FDA confirms Taylor Farms lettuce cyclospora test was false positive

FDA confirms Taylor Farms lettuce cyclospora test was false positive; recall continues despite no confirmed positive samples.

Objective Facts

The FDA announced Sunday that a sample of lettuce from Taylor Farms de Mexico initially reported positive for cyclospora on Saturday was actually a false positive, discovered when laboratory experts re-reviewed the results on July 19, 2026. The FDA stated that due to the complexity in detection of cyclospora, laboratory experts re-reviewed the sample results and concluded that the finding does not represent true amplification and should be considered a false positive. The false positive does not change Taylor Farms' earlier voluntary recall of iceberg lettuce sourced from central Mexico that was distributed to stores in 27 states. Nearly 7,000 cases of cyclosporiasis have been confirmed or are under investigation in the United States since May 1, according to the CDC, with cases reported in at least 34 states. Rutgers food science chair Donald W. Schaffner commended both the Taylor Farms recall and the FDA's willingness to correct its error, while noting that cyclospora testing is inherently difficult and false positives are possible.

Deep Dive

The discovery of the false positive came as FDA laboratory experts re-reviewed lettuce sample results from Taylor Farms as part of an ongoing investigation into cyclospora, a diarrhea-causing microscopic parasite that has sickened thousands of people across the United States. Taylor Farms initiated its recall on Friday after the FDA traced iceberg lettuce from the company's Mexico facility to Taco Bell locations in five states where people became sick before being sickened, prompting Taco Bell to discontinue using the producer for its lettuce. The multistate outbreak began in May 2026 with 1,645 confirmed cases and 5,100 additional suspected cases requiring further testing, exceeding the prior U.S. record of 4,700 annual cases set in 2019. Rutgers University food science chair Donald W. Schaffner explained that testing for cyclospora is difficult and false positives are always possible, noting this case may lead to consumer confusion and uncertainty. Schaffner recommended that regulatory agencies provide more data when announcing positive results, including the false positive rate. Thomas Gremillion, director of food policy at the Consumer Federation of America, confirmed it is "really hard to grow cyclospora in the lab," underscoring the technical challenges involved. According to the CDC, laboratory detection of cyclospora in stool can be challenging even in symptomatic patients, and standard ova and parasite exams might not detect it reliably. The FDA's error, though corrected quickly, highlights the inherent difficulty in detecting a parasite that resists conventional laboratory methods. The false positive discovery does not change Taylor Farms' voluntary recall, with the company continuing to work with the FDA and CDC to ensure products implicated in the outbreak are removed from the market. The FDA has indicated that other brands, restaurants, retailers, or distribution channels could be linked to the outbreak as the investigation continues. Regulatory and scientific experts agree the recall remains prudent given the severity and scale of the outbreak, even without confirmed product contamination—a cautious approach that prevents further potential exposures during the ongoing multi-state investigation.

FDA confirms Taylor Farms lettuce cyclospora test was false positive

FDA confirms Taylor Farms lettuce cyclospora test was false positive; recall continues despite no confirmed positive samples.

Jul 20, 2026

What's Going On

The FDA announced Sunday that a sample of lettuce from Taylor Farms de Mexico initially reported positive for cyclospora was a false positive, discovered when laboratory experts re-reviewed the test results on July 19, 2026.
The false positive was attributed to false amplification, with the FDA noting the complexity in detecting cyclospora.
Despite the false positive finding, Taylor Farms maintains its voluntary recall of iceberg lettuce sourced from central Mexico, distributed to stores in 27 states.
Nearly 7,000 cases of cyclosporiasis have been confirmed or are under investigation in the United States since May 1, according to the CDC, despite no confirmed positive product test results.
Donald W. Schaffner, chair of the department of food science at Rutgers University, said the FDA showed courage in admitting it was wrong about the positive test and praised Taylor Farms' recall decision regardless of the test status.

◆ All Sources (6)

NBC News - Taylor Farms lettuce sample produced false positive for cyclospora, FDA says CBS News - Taylor Farms lettuce sample that tested positive for cyclospora was a false positive, FDA says CNBC - FDA says Taylor Farms cyclospora finding was a false positive Food Safety News - FDA says Cyclospora test on lettuce from Taylor Farms was a false positive; outbreak investigation ongoing Newsweek - Taylor Farms Says FDA Has Apologized Over 'False Positive' Cyclospora Test The Epoch Times - Lettuce Sample That Tested for Cyclospora Was a False Postive: FDA

Objective Deep Dive

Rutgers University food science chair Donald W. Schaffner explained that testing for cyclospora is difficult and false positives are always possible, noting this case may lead to consumer confusion and uncertainty. Schaffner recommended that regulatory agencies provide more data when announcing positive results, including the false positive rate. Thomas Gremillion, director of food policy at the Consumer Federation of America, confirmed it is "really hard to grow cyclospora in the lab," underscoring the technical challenges involved. According to the CDC, laboratory detection of cyclospora in stool can be challenging even in symptomatic patients, and standard ova and parasite exams might not detect it reliably. The FDA's error, though corrected quickly, highlights the inherent difficulty in detecting a parasite that resists conventional laboratory methods.

The false positive discovery does not change Taylor Farms' voluntary recall, with the company continuing to work with the FDA and CDC to ensure products implicated in the outbreak are removed from the market. The FDA has indicated that other brands, restaurants, retailers, or distribution channels could be linked to the outbreak as the investigation continues. Regulatory and scientific experts agree the recall remains prudent given the severity and scale of the outbreak, even without confirmed product contamination—a cautious approach that prevents further potential exposures during the ongoing multi-state investigation.