GRAND RAPIDS, Mich. (Michigan News Source) – Three people have been hospitalized in Ottawa and Kent counties with West Nile virus.

Health officials said none of the three had recently traveled and doctors believe they were bitten by an infected mosquito in west Michigan.

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This is the highest number of West Nile Virus cases in Ottawa County since 2018. Cases happen during mosquito season, which begins in the summer and continues throughout fall.

West Nile Virus can cause serious illness, and there are no vaccines to prevent it or medications to treat it. Most people who become infected do not feel sick, and about 1 out of 150 people individuals develop a serious illness, according to health officials.

For more information on West Nile Virus symptoms click here.