FDA Reverses Course on Taylor Farms Cyclospora Finding as Outbreak Spreads Across 34 States

The FDA has walked back its identification of Taylor Farms as the confirmed source of a massive Cyclospora outbreak, announcing that a laboratory test result that appeared to show the parasite in the company's iceberg lettuce was actually a false positive. The agency cited the complexity of detecting Cyclospora as the reason its own experts had to re-review the sample results, ultimately concluding there was no true amplification in the test. Taylor Farms publicly noted that the FDA apologized directly to the company for the error.

Despite the reversal, the outbreak itself is very real and growing. As of mid-July, the CDC had confirmed 1,645 cyclosporiasis cases and 141 hospitalizations across 34 states since May 1, with no confirmed deaths. Michigan alone reported more than 5,000 cases as of July 16 — a number that dwarfs the national confirmed count and suggests significant underreporting nationwide. The CDC's own deputy director of foodborne disease warned that cases are expected to keep rising potentially through the end of August, which marks the end of the seasonal peak for the parasite.

The traceback investigation had previously pointed to shredded iceberg lettuce served at Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia, with 1,644 confirmed cases tied to that chain. Taylor Farms — the world's largest salad producer, supplying restaurants including Chipotle and McDonald's and retailers like Costco, Walmart, and Trader Joe's — voluntarily recalled iceberg lettuce grown in central Mexico and pulled it from its supply chain indefinitely, even before the false positive was discovered. Walmart removed four Marketside-brand bagged salad products from shelves across nearly 30 states as a precaution.

Cyclospora is a particularly difficult pathogen to trace because symptoms — watery diarrhea, cramping, and gas — typically don't appear until roughly a week after exposure, by which time patients often can't identify the specific food responsible. The parasite's genetics are also more complex than those of E. coli or Salmonella, complicating laboratory detection. Epidemiologists suspect contaminated irrigation or washing water at Mexican farms or processing facilities is the most likely source of the outbreak. Health experts are advising consumers to avoid bagged lettuce and pre-washed salads, opt for whole heads, and cook produce to at least 158°F, since washing alone cannot reliably eliminate Cyclospora.