvasive type of illness.

According to the WWPC, animals, particularly horses, are also at risk of exposure. Wyoming saw nearly 50 instances of equine-related cases last year, after just a single reported case the year prior. 

Crook County did not report any human cases of West Nile Virus in 2023, according to Wyoming Department of Health data. The county did experience one equine case.

According to WWPC, there is potential for a similar situation in 2024. The vast majority of West Nile Virus cases in humans occur in the summer, from July through September.