North Dakota has reported 79 human cases of West Nile virus in 2025 – the most since 2018, when 204 cases were reported.

More than half of those cases have been detected in people 50 or older, according to the state health department's dashboard . There have been cases reported in 23 North Dakota counties, including 16 in Cass County and 14 in Burleigh County.

When case numbers surged in August, state health officials warned North Dakota residents to take precautions to avoid mosquito bites. Nationally, 42 states had reported a total of 1,137 human cases of West Nile virus as of Sept. 23, according to the Centers for Disease Control and Prevention .

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What is West Nile

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