West Nile Virus Found in St. Charles County Mosquitoes

Mosquito biting

Several adult mosquitoes collected last week in traps set by the St. Charles County Division of Environmental Health and Protection have tested positive for the West Nile virus. This is the first positive test for the County this year, and officials say there is no reason for alarm.

 “County staff has been aware that West Nile virus is present in the metropolitan area, but this is the first time this season we have found the virus in St. Charles County mosquitoes,” says Ryan Tilley, Director of the Division of Environmental Health and Protection. “We are increasing treatment protocols for the surrounding areas and targeting known habitat areas to minimize the development of adult mosquitoes. This will assist us in controlling the spread of the virus.”

Tilley says residents can reduce the risk of contracting West Nile by using repellent containing DEET, picaridin, IR 3535, or oil of lemon eucalyptus when outdoors the rest of the summer and into fall. Additionally, they should remove or treat areas where water settles for several days, and keep gutters and yards free of debris where mosquitoes may collect.

This is the first year the County has used collection sites to analyze the size and types of mosquitoes. The traps were set up in various sites throughout the county in June, and will remain in place through September. The traps are checked and collections analyzed weekly.

“By using information from these collection sites,” Tilley says, “our staff can target specific areas where we need to decrease the overall mosquito population in the county.”

According to the Centers for Disease Control and Prevention (CDC), 42 states, including Missouri and Illinois, have reported West Nile virus activity this year. Approximately 80 percent of those who become infected with the virus do not experience any discomfort. Those who do can show symptoms such as fever, headache, body ache, fatigue, nausea or rash. In extreme cases, especially involving those 60 or older or who have previous medical conditions, the disease can cause brain inflammation, neck stiffness, seizures, coma and death. For additional information on the West Nile virus, visit www.sccmo.org/1038/West-Nile-Virus.

The purpose of the St. Charles County Mosquito Control program is to inspect problem areas and apply effective treatments to reduce the mosquito population; target habitat areas to control larvae; and spray to treat adult mosquitoes. In addition to efforts throughout unincorporated St. Charles County, the division contracts with several municipalities, including Augusta, Cottleville, Dardenne Prairie, Flint Hill, Lake Saint Louis, Portage des Sioux, St. Paul, Weldon Spring, Weldon Spring Heights and Wentzville. Residents who are concerned about nuisance mosquitoes should visit www.sccmo.org/mosquito, or call 636-949-1800, to request assistance. Those living within the city limits of O’Fallon, St. Charles and St. Peters should contact their respective city halls for information.