Massive cyclosporiasis outbreak linked to four more states

ATLANTA — Nine states now have related cases of diarrheal illness caused by iceberg lettuce contaminated with the microscopic cyclospora parasite, according to the U.S. Centers for Disease Control and Prevention.

Four more states — Illinois, Kansas, Oklahoma and Pennsylvania — have been added to the outbreak that already includes Indiana, Kentucky, Michigan, Ohio and West Virginia.

The additional states were first reported by The Washington Post.

Data continue to show that contaminated iceberg lettuce from Taylor Farms de Mexico made people sick, the CDC said. So far, the agency has tallied 1,947 people infected with cyclospora who also reported eating at Taco Bell in the nine states. Illnesses in the outbreak tied to iceberg lettuce began on June 22 and have continued through July 20, the CDC said.

But health departments in these nine states have reported more than 12,000 cases of cyclosporiasis so far this summer, with the majority of those cases in Michigan.

Michigan health officials have said it's possible that some of their cases are linked to additional sources. Not everyone they've interviewed could remember eating lettuce.

Detailed interviews with patients and traceback information have helped health officials home in on iceberg lettuce from central Mexico as the likely source. Investigators with the U.S. Food and Drug Administration, as well as health authorities in Mexico, are actively investigating what may have caused the contamination. Taylor Farms has recalled shredded lettuce processed in central Mexico that was shipped to restaurants, food services and retailers in 27 states.

Cyclosporiasis cases have been identified in dozens of states this summer, and the CDC has said it's investigating several clusters, and not all are linked to the same source.

The total number of cyclosporiasis cases reported this year in the U.S. is also higher than usual. There were more than 4,500 cases in 2023 and more than 3,500 cases in 2024, according to federal officials. But there have already been thousands more reported this year, with at least a month left in the season.

It can take up to two weeks for symptoms of cyclosporiasis to appear after consuming contaminated food or water. Symptoms include watery diarrhea, loss of appetite, weight loss, cramping, bloating and increased gas, nausea and fatigue, and people who become ill may have symptoms for weeks.

Related topics