US Cyclospora Cases Pass 6,700 as Surveillance Cuts Draw Scrutiny

Laboratory-confirmed cases of cyclosporiasis in the United States have passed 6,700 since the start of May, far above the level recorded at the same point last year, as federal investigators work through multiple outbreaks linked to iceberg lettuce. Public health specialists say cuts to surveillance programmes have made the parasite harder to track.

How large is the outbreak?

The Centers for Disease Control and Prevention has recorded 6,707 laboratory-confirmed domestically acquired cases since 1 May, with a median illness onset date of 2 July.

The scale becomes clearer in comparison. In a health advisory issued in mid-July, the agency reported 1,645 confirmed domestic cases against 249 nationally by the same point in 2025. Of those with available information, 141 people, or 9 per cent, were hospitalised. No deaths have been reported.

The CDC has moved to weekly surveillance updates for 2026 because of the increase. Michigan has been hardest hit, with 3,762 cases recorded by mid-July.

Cyclosporiasis is a gastrointestinal illness caused by a microscopic parasite. People contract it through contaminated food or water rather than from each other, and symptoms typically appear about a week after exposure.

What is the source?

Investigators have tied one multistate outbreak across nine states to iceberg lettuce. Taylor Farms recalled iceberg lettuce sourced from central Mexico on 17 July, covering products sold in shops and supplied to restaurants.

A separate five-state cluster was linked to shredded iceberg lettuce served at Taco Bell outlets. The Food and Drug Administration is investigating four distinct outbreaks in total.

Some sources may never be established. Of four cyclospora outbreaks in 2023, three were never traced.

Why is surveillance contested?

Cyclospora was among eight pathogens removed from the tracking list of FoodNet, the CDC’s active surveillance network, following budget reductions. FoodNet covers about 16 per cent of the US population, and participating states are no longer required to report certain infections including listeria.

Remaining systems are passive, depending on states to report cases with no requirement governing how quickly they do so, according to Barbara Kowalcyk of George Washington University. The FDA has not met the inspection targets mandated by Congress since 2018.

Michigan’s chief medical executive, Natasha Bagdasarian, said the state is seeing the consequences of an underfunded public health system.

Debra Houry, who resigned as the CDC’s chief medical officer a year ago over what she described as political interference, argues the country is at a tipping point across vaccine-preventable and foodborne disease alike.

What does the government say?

The Department of Health and Human Services rejects the link. A spokesperson, Emily Hilliard, said FDA investigators were not affected by staffing changes or workforce reductions, and that the president’s budget for the 2027 financial year proposes an additional $33 million for food safety work.

She said the CDC never stopped monitoring illness caused by cyclospora.

The underlying trend predates the current dispute. Recorded cases rose from 537 in 2016 to 4,463 in 2023, the most recent year with complete figures, which means this season’s total represents a sharp acceleration of a decade-long increase.

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