Cyclospora found at Mexican farmed linked to lettuce outbreak, FDA says

The Food and Drug Administration said Friday that its inspectors detected cyclospora at the Mexican farm blamed for the largest foodborne illness outbreak of the parasite in U.S. history.

Despite the finding, the FDA said it’s unclear how the parasite got into lettuce at Taylor Farms’ facility. The agency has now closed its investigation into the outbreak, which led to nearly 13,000 cases of diarrhea and other illnesses across the U.S.

The announcement comes more than six weeks after the agency sent its investigators to the farm in Guanajuato, Mexico. The visit was the agency’s first time there in more than seven years following a steep drop in international food safety inspections after the COVID-19 pandemic.

FDA inspectors said Friday they found cyclospora in two places: a wastewater tank and a drainage ditch used for lettuce cultivation. While it’s unclear how the contamination took place, the FDA said the samples provide “strong epidemiological data” linking the outbreak to the Taylor Farms site.

In a separate statement, Taylor Farms attributed the contamination cited by FDA to an independent grower “who is no longer part of our supplier program.”

“Our facility remains closed in central Mexico as we work with our research team to implement enhanced safety protocols from the field to the facility,” the company said.

U.S. officials last month declared the outbreak had ended.

Cyclospora is a microscopic parasite that commonly causes watery diarrhea “with frequent and sometimes explosive bowel movements,” according to the CDC. The illness, called cyclosporiasis, is less common than foodborne illnesses caused by other germs, including salmonella and E. coli.

The parasite is spread through human feces, and it still isn’t clear how sewage could have contaminated enough food to sicken so many people.

Regulators from Mexico’s food safety authority announced in August that their own investigation did not detect cyclospora in the lettuce or water at the facility. That conclusion came days after the FDA was forced to retract a faulty test result that had incorrectly identified cyclospora in a sample of lettuce from Taylor Farms collected at the border.

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