Full story
False Positive, Ongoing Link
Mexico’s Health Minister David Kershenobich said on Tuesday that there is "no evidence as yet to suggest lettuce sourced from Mexico caused a cyclosporiasis outbreak in the U.S." despite a Food and Drug Administration report that traceback data pointed to shredded iceberg lettuce from Taylor Farms locations in central Mexico.
The FDA’s investigation was complicated by conflicting results, including a Saturday report that a sample tested positive for the parasite and a Sunday announcement that the result was a false positive after a re-review of the data.

On Monday, the FDA said its supply chain investigation continues to point to the company’s Mexican facilities as the source of the parasite, while the U.S. Centers for Disease Control and Prevention reported approximately 100 hospitalizations related to the parasitic infection.
The outbreak has been linked to lettuce served at Taco Bell restaurants in Indiana, Kentucky, Michigan, Ohio, and West Virginia, and Taco Bell is owned by Yum Brands.
Mexico’s sanitary regulator Cofepris and agricultural safety body Senasica said in a joint statement on Friday that an interagency technical group is conducting "strictly preventive" inspections and traceability analyses to mitigate health risks.
FDA vs Mexico, and Recall
The Washington Post reported that Kershenobich’s remarks on Tuesday contradicted an FDA assertion of "overwhelming epidemiological data" supporting Taylor Farms’ voluntary recall of iceberg lettuce from central Mexico.
Kershenobich said Mexican health officials have traveled to Guanajuato and taken samples to conduct their own investigation in conjunction with the Centers for Disease Control and Prevention, while the FDA said its traceback investigation and outbreak data continue to converge on shredded iceberg lettuce from Taylor Farms locations in central Mexico.
In a post on X, the FDA said it was confident that shredded iceberg lettuce from Taylor Farms locations in central Mexico is behind illnesses associated with Taco Bell restaurants in Michigan and four other states.
The FDA also said on Monday that its investigation continues to support Taylor Farms’ lettuce as a source, even after Saturday’s positive sample was later deemed a false positive following a re-review by laboratory experts.
Taylor Farms said Sunday that the FDA apologized for the false positive, and the company stated that "FDA has not identified a single positive product test result for Cyclospora".
Scale of Illness and Stakes
The outbreak causes severe diarrhea and other gastrointestinal symptoms, and the CDC has reported approximately 100 hospitalizations related to the parasitic infection.
“The Government of Mexico assured that, to date, there is no evidence confirming that the Cyclospora outbreak reported in the United States is related to the lettuce produced in Guanajuato at Taylor Farms plant”
The Straits Times said the outbreak was linked to lettuce served at Taco Bell restaurants in Indiana, Kentucky, Michigan, Ohio, and West Virginia, while the CBC reported that cyclosporiasis cases have been linked to Yum Brands’ Taco Bell restaurants in Indiana, Kentucky, Ohio, and West Virginia.
In the U.S., the CDC reported more than 1,645 confirmed cases as of July 14, with more than 5,000 more still requiring confirmation, and Michigan had 6,148 linked to the outbreak, according to state officials.
The stakes extend beyond the lab result, because the FDA said the false-positive lab sample "DOES NOT change the basis for FDA’s ongoing outbreak investigation" and that its "traceback investigation and outbreak data continue to converge" on shredded iceberg lettuce from Taylor Farms locations in central Mexico.
Even as Mexico ruled out evidence tying the outbreak to Guanajuato lettuce, the FDA’s investigation and public health actions continued, with Mexico’s Cofepris and Senasica saying the interagency group is conducting "strictly preventive" inspections and traceability analyses.

%2Fhttps%3A%2F%2Fi.s3.glbimg.com%2Fv1%2FAUTH_63b422c2caee4269b8b34177e8876b93%2Finternal_photos%2Fbs%2F2026%2FY%2FQ%2FvThFmBTwSlL6QYgbK7UQ%2Ffoto21bra-301-queima-a2.jpg&w=3840&q=75)

