US health officials declare end to largest recorded cyclosporiasis outbreak

Sept 11 (Reuters) – U.S. health officials said Friday that the country’s biggest recorded multistate cyclosporiasis outbreak had ended, following illnesses caused by contaminated iceberg lettuce that affected thousands, although the FDA noted it was continuing to investigate how the parasite got into the food supply.

Federal investigators tied the outbreak to lettuce from central Mexico supplied by Taylor Farms. It led to one of the biggest food recalls in recent years and renewed questions about food-safety oversight for imported produce.

The outbreak also shook consumer confidence, as some shoppers steered clear of raw fruits and vegetables and eating out, reducing foot traffic at restaurants including Taco Bell, Sweetgreen and Chipotle.

Data from the Centers for Disease Control and Prevention showed that 12,883 people across 21 states became ill after consuming lettuce that was contaminated.

It caused 570 hospitalizations and two deaths, and represented more than half of the 19,595 laboratory-confirmed cyclosporiasis cases in the United States reported since May 1.

Before the recall, during the peak of the outbreak, more than 1,000 infections were reported in one day. By August, the CDC said, infections had dropped to an average of fewer than two per day.

Rutgers University food science professor and extension specialist Donald Schaffner said, “I don’t think that we have the necessary tools and technologies to stop outbreaks like this in the future.”

Schaffner urged investment in improved strain-tracking tools and continued funding for parasite research as a way to prevent similar outbreaks.

The FDA stated Friday that it believed all recalled iceberg lettuce connected to the outbreak had been removed from the market. The CDC said the best-by dates for all associated products had expired, meaning the lettuce would no longer be sold in stores or served in restaurants.

On July 17, Taylor Farms recalled all iceberg lettuce it had sourced from central Mexico.

The FDA added that it had finished on-site inspections and gathered samples from lettuce farms and the processing plant in Mexico, with analysis still pending, and that it would keep collaborating with U.S., Mexican and state partners.

Taylor Farms; retailers Walmart, Target and Whole Foods; and restaurant chains Taco Bell (Yum Brands), Chipotle Mexican Grill and Sweetgreen did not reply to Reuters requests for comment.

Federal and state health officials said Michigan, the state most severely affected, reported over 14,000 cases and two deaths connected to the parasite. Ohio and Missouri also recorded thousands of infections linked to contaminated lettuce from Taylor Farms.

The unusually high case count in Michigan was blamed on a large backlog of reports processed in August, underscoring the pressure on a system weakened by federal funding reductions during the Trump administration.

Prior to 2026, the largest cyclosporiasis season ever recorded in the United States occurred in 2019, when about 4,700 illnesses were documented across the country.