Outbreak of Cyclosporiasis Among Patrons of a Mexican-Style Restaurant - Limestone County, Alabama, May-June 2023

In early June 2023, the Alabama Department of Public Health identified five laboratory-confirmed cyclosporiasis case reports with a common patient exposure of eating at one Mexican-style restaurant. Common signs of cyclosporiasis include diarrhea, abdominal cramps, nausea, and loss of appetite. Although most illnesses are self-limited, antibiotic treatment can prevent relapsing illness. Onset of illness for the initial five patients occurred during May 26-30. An outbreak investigation was initiated on June 7. Routine case investigations and case finding through the restaurant's food delivery service contact list identified 42 additional cases. Multivariable analysis of case-control study data revealed that illness was associated with consumption of cilantro (odds ratio = 40.9; 95% CI = 6.4-808.6). The cilantro was traced back to a Texas firm with no identified food manufacturing license that sourced the product from Mexico. The outbreak and its investigation demonstrate the ongoing need for regulatory controls of produce suppliers, documentation and review of business licenses, and increasing public awareness of food safety and outbreaks. Distribution of potentially contaminated products via improper supply chain channels remains a public health challenge. Avoiding infection in the United States involves preventing contaminated produce from reaching local retailers and consumers.