Federal health officials have officially declared the largest cyclospora outbreak in United States history to be over.
The Centers for Disease Control and Prevention announced on Friday, September 11, that the multi-state outbreak has run its course, with recalled produce no longer on retail shelves or in commercial kitchens. By the time the outbreak subsided, the microscopic parasite had sickened 12,883 people across 21 states, hospitalizing at least 570 individuals and killing two, according to joint data released by the CDC and the Food and Drug Administration.
Michigan bore the brunt of the infections, with rates climbing so high that approximately one in every 1,000 residents contracted the illness. The scale of the outbreak eclipsed all prior domestic records for cyclosporiasis, a disease caused by the single-celled intestinal parasite Cyclospora cayetanensis.
Investigators traced the infection cluster to patrons who had eaten shredded iceberg lettuce at Taco Bell restaurants. Federal contact tracers followed the tainted supply back to Taylor Farms de Mexico, which sourced iceberg lettuce grown in central Mexico.
On July 17, Taylor Farms issued a widespread voluntary recall covering bulk produce sent to institutional food service operators alongside bagged grocery items, including Marketside-brand shredded lettuce and salad kits sold at Walmart locations. Health regulators noted that the vast majority of patients contracted the infection before the mid-July recall went into effect.
Because cyclosporiasis can take up to two weeks to produce symptoms and several additional weeks for lab confirmation and epidemiological reporting, official case numbers continued to rise well after the contaminated produce had been removed from circulation. The parasite typically spreads when food or water is contaminated with fecal matter, infecting the small intestine and causing prolonged gastrointestinal distress.
The infection triggers explosive watery diarrhea, stomach cramps, severe bloating, nausea, fatigue, and rapid weight loss. Left untreated, symptoms can persist for over a month or recur in cycles.
While the CDC has closed its public health warning, the FDA confirmed that its formal inquiry remains open. “FDA remains confident that all recalled iceberg lettuce related to this specific Cyclospora outbreak is off the market,” the agency said in an update. “Although the outbreak is over, FDA’s outbreak investigation remains ongoing. FDA will continue to work with federal, state, and international partners to complete its investigation and will provide updates as they are available.”
The FDA will continue working with partners to complete its investigation and provide updates as they become available.