FDA withdraws suspicion against salad supplier: Cyclospora outbreak in the US remains unsolved

On social media, the authority wrote: "this 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." The recommendation not to eat iceberg lettuce from Taco Bell locations in five states remains in place.

Scale of the outbreak

According to the US health authority Centers for Disease Control and Prevention (CDC), more than 1,600 sick individuals reported having eaten at Taco Bell restaurant locations in five US states. Another 5,100 cases were still being investigated as of mid-week. 94 people had been hospitalized; no one had died from the illness as of the latest report.

The five affected states are Indiana, Kentucky, Michigan, Ohio, and West Virginia. In interviews, many of those sickened reported having eaten iceberg lettuce at Taco Bell locations. "Do not eat chopped iceberg lettuce from Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia," the authority warned.

Recall and supply chains

Investigations identified a single supplier from Mexico from which the fast-food chain had sourced the lettuce. On July 17, Taylor Farms subsequently voluntarily recalled all iceberg lettuce grown and processed in central Mexico. The company announced on Monday that going forward, for the remainder of the season, it would be "no longer sourcing iceberg lettuce grown in central Mexico for the remainder of the growing season." Taco Bell also stated that it would no longer use the recalled lettuce from Taylor Farms de Mexico.

Iceberg lettuce products from Taylor Farms were, according to authorities, in circulation in 27 states as well as in Walmart locations in 15 states. Cyclospora infects the small intestine and causes watery diarrhea with frequent, sometimes forceful bowel movements. Because the illness often goes unrecognized or unreported, the actual number of cases is likely to be significantly higher.

Transmission and recommendations

According to the CDC, the parasite is typically not transmitted from person to person, but rather through food or water contaminated with feces. Transmission routes include drinking water, bathing water, or water that comes into contact with fruits and vegetables. Health authorities recommend washing lettuce thoroughly with water before consumption and heating vegetables to 158°F (approximately 70°C) to reduce the risk of infection.

Investigations continue

Since the 1990s, Cyclosporiasis outbreaks have occurred regularly in the summer, but none has reached the scale of the current event. Donald Schaffner, a microbiologist at Rutgers University, stated on the matter: "Just because you're sick with Cyclospora right now doesn't mean that you're part of this cluster of cases that have an epicenter in Michigan and Ohio." A Cyclospora illness does not automatically mean being part of the outbreak cluster. Schaffner added: "Sometimes we can figure out what's causing it, and sometimes we can't." Sometimes investigators can find the source, sometimes not.

As of July 19, 2026, there are no confirmed positive test results for Cyclospora. The FDA continues to test lettuce samples as well as products at the US southern border, with no positive findings so far. The actual source of infection of the largest Cyclospora outbreak in the US in decades therefore remains unresolved for now.