A sample of mosquitoes taken from Sunset Park in Festus tested positive for the West Nile virus, said Scott Darrough, the Jefferson County Health Department environmental vector technician.
Darrough said the test results were reported on Monday, and it was the first positive test in Jefferson County this year.
“It won’t be the last,” he said. “That virus builds as the season goes on. It builds in bird populations and mosquito populations.”
The mosquito season starts in mid-May and ends in mid-October, depending on weather.
Darrough said the city of Festus has its own vector program that sprays for mosquitoes, and according to the city’s website, Festus has increased spraying around the park, 816 Parkview Drive, and surrounding neighborhoods.
Darrough said the Health Department collects mosquito samples and conducts tests from locations in Festus, as well as throughout the county.
He said the Health Department has about 100 collection sites in the county, samples are collected and tested once a month.
Darrough said those who contract Nile virus have flu-like symptoms.