Epidemiological investigation reports widespread cyclosporiasis infections in Michigan residents, indicating contaminated iceberg lettuce and restaurant exposures as likely sources.
Key Points
Investigate and characterize an unprecedented seasonal outbreak of cyclosporiasis across Michigan to identify likely exposure sources.
Conducted state-level surveillance and case identification across 69 Michigan counties for illnesses with onset between May 10 and July 18, 2026 (N = 6,065).
Administered standardized food exposure questionnaires to infected individuals, obtaining dietary history for 51.3% of identified cases.
Identified 6,065 confirmed cyclosporiasis cases across 69 of Michigan's 83 counties as of July 22, 2026, substantially exceeding historical seasonal baselines.
Food history interviews from 51.3% of cases identified consumption of iceberg lettuce and meals from a single restaurant chain as potential exposure vehicles.