Written collaboratively by Adam Varenhorst, Amanda Bachmann, Philip Rozeboom, Patrick Wagner, and Bradley McManus.
On June 15, 2026, the South Dakota Department of Health (SDoH) released a press release that the first West Nile Virus (WNV) positive pool of mosquitos was detected in Brown County. At this time, SDoH has not updated the Mosquito Surveillance Dashboard, but this is a good resource for monitoring WNV. Although much of the state is still experiencing drought (Figure 1), recent heavy rains will promote already active mosquito populations. It’s important to remember to always be vigilant and take precautionary measures to prevent mosquito bites.
If you are outside after dark, make sure to cover as much of your skin as possible by wearing long sleeves and pants. We also recommend using insect repellants that contain DEET or similar active ingredients to provide further protection. The U.S. Environmental Protection Agency provides a helpful tool for choosing a repellant that will provide the best protection based on the desired activities. Just like with sunscreen, repellents should be reapplied after a few hours per the label directions.
