Cyclospora outbreak spreads as FDA investigates new cluster

A multistate outbreak of cyclosporiasis linked to shredded iceberg lettuce has widened to nine states, while federal officials are investigating another cyclospora outbreak tied to an as-yet unidentified product.

The Centers for Disease Control and Prevention said Friday that outbreaks in Illinois, Kansas, Oklahoma and Pennsylvania have now been connected to cases in Indiana, Kentucky, Ohio, West Virginia and Michigan. The CDC has confirmed 1,947 cases in those nine states.

The broader picture remains complicated. The Food and Drug Administration said Thursday it had identified a new cyclospora outbreak stemming from an unspecified product, and a spokesperson told CBS News the agency had begun a traceback investigation to follow a potentially contaminated food through the supply chain.

“This is an active investigation,” the spokesperson said. “We will provide updates as they become available.”

Federal officials have already linked one major outbreak to shredded iceberg lettuce sourced from Taylor Farms de Mexico. The FDA said last week that the lettuce was the likely source, and the company voluntarily recalled the product from the U.S. market.

“We know it went to many states, to many points of sale,” said Kari Irvin, deputy director of the FDA’s Coordinated Outbreak Response and Evaluation Network. Irvin said the FDA is watching confirmed CDC case counts closely “because it will help tell us if the recall is enough, that they’ve recovered all products that need to be removed from the market.”

Investigators connected the lettuce to illnesses after interviewing people who got sick. Many reported eating at Taco Bell in June, before larger waves of cases emerged. The restaurant chain removed lettuce from its menu before the Taylor Farms recall.

The CDC said the newly connected states do not necessarily show that infections are accelerating. Instead, officials said, the expanded list reflects better information from interviews and investigations.

“We’re getting more complete case data that covers the range of the outbreak,” said Gwen Biggerstaff, deputy director of the CDC’s department of foodborne, waterborne and environmental diseases. “States are completing interviews with people, and we’re filling in the data.”

Irvin said FDA investigators are still examining whether other growers may have contributed. “The data that we have now really continues to home in on growers that were already identified,” she said.

Cyclospora is a microscopic parasite that can contaminate food or water and cause cyclosporiasis, a gastrointestinal illness. The parasite can cling to fresh produce, including fruits, vegetables and herbs, and is difficult to wash away. The CDC says it spreads through water contaminated with human feces. CBS News reported that symptoms can include severe and sometimes “explosive” diarrhea. Cooking can kill the parasite, but health officials say washing produce alone is not enough.

Iceberg lettuce from Taylor Farms is unlikely to explain all reported illnesses. NBC News reported that tallies from the CDC and state health departments show nearly 12,000 confirmed or suspected cases nationwide. Michigan has reported the most, with nearly 8,000 infections. Ohio has 2,596 cases, and the CDC has sent three staff members there to assist the state investigation.

Other states have reported hundreds of cases that have not been linked so far to the multistate outbreaks. New York has had 632 cases since May, and North Carolina has reported 561 in the same period. Preliminary investigations in North Carolina suggest parsley and cilantro could be behind those cases.

CBS News reported that the CDC had received reports of 1,645 confirmed cases since May 1, including 141 hospitalizations, and was aware of more than 5,100 additional cases needing further analysis. State health departments have reported higher counts in some places, including Michigan, where officials said Thursday there were 7,664 confirmed cases.

“Because cyclosporiasis is often underdiagnosed and underreported, the true number of illnesses is likely higher than what has been reported,” the CDC said.

The FDA said it also is investigating a separate outbreak with at least 10 cases, while another outbreak has ended but remains under investigation. Irvin said the agency has seen different “signals” of possible sources. “We have multiple investigations of cyclospora open,” she said.