New York has recorded the highest number of cyclosporiasis cases in the U.S. between May 1 and June 16, 2026, according to the Centers for Disease Control and Prevention (CDC). Illinois and Texas follow New York in total case counts.
The parasitic infection typically peaks in the U.S. between May and August. This year, the CDC recorded at least 145 cases across 17 states during that six-week window, though the agency notes the actual number of sick individuals is likely higher than the reported count.
The Michigan Surge
While the national trend is steady, Michigan is facing a “sudden and large” increase in infections. Since June 22, 2026, more than 170 cases have emerged across seven counties: Monroe, Lenawee, Washtenaw, Wayne, Livingston, Shiawassee and Jackson.
The numbers are an anomaly. A spokesperson for the Michigan Department of Health and Human Services (MDHHS) told TODAY.com that the state typically identifies only 50 cases per year.
Contaminated Produce and Symptoms
The parasite spreads through contaminated food, with fresh produce often cited as the common link. Once contracted, the infection causes “explosive” watery diarrhea.
The impact has been wide-reaching. Those infected range in age from 5 to 86 years old. To date, there have been at least 20 hospitalizations nationwide, though no deaths have been reported.
Tracking the Outbreak Source
The CDC is working with local officials and the U.S. Food and Drug Administration to investigate the clusters. On July 1, the agency stated there is “no evidence of a single, multi-state cyclospora outbreak linking all cases
Crucially, those infected reported eating food within the U.S. and had not traveled internationally in the weeks before becoming ill.
A Rising National Pattern
The U.S. generally sees several hundred cases of cyclosporiasis annually, but the CDC reports that infections have increased significantly in recent years.
The volatility was evident in a 2023 CDC report, which identified an unusually high 4,703 infections in 2019.
Consult your healthcare provider if you experience symptoms of gastrointestinal illness.
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