The South Dakota Department of Health announced on June 15 that the first West Nile virus detection of the 2026 season was found in a Brown County mosquito pool.
Dr. Joshua Clayton, State Epidemiologist for the Department of Health, said, “Protecting yourself against pesky mosquito bites is important for preventing West Nile infection. Using bug spray and limiting activities between dusk-to-dawn hours can reduce your risk of infection.”
The department recommends several precautions to prevent mosquito bites and reduce the risk of West Nile virus. These include applying mosquito repellents such as DEET, picaridin, oil of lemon eucalyptus, 2-undecanone, param-menthane-diol, or IR3535 to clothes and exposed skin; wearing pants and long sleeves in the evening; limiting time outdoors from dusk to midnight when mosquitoes are most active; removing standing water where mosquitoes breed by regularly changing water in birdbaths and pet dishes and draining flowerpots or garden containers; staying away from areas near standing water; and supporting local mosquito control efforts.
Personal precautions are especially important for people at high risk for severe illness from West Nile virus. This includes individuals over 60 years old, pregnant women, transplant patients, and those with cancer, diabetes, hypertension, or kidney disease. People experiencing symptoms such as severe or unusual headaches should consult their physicians.
Since 2002 when West Nile virus was first reported in South Dakota, there have been more than 2,952 human cases and 58 deaths statewide. Every county has reported cases over this period. The department noted that one human case had already been reported as an early season outlier this year.
For more information about West Nile virus or other health-related topics in South Dakota, residents are encouraged to visit the Department of Health website.
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