Michigan links severe diarrhea outbreak to contaminated salad greens as cases exceed 2,600

Michigan is experiencing a severe cyclosporiasis outbreak, with 2,640 cases reported as of July 13, a 69% weekend surge that far exceeds the typical 40-50 annual cases. The state's Department of Health and Human Services has linked the outbreak to potentially contaminated salad greens. The illness is caused by the microscopic Cyclospora parasite, leading to severe gastrointestinal symptoms like explosive diarrhea.

Michigan cyclosporiasis outbreak

• ▪Michigan reported 2,640 cases of cyclosporiasis as of July 13, 2026.
• ▪Michigan normally sees only 40 to 50 cases of cyclosporiasis per year.
• ▪The number of cases in Michigan represents a 69% surge over the weekend of July 11-12, 2026.
• ▪The national surge in cyclosporiasis cases is largely driven by spikes in Michigan, Ohio, and New York.
• ▪Nationally, the current cyclosporiasis surge includes more than 2,000 reported cases and 80 hospitalizations in over 30 states.

Contaminated salad greens source

• ▪Michigan's Department of Health and Human Services identified contaminated lettuce or salad greens as a potential source of the outbreak.
• ▪The state's health department noted that other sources for the cyclosporiasis outbreak cannot be ruled out.

Cyclospora parasite symptoms

• ▪After being consumed, the Cyclospora parasite takes hold in the intestines.
• ▪Symptoms of the illness can include nausea, stomach cramps, and potentially explosive diarrhea lasting for weeks.
• ▪Cyclosporiasis is a gastrointestinal illness caused by consuming the microscopic Cyclospora parasite.

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