GILLETTE, Wyo. — Following the worst year for West Nile Virus in Wyoming since 2013, the Wyoming Weed and Pest Council is extending a series of tips to all Wyoming residents on how to reduce their chances of contracting this rare disease in preparation for what could be another active year.
According to the Wyoming Department of Health, only three cases of West Nile Virus were reported in humans in 2022. The following year, that number would increase to 27, which puts Wyoming’s 4.8 cases per 100,000 people far above the national average of 0.7 in 2023, a Wyoming Weed and Pest Council release stated. The four fatalities from the virus in 2023 were the first the state has seen since 2018.
The Wyoming Weed and Pest Council said in the release that spring is the catalyst to an increase in mosquito populations. Warmer weather and the greater accessibility to standing water produced by snowmelt characteristic of spring create ideal conditions for the insects to reproduce.
Although many mosquito species only produce relatively benign and itchy bites, others can harbor West Nile Virus, a potentially fatal illness.
The Wyoming Weed and Pest Council also recognizes that horses are at considerable risk of contracting the virus, with 50 equine cases in 2023. Only a single case was recorded in horses in 2022.
These numbers also only constitute what’s been reported. According to Sheridan County Weed and Pest Assistant Supervisor Brian Songer in an interview with Oil City News, the highest number of reported cases from last year came from areas with the capabilities to test for the virus. There are certainly areas within the state remote enough to prevent accurate and comprehensive testing that likely make the actual number of cases higher than what was reported, Songer said.
Weed and Pest’s efforts to control and monitor mosquito populations
The Wyoming Weed and Pest Council and the Sheridan County Weed and Pest District have partnered with the city of Sheridan to conduct and plan efforts to control the mosquito population before it reaches its highest level. According to Songer, the larvae harvested are coming in significant quantities.
“We bring them back to our office and watch their development daily and try to determine when the adults will start hatching,” Songer said in the release.
Through collection, Weed and Pest tries to predict which type of adult mosquito will affect the area.
“By doing this, we can predict when we’ll start seeing adults and whether they are a simple nuisance or carry West Nile Virus.”
Songer said that there are two schools of thought regarding why concerns over West Nile Virus in mosquitos trend into following years.
“Because we had West Nile Virus last year, it’s likely to transfer to this year because the mosquitos that carry the virus, Culex [tarsalis], overwinter as adults. They could carry the virus from one year to the next,” Songer said.
Songer added that the second possibility regarding why West Nile Virus could continue to be a concern throughout the state is that birds who consume the mosquitos can later transmit the disease to humans and horses. However, he noted that if this were the case, the birds less resilient to the disease would have died last year, leaving only the more resistant individuals. That would mean there would be slightly less concern of transmission to humans.
“We are very concerned that the trend will continue and that’s why we’ve ramped up our program, trying to get out and predict where the mosquitos are and make our larval treatments more effective,” Songer said in the release.
What can Wyoming residents do to protect themselves and prevent contraction?
Because there is still considerable concern over West Nile Virus in the state, the Wyoming Weed and Pest Council suggests residents take some steps to limit the mosquito population in their area.
Minimize standing water sources
The Weed and Pest Council states that things ranging from buckets and old tires up to full ponds could be potential breeding grounds. Anywhere standing water can collect is a concern. This includes excess water resulting from over-irrigated soils in pastures as well as culverts with blockages.
Prevent bites
Mosquito-proof or long-sleeved clothing goes a long way in keeping mosquitos from biting. The Weed and Pest Council also encourages Wyomingites to treat boots, pants and socks with approved insect repellent.
Protect arms and legs of small children
Make sure to apply repellent to babies and children. The council suggests using one’s hands to apply the repellent to avoid sensitive areas like the eyes, the mouth and cuts. Apply repellent after sunscreen, not before.
Vaccinate horses for West Nile Virus
The Wyoming Weed and Pest Council suggests this be done in the spring. The council also encourages fans and sprays for horses and suggests they be put away during dawn and dusk.
Know the symptoms of West Nile Virus
Most carriers of West Nile Virus may not exhibit symptoms. Those who do experience symptoms could have headaches, fevers, nausea, joint pain, diarrhea and rashes, according to the Centers for Disease Control. The Wyoming Weed and Pest Council encourages residents experiencing symptoms to seek their doctor and to report to the council if any human or animal on their property is diagnosed.
Communicating and organizing locally can limit contraction and increase awareness
Alongside efforts to monitor the risk West Nile Virus has on Wyoming this year, Songer said that Sheridan County Weed and Pest is in communication with other local organizations to stay up to date on what Sheridan, Ranchester and Dayton are dealing with. He added that he’s seen similar communication efforts in other counties.
“Everybody’s communicating. Everybody’s aware that there’s potential out there and they’re looking for the symptoms,” Songer said. “That same idea is pretty prevalent across the state, I think. Teton County, Cheyenne, Laramie — all those places have similar programs in place.”
That information then gets funneled to the Wyoming Department of Health, where it is dispersed to emergency management coordinators and used to benefit and aid communities all across the state, Songer said.
For more information on the potential symptoms of West Nile Virus, see the corresponding CDC web page. To report cases or concerns of West Nile Virus, contact the Wyoming Weed and Pest Council via the council’s contact page.
