September 11, 2026
2 min read
Key takeaways:
- The outbreak is over after more than 2 months and thousands of reported illnesses.
- It was traced to a farm in central Mexico that provided lettuce to Taylor Farms
Federal health officials on Friday declared an end to the largest recorded outbreak of cyclosporiasis in United States history.
CDC and FDA websites tracking the outbreak were updated mid-morning to say that it was over after more than 2 months.
The largest recorded outbreak of cyclosporiasis in U.S. history was traced to iceberg lettuce sourced from central Mexico. Image: Adobe Stock
Although the FDA said it would continue investigating the outbreak, which was traced to iceberg lettuce sourced from central Mexico by Taylor Farms, the agencies noted that there has been a sharp decline in cases, and that stores and restaurants should have cleared their shelves of the contaminated lettuce.
“This outbreak has ended,” the CDC page says.
In all, the outbreak included 12,883 cases, 570 hospitalizations and two deaths in 21 states, according to the CDC and FDA.
The actual count is likely higher. Michigan alone has recorded more than 14,700 cases and 366 hospitalizations, according to the state health department.
Cyclosporiasis is caused by Cyclospora, a parasite that spreads to people through food or water that has been contaminated with feces, frequently causing bouts of watery diarrhea. Past outbreaks have been linked to lettuce, raspberries, basil, cilantro and snow peas.
The CDC considers cyclosporiasis “season” to be May through August. As of Sept. 8, the agency says there have been 19,595 cases and 1,043 hospitalizations recorded overall in the U.S. since May 1 this year — a more than 16-fold increase over 2025.
The CDC emphasized that although the outbreak traced to iceberg lettuce is over, the risk for cyclosporiasis from other sources remains.
“At this time, there is no risk of people getting sick with cyclosporiasis from this source,” the agency noted, with emphasis.
Below is a timeline of stories related to the outbreak.
Foodborne parasite sparks surge in cyclosporiasis outbreak
Federal and state health officials announced in July there had been a surge in cases of cyclosporiasis caused by an unknown source. Read more.
Worsening diarrhea outbreak raises questions about changes at CDC
The outbreak raised questions about whether the partial dismantling of a federal surveillance system for foodborne pathogens negatively impacted the response, but a CDC official said tracking of Cyclospora remained “unchanged.” Read more.
Lettuce from Taco Bell is source of diarrhea outbreak, officials confirm
Federal health officials announced in mid-July that there was evidence that shredded lettuce served at Taco Bell restaurants in five states was the source of the outbreak. Read more.
FDA clears air, says Taylor Farms lettuce still linked to cyclosporiasis outbreak
After Taylor Farms announced that the FDA had apologized for a false positive test linking the company’s lettuce to the outbreak, the agency cleared the air, telling reporters that the evidence for the connection was strong. Read more.
Cyclosporiasis outbreak expands to nine states
The full scope of the outbreak began to emerge in late July as federal health officials began linking illnesses in more states to the contaminated lettuce. Read more.
Crypto: The other diarrheal illness that causes summer outbreaks
The outbreak got us thinking about another intestinal pathogen with a similar name that also causes outbreaks of diarrhea in the summer. Read more.
‘High degree of suspicion,’ diagnostics key as Cyclospora outbreak expands
Experts warned that failure to suspect Cyclospora as a cause of diarrheal illness and order the right diagnostic test may be the biggest obstacles to controlling its spread. Read more.
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