The Centers for Disease Control and Prevention (CDC) have identified a connection between cases of a parasitic disease and lettuce in 15 U.S. states. In 2023, cyclospora cases have been reported in at least 47 states, with ongoing investigations to determine the extent of contamination from a common source.

Initially, the outbreak was associated with lettuce served at Taco Bell, but federal authorities now focus on Taylor Farms. The company has withdrawn iceberg lettuce grown in central Mexico from the market.

Dr. Juan Luis Marquez, medical director at Washtenaw and Livingston health departments in Michigan, highlights challenges in investigating cyclospora outbreaks due to the latency period between exposure and symptom onset. Interviewing affected individuals to pinpoint common exposures involves extensive effort amid personnel cuts at public health levels.

According to the CDC, cyclospora, a microscopic parasite, often causes frequent and sometimes severe diarrhea. Outbreaks typically peak in late spring and summer, with the parasite spreading via fecal contamination. The disease, ciclosporiasis, is less common than foodborne illnesses from pathogens like salmonella and E. coli, with many cases lacking linkage to a specific food or source.

The U.S. hardest hit by cyclospora was in 2019, recording around 4,700 infections nationwide. Currently, Michigan alone reports over 12,000 cases, including two deaths. Combined with other states, the national count exceeds 25,000.

The Food and Drug Administration (FDA) is currently monitoring five separate cyclospora outbreaks. The outbreak in 15 states is the largest, with no specific product tied to the other outbreaks, including one affecting 115 individuals.

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