WASHINGTON — U.S. health authorities are investigating a surge in cyclosporiasis cases and a potential link to contaminated iceberg lettuce, as federal officials work with states to trace illnesses caused by the Cyclospora parasite.
The U.S. Food and Drug Administration said its investigation had identified a common supplier of shredded iceberg lettuce served at Taco Bell locations where people who later became ill had eaten. Taylor Farms de Mexico on July 17 voluntarily removed iceberg lettuce sourced from central Mexico from the U.S. market and initiated a recall covering certain retail and food-service products.
The FDA said the investigation remained ongoing and that, as of July 19, no product samples had tested positive for Cyclospora. The agency cautioned that epidemiological and traceback evidence can point to a potential source even when laboratory testing of food does not confirm contamination.
The FDA reported 1,644 illnesses and 94 hospitalizations in a five-state outbreak involving Indiana, Kentucky, Michigan, Ohio and West Virginia, with no deaths reported. The agency said the last illness onset recorded in that investigation was July 13. It also noted that state figures may differ because states can include probable cases and reports that have not yet been confirmed or transmitted to federal authorities.
The recalled lettuce was distributed to food-service customers and retailers, including Walmart, with distribution confirmed in 27 states, according to the FDA. The agency advised consumers, restaurants and retailers to discard recalled products and urged people with symptoms of cyclosporiasis to contact a healthcare provider, particularly if they had eaten shredded iceberg lettuce before becoming ill.
Cyclospora cayetanensis is a parasite that can cause prolonged diarrhea and other intestinal symptoms. The FDA said the parasite is associated with contaminated food or water and has previously been linked to fresh produce, including leafy greens and herbs. The agency has also documented outbreaks in which investigators could not identify a specific food source despite epidemiological investigations and product testing.
The investigation comes as U.S. health officials continue monitoring a broader increase in cyclosporiasis cases during the 2026 season. Federal and state agencies are collecting and analyzing additional samples and traceback information to determine whether the recalled lettuce is responsible for the illnesses and whether further products or distribution areas should be included in public health advisories.
