The Food and Drug Administration said a sample of iceberg lettuce from Taylor Farms that had earlier tested positive for cyclospora was a false positive after a laboratory re-review, and the Centers for Disease Control and Prevention confirmed late Thursday that shredded iceberg lettuce served at Taco Bell restaurants in Indiana, Kentucky, Michigan, Ohio and West Virginia is a source of a multistate outbreak; Taylor Fresh Foods said it is voluntarily removing all iceberg lettuce sourced from central Mexico, and an FDA recall notice said the shredded lettuce was sold in 27 states between June 29 and July 16, warning consumers not to eat that product.
Acting FDA Deputy Commissioner for Food Donald Prater said Monday that the sample initially flagged as positive was not part of the current recall and that its re-evaluation "does not alter the data supporting the outbreak advisory that prompted the current voluntary recall."
As of Saturday, the CDC had confirmed more than 1,600 cases in people in Indiana, Kentucky, Michigan, Ohio and West Virginia, and at least 1,644 people have fallen ill overall, though officials say the true number is likely higher. Health officials said there are a growing number of suspected cases in the thousands, 94 people have been hospitalized and there have been no deaths reported.
Taylor Farms voluntarily recalled potentially affected shredded iceberg lettuce sourced from central Mexico on July 17 after federal investigators established a link between lettuce served at some Taco Bell restaurants and Taylor Farms de Mexico; the company has said the FDA identified a single independent farm, accounting for less than 1% of the U.S. iceberg lettuce supply, as a potential source. Taylor Farms said the FDA had "apologized to us," but an FDA official on a call Monday disputed that the agency had issued an official apology.
FDA officials have stressed that tracking Cyclospora in food is challenging because fresh produce has a short shelf-life and infections can take weeks to show up. "Test results are difficult to obtain, and most of the time, our traceback and epidemiologic information are what allows us to determine the source of the outbreak," Prater said, and Acting FDA Commissioner Kyle Diamantas said the investigation is ongoing, "including into other potential sources and commodities for other clusters of illnesses."
Food safety experts say recalls are inevitable for a supplier the size of Taylor Farms. Jennifer McEntire, founder of food safety consulting firm Food Safety Strategy, said, "Nothing about this outbreak is typical," and noted the scale of illnesses has surprised experts.
Restaurant and consumer effects have been pronounced: Taco Bell said it removed the affected lettuce from its restaurants, and analysts at Placer.ai found foot traffic at Taco Bell restaurants across the U.S. was down 19% on Friday compared with the average number of Friday visits for the rest of the year. Sandra Eskin, CEO of Stop Foodborne Illness and the former deputy undersecretary of food safety at the U.S. Department of Agriculture, said Taco Bell's preemptive removals were a good move.
The FDA said it has continued testing lettuce samples and is testing produce at the southern border to check for Cyclospora, but so far none of that testing has turned up any positives. The agency also clarified on social media that the false-positive lab sample "does not change the basis for FDA's ongoing outbreak investigation or the overwhelming epidemiological data supporting the current voluntary recall by Taylor Farms."
An FDA recall notice said some iceberg lettuce products were distributed to Walmart stores in 15 states, and health officials urged consumers to discard any recalled iceberg lettuce distributed by Taylor Fresh Foods.
On Monday Taylor Farms said it had voluntarily recalled all iceberg lettuce grown and processed in central Mexico on July 17 and clarified that it is "no longer sourcing iceberg lettuce grown in central Mexico for the remainder of the growing season." The company said the FDA apologized and emphasized that "FDA has not identified a single positive product test result for Cyclospora."
The Cyclospora parasite causes diarrhea, fatigue and nausea, and health officials said cooking produce to 158 F and thoroughly washing produce with water can help reduce the risk of cyclosporiasis. Donald Schaffner, a microbiologist at Rutgers University, said clusters of Cyclospora illness are often separate and unrelated and that exposures can come from other sources such as drinking or recreational water or water used on produce.