CDC Reports Over 4,000 Cyclosporiasis Cases in 41 States Amid Outbreak

The Centers for Disease Control and Prevention has upped the number of cases of cyclosporiasis to more than 4,000 in 41 states.

Cases Continue to Climb

A CDC outbreak update released Tuesday, July 21, reported 4,173 laboratory-confirmed U.S. cases of cyclosporiasis since May 1. More than 7,400 additional cases – many of them in Michigan and Ohio – have not yet been confirmed by laboratories, the CDC said.

There have been 308 hospitalizations and no deaths during the time period. The previous CDC report from July 15 listed 1,645 laboratory confirmed cases and 141 hospitalizations.

The CDC’s case numbers can lag behind those cited by state health officials, due to tracking, verification and reporting processes. The agency expects case counts to continue to rise because there’s typically a six-week reporting lag between an illness and the case being reported to the CDC.

The number of states reporting cases grew to 41 in this latest CDC update, but these may not all be part of ongoing outbreaks. USA TODAY research suggests cases of cyclosporiasis, the infection caused by the microscopic parasite Cyclospora and known to cause severe diarrhea, have been reported in all but four states.

The only states not reporting cyclosporiasis cases, according to the CDC, were: Delaware, Hawaii, Maine, Montana, New Mexico, Oregon, South Carolina, South Dakota and Vermont.

“Cyclosporiasis cases may not be limited to these states with known cases,” according to the CDC update. “The true number of people sick with cyclosporiasis was likely higher than the number reported. This is because some people recover without medical care and are not tested for Cyclospora.”

Who’s Affected

Those with cyclospora infections ranged in age from 2 to 95 years, with a median age of 44. More than half (56%) were female, according to the CDC. The median illness onset date was June 26, 2026 (range from May 1 to July 16).

The CDC also reported 767 travel-linked cases since May 1, with 33 hospitalizations and no deaths tied to contaminated food or water consumed outside the United States.

Taylor Farms Recalls Lettuce Amid Investigation

Produce supplier Taylor Farms on July 17 issued a voluntary recall of iceberg lettuce products as a result of the outbreak and investigation by the CDC, Food and Drug Administration and state health officials. That investigation initially connected the illnesses to lettuce from Taylor Farms de Mexico sold, in part, to Taco Bell locations in five states – Indiana, Kentucky, Michigan, Ohio and West Virginia.

The next day, July 18, the FDA said a Taylor Farms iceberg lettuce sample that was not part of the lettuce recalled by the company had tested positive for cyclospora. Then on July 19, the FDA said that after being reviewed again, the test was found to be a false positive match.

As of July 19, there are no confirmed positive results for samples tested for cyclospora, the FDA said. However, the agency said it is still working with Taylor Farms as it continues to investigate the source of the outbreak and collects and tests samples.

The lettuce recalled was sold in retail stores, served in restaurants and distributed to food service customers. Subsequently, Walmart pulled some bags of Marketside Bagged Iceberg Salad and Shredded Iceberg Salads, distributed by Taylor Farms. The lettuce had been sold in stores in 27 states.

Contributing: Melina Khan, Daniel de Visé and Reuters.

Mike Snider is a national trending news reporter for USA TODAY. You can follow him on Threads, Bluesky, X and email him at mikegsnider & @mikegsnider.bsky.social & @mikesnider & [email protected].