The Food and Drug Administration has reversed a key finding in its investigation of a major cyclospora outbreak, acknowledging that a Taylor Farms lettuce sample initially reported as contaminated actually produced a false positive.
FDA officials announced Saturday that shredded iceberg lettuce supplied by Taylor Farms de Mexico had tested positive for the diarrhea-causing parasite. One day later, however, the agency said laboratory experts had reviewed the results again and determined that “the finding does not represent true amplification and should be considered a false positive.”
As of Sunday, the FDA had not confirmed cyclospora in any of the product samples collected during the investigation.
Taylor Farms said the agency privately acknowledged its error.
“Today, FDA apologized to us,” the company said Sunday. “Today, we were informed that FDA made a mistake, and this was a false positive.”
The reversal does not end the investigation or cancel the company’s voluntary recall. The FDA continues to advise consumers not to eat the affected iceberg lettuce, citing epidemiological and supply-chain evidence that points to Taylor Farms de Mexico.
The FDA said its traceback investigation converged on Taylor Farms as the supplier of shredded iceberg lettuce served at Taco Bell locations where infected customers reported eating before becoming sick. Among 190 patients whose food histories were examined by Michigan officials, 90 percent reported eating iceberg lettuce.
Taylor Farms voluntarily recalled all iceberg lettuce grown and processed in central Mexico on July 17 “in an abundance of caution,” according to the company. The recall is limited to that lettuce, and Taylor Farms said none of its other products are affected.
The recalled lettuce was distributed between June 29 and July 16 across 27 states. It includes certain Marketside iceberg salad and shredded lettuce products sold at Walmart, along with products supplied to restaurants and other food-service customers. Consumers can consult the FDA’s complete recall notice for affected brands, package sizes, lot numbers and use-by dates.
Taco Bell announced Friday that it had removed the implicated Taylor Farms lettuce from its restaurants nationwide.
“Based on ongoing conversations with public health officials, and out of an abundance of caution, Taco Bell worked swiftly to voluntarily remove the product from restaurants,” the company said in a public statement.
Despite the laboratory reversal, the Centers for Disease Control and Prevention continues to link the five-state outbreak to shredded iceberg lettuce served at certain Taco Bell locations in Indiana, Kentucky, Michigan, Ohio and West Virginia. The CDC reported more than 1,644 illnesses connected to that outbreak, including 94 hospitalizations and no deaths.
Those cases are part of a broader surge in cyclosporiasis recorded across the country. In a July 14 health advisory, the CDC said it had received reports of 1,645 confirmed domestically acquired cases across 34 states since May 1. More than 5,100 additional reports still required further analysis, meaning they had not yet been confirmed as domestic cyclospora infections.
Three Ohio residents have also filed lawsuits against Taco Bell and Taylor Farms, alleging they became ill after eating meals containing lettuce at the fast-food chain. The claims have not yet been adjudicated, and the FDA’s revised laboratory finding could become significant as those cases move forward.
Cyclospora is a microscopic parasite typically spread through food or water contaminated with fecal matter. It can cause prolonged watery diarrhea, stomach cramps, nausea, fatigue, loss of appetite and weight loss. Symptoms may persist for weeks or return after appearing to subside.
Federal officials say the investigation remains open and additional product samples are being collected and analyzed. Consumers are still being instructed to discard or return recalled lettuce rather than eat it.
READ NEXT: Body Found At Rental Property Owned By Ayanna Pressley’s Husband As Homicide Investigation Begins
