The CDC is tracking a nationwide surge of cyclosporiasis this summer, and the case count has now climbed past 11,500 for 2026.
As of a July 21 update, the CDC had recorded 4,173 laboratory-confirmed cases of cyclosporiasis acquired in the United States since May 1.
The agency says it is also aware of more than 7,400 unconfirmed cases that are still under investigation, mostly reported from Michigan and Ohio.
Together, those figures push the national total above 11,500. These cases have been confirmed in 41 states, with at least 308 people hospitalized. No deaths were reported.
The CDC warned that cyclospora cases are significantly higher this year than in 2025, and has begun posting weekly surveillance updates to keep the public updated on the surge.
Cyclosporiasis season in the U.S. typically runs from May 1 through August 31, so health officials expect the case-count to keep climbing, since can take up to 6 weeks for a case to be confirmed and reported.
A large share of the confirmed illnesses is tied to one fast-moving outbreak. The FDA and the CDC have linked shredded iceberg lettuce that was served at Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia to 1,644 Cyclospora infections, including 94 hospitalizations. Illnesses in that cluster began between May 13 and July 13.
The FDA’s trace-back investigation pointed to a single supplier, Taylor Farms de Mexico, which grew the lettuce in central Mexico. Taco Bell has since removed shredded lettuce from its restaurants nationwide.
On July 17, Taylor Farms recalled all iceberg lettuce that it sourced from central Mexico, and the FDA posted the notice the following day. The lettuce reached restaurants and grocery stores in 27 states, including bagged lettuce products that were sold under the Marketside brand at Walmart:
- Marketside Iceberg Salad, 12 oz and 24 oz (Best if Used By July 18 to August 3, 2026)
- Marketside Shredded Lettuce, 8 oz and 16 oz (Best if Used By July 18 to August 3, 2026)
So far, no lettuce sample has tested positive for the parasite. An early presumptive result was later ruled a false positive, and as of July 19 the FDA said its testing had not confirmed Cyclospora in any product. However, the FDA has not withdrawn its traceback finding or its warning against the recalled lettuce. Taylor Farms has described the recall as a precaution.
Cyclosporiasis spreads in human feces from people who are infected with a microscopic parasite, Cyclospora cayetanensis. It spreads through contaminated food or water.
Symptoms usually appear about a week after exposure. The symptoms often begin with watery diarrhea, loss of appetite, cramping, bloating, nausea, and fatigue. Without treatment, the infection can last a month or more, or seem to go away and return later.
Consumers who were diagnosed with cyclosporiasis after eating the recalled lettuce may have legal options, and a product liability attorney can advise them on their rights.