The investigation into the source of a diarrhea outbreak that sickened thousands at Taco Bell restaurants in the US took an unexpected turn. The Food and Drug Administration (FDA) announced that a test on a lettuce sample linked to the outbreak was a false positive.
The FDA had announced on July 18 that the Cyclospora parasite was detected in a product from supplier Taylor Farms. However, the agency said after a re-examination on July 19 that the result was an error. The FDA stated, "The signal does not confirm the actual presence of the parasite and should be considered erroneous."
This development means the exact source of the outbreak has not yet been identified. While no deaths have been recorded from Cyclospora infection, at least 94 people have been hospitalized.
Taylor Farms announced it would voluntarily withdraw all iceberg lettuce imported from central Mexico from the US market. The FDA noted that the sample that tested false positive was not on the company's list of withdrawn products. The agency stressed that a voluntary withdrawal is less comprehensive than a mandatory recall and does not require notifying customers.
The first cases of the illness were detected on May 13. Symptoms can take up to two weeks to appear. Main symptoms include watery diarrhea lasting several days, sudden weight loss, and loss of appetite.
The US Centers for Disease Control and Prevention (CDC) reported that thousands of people have been infected with the Cyclospora parasite. The outbreak is linked to Taylor Farms brand iceberg lettuce sold at Taco Bell restaurants in at least five states. The CDC advised against eating chopped iceberg lettuce at Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia.
Taco Bell announced it had removed all affected Taylor Farms products from its restaurants. Taylor Farms said, "We stopped receiving product from the lot linked to this case, halted shipments of iceberg lettuce from Mexico, notified customers, and continue to work with the FDA, CDC, and state officials."
As case numbers continue to rise, cyclosporiasis has been reported in 31 states, and dozens of people have been hospitalized.
