WASHINGTON — On Monday, federal health officials reiterated their focus on identifying lettuce from Taylor Farms as the source of a multistate outbreak involving a diarrhea-causing parasite, even after erroneous test results were briefly shared by the government over the weekend.
According to Food and Drug Administration (FDA) officials, a lab test mistakenly showed a positive result for cyclospora in a sample of lettuce from Taylor Farms. Initially disclosed on the FDA’s website on Saturday, this result was later corrected on Sunday as a false positive.
Federal and state authorities are examining the increasing cases of the parasite, initially connecting the outbreak across five states to lettuce served at Taco Bell locations. On Saturday, Taylor Farms initiated a recall of 25 shredded lettuce and salad mix products distributed under eight brand codes. These products are utilized by multiple U.S. food chains and suppliers.
“The FDA’s traceback investigation and outbreak data continue to point to shredded iceberg lettuce from Taylor Farms’ facilities in central Mexico,” stated Donald Prater, acting food chief of the FDA, to reporters on Monday.
Alongside tracking the lettuce supply chain, FDA personnel have commenced testing produce samples entering the U.S. from the border.
On Monday, FDA officials explained that the erroneous positive result originated from a rapid test for cyclospora. Although the sample initially tested positive for the parasite, it was not included in Taylor Farms’ lettuce recall. The FDA felt it necessary to inform the public of the finding.
A subsequent quality control check revealed the initial positive result was incorrect. The FDA informed Taylor Farms of this correction on Sunday.
Taylor Farms highlighted the updated test results on social media and claimed, “FDA apologized to us.” However, agency officials clarified that no formal apology was issued.
Cyclospora is a microscopic parasite that contaminates food through contact with human feces, often via irrigation or washing with tainted water. Ingestion leads to intestinal illness characterized by “frequent and sometimes explosive bowel movements,” as noted by the CDC.
In 2026, cyclospora has affected at least 1,645 individuals in the U.S., with 141 requiring hospitalization, according to data from the FDA and CDC. They are investigating five clusters of illnesses, including the one linked to Taylor Farms.
FDA’s acting commissioner, Kyle Diamantas, reported that new cases related to the outbreak continue to emerge, with some as recent as last week.
“It’s crucial for us to intervene to ensure contaminated products are kept off the market,” Diamantas stated.
As of Friday, foot traffic at several dining chains decreased compared to day-of-the-week averages from January 1 to July 6, as reported by Placer.ai, which monitors movements via cellphone data.
Taco Bell experienced the most significant decline in foot traffic, dropping 18.9% after federal health officials identified the chain in their cyclosporiasis outbreak investigation. Chopt saw a 14.3% decrease, while both Chipotle and Panera Bread experienced close to a 7% decline. Cava observed a smaller reduction at 4.2%, according to Placer.ai.
Food safety investigators often face challenges in directly linking recalled produce to foodborne illness outbreaks. Many standard tests for food poisoning do not detect cyclospora, and technicians cannot cultivate the parasite in labs, complicating evidence gathering from contaminated produce.
Investigators instead rely on consumer reports, case proximity, timing, and other patterns to draw conclusions.
— Matthew Perrone
AP Business Writer Anne D’Innocenzio contributed from New York.

