CDC closes the lettuce cyclospora outbreak after 12,883 confirmed illnesses

The Centers for Disease Control and Prevention said on 11 September that the multistate cyclospora outbreak linked to shredded iceberg lettuce is over. Recent infections tied to that cluster have fallen sharply, and the lettuce is no longer on sale in shops or restaurants. The cluster sickened 12,883 people across 21 states, with 570 hospital admissions. Two deaths in Michigan involved people who had other serious illnesses.

Investigators traced the lettuce to Taylor Farms production in central Mexico. CDC said there is now no risk of catching this outbreak strain from lettuce still in circulation, because the lots are past their dates. That closure applies only to the named lettuce cluster. FDA's active investigation table still lists other cyclospora clusters whose sources have not been named.

The broader U.S. season, which CDC counts from 1 May, is worse than the single outbreak. As of 8 September the agency had 19,595 laboratory-confirmed domestically acquired cases in 49 states and the District of Columbia, 1,043 hospital stays and two deaths. Median age was 46. Fifty-six percent of patients were female. Median symptom onset was 8 July. Another 9,355 confirmed cases still need travel interviews, and CDC knows of at least 6,149 further cases that are unconfirmed or waiting on paperwork.

Cyclospora cayetanensis is a parasite. People swallow it on food or in water contaminated with faeces. It produces watery diarrhoea, cramps, fatigue and weight loss that can last weeks if untreated. The standard drug is trimethoprim-sulfamethoxazole. Many patients never get a laboratory test, which is why CDC says the true number of sick people is higher than the official count. The reporting lag is about six weeks.

The United States has run a cyclospora season every summer for years, usually tied to imported herbs, berries or salad greens. The 2026 lettuce cluster is the largest recorded multistate outbreak of the illness. It accounted for more than half of this season's confirmed domestic cases. That share is the information gain. A single commodity, from a single large processor, drove the worst year on the books.

Taylor Farms is a major supplier to restaurants and bagged-salad lines. Once a lot is in food service, tracing who ate which bag becomes a reconstruction from invoices and memory. CDC's decision to close the outbreak rests on two observables: the product is gone, and the epidemic curve for that cluster has dropped. It does not mean the parasite is gone from American kitchens. It means this pipeline has been cut.

Farmers and buyers will read the file as a sourcing problem. Iceberg from one Mexican operation seeded 21 states. Import inspection does not catch a parasite that is not in every head. The practical control is upstream water and sanitation at the farm, plus faster withdrawal when the first state labs light up. Those steps failed early enough this summer to put 12,883 confirmed names on a list.

CDC will keep adding late reports through autumn because of the six-week lag. The closed label on the lettuce outbreak should still hold if no new lot is found. The open question is the other clusters FDA has not yet sourced. Until those are named, 2026 remains the season in which one salad ingredient set a record and several others are still unsolved.