FDA says Taylor Farms lettuce cyclospora result was false positive

The U.S. Food and Drug Administration said laboratory experts re-checked lettuce sample results from Taylor Farms and concluded the cyclospora finding was a false positive. As of July 19, the agency said there were no confirmed positive sample results for cyclospora.

The reversal came after the FDA said a day earlier that a sample of shredded iceberg lettuce supplied by Taylor Farms had tested positive for the parasite. That finding had sharpened concern around a multistate cyclosporiasis outbreak tied to shredded iceberg lettuce and put the company under immediate scrutiny.

Taylor Farms said on July 17 that it was voluntarily removing all iceberg lettuce sourced from central Mexico from the U.S. market, while saying none of its branded salad products were connected to the illnesses. Taylor Farms and Sysco also pulled iceberg lettuce from central Mexico as the investigation continued, and Wendy's and Chipotle said they were not affected.

The outbreak had already spread through the restaurant and produce supply chain. Investigators linked shredded iceberg lettuce supplied by Taylor Farms to Taco Bell restaurants as part of the outbreak inquiry, adding to pressure on regulators to identify the source quickly.

FDA and Centers for Disease Control and Prevention outbreak pages described the event as a five-state outbreak of cyclospora illnesses linked to iceberg lettuce in July 2026. By July 14, CDC lab-confirmed U.S. cyclosporiasis cases had topped 1,600 and were expected to rise, underscoring how much was at stake as officials tried to balance speed with accuracy.

The false positive left the FDA to correct a finding that had already rippled across the supply chain, affecting a grower, a wholesaler and restaurant brands while consumers faced a changing picture of what might have made them sick.