Cyclospora outbreak over after record U.S. lettuce-linked illnesses

The cyclospora outbreak over announcement applies to the record 21-state outbreak linked to recalled iceberg lettuce, the Centers for Disease Control and Prevention said on September 11. CDC said consumers no longer face a risk from that specific source because the related lettuce is off the market, while federal investigators continue to examine how contamination occurred.

Nearly 13,000 reported illnesses were connected to the multistate outbreak, according to reporting by CBS News and PBS NewsHour. The implicated product was recalled shredded or processed iceberg lettuce sourced from central Mexico and associated with Taylor Farms de Mexico, according to those reports.

The declaration closes the largest recorded U.S. outbreak of this kind, but it does not mean the broader 2026 cyclosporiasis season or every investigation has ended. CDC surveillance data show 19,595 laboratory-confirmed U.S.-acquired cases reported from May 1 through September 8, including 1,043 hospitalizations and two deaths. Cases were reported from 49 states and Washington, D.C.

What does it mean that the cyclospora outbreak is over?

CDC’s finding concerns the identified lettuce-linked outbreak, rather than all infections reported nationally. The agency said its season-wide total includes both cases from the ended multistate outbreak and cases that have not been connected to it.

CDC warns that the figures remain preliminary. It can take about six weeks from symptom onset for a case report to reach the agency, and the true illness count is likely higher because some people recover without seeking medical care or testing. CDC also listed 9,355 laboratory-confirmed reports requiring further work to establish whether infection was acquired in the United States or during travel, alongside at least 6,149 additional reports that were not laboratory-confirmed or were pending interview and submission.

Cyclosporiasis is a gastrointestinal infection caused by the parasite Cyclospora cayetanensis, CDC says. The U.S. seasonal reporting period runs from May 1 through August 31, although the agency continues receiving and investigating reports after that window because of the reporting delay.

What remains under investigation?

The Food and Drug Administration is continuing its investigation into infections associated with the recalled iceberg lettuce, CBS News reported. The precise route of contamination has not been determined. FDA had completed on-site inspections and sample collection at Mexican iceberg-lettuce growers and the processing facility, but the samples were still awaiting analysis, according to CBS News and PBS NewsHour.

In July, Taylor Farms recalled iceberg lettuce, and Taco Bell removed the product from its restaurants, CNBC reported. The end of the outbreak therefore reflects the removal and expiry of the implicated products, rather than a final finding on the contamination’s origin.

This story draws on original reporting from CNBC.