Arnold Mosquitoes Test Positive for West Nile Virus at 2 Trap Sites

Q: West Nile virus is in Jefferson County, but who is actually responsible for eliminating the mosquito threat?

In Jefferson County, the Health Department is not the agency that eliminates mosquitoes; it only tracks the virus and alerts the public. In Arnold, actual control responsibility falls to the city or whatever local mosquito-control contractor or program the city uses, because the department said it has “no control jurisdiction” there and has notified city officials of the positive traps. That means the Jefferson County Health Department’s role is surveillance: trapping mosquitoes, testing them for West Nile virus, and warning residents and local governments when the virus is detected. The agency will keep monitoring countywide, but it cannot order or carry out control measures in Arnold. In practice, mosquito reduction is usually handled by municipal governments, mosquito abatement programs, or contracted vector-control companies. The material provided does not identify Arnold’s specific operator, so the clearest answer is that Arnold city officials are the public authority expected to decide on any spraying, larvicide work, or other response. Residents also share responsibility, because much of mosquito control happens on private property. Health officials are urging people to remove standing water weekly, scrub containers, maintain screens, and use EPA-approved repellents and protective clothing. That matters because mosquitoes often breed in small household water sources, and West Nile prevention depends heavily on community action as well as government response.

3 articles · Updated · Leader Publications · Jul 17

Two Arnold mosquito trap sites yielded adult mosquitoes that tested positive for West Nile virus on July 15, prompting the Jefferson County Health Department to alert city officials.
The county health department said it conducts surveillance in Arnold but lacks control jurisdiction there, while its mosquito program continues monitoring for West Nile across Jefferson County.
Residents were urged to use EPA-approved repellents containing DEET, picaridin, oil of lemon eucalyptus, IR3535 or 2-undecanone and to wear clothing that covers exposed skin.
The department also advised removing standing water at least once a week and scrubbing containers to cut mosquito breeding and reduce the risk of mosquito-borne disease.