FDA Finds Cyclospora at Mexico Lettuce Sites, Closes Probe

On October 2, 2026, the Food and Drug Administration (FDA) concluded its investigation into the multistate Cyclospora outbreak linked to iceberg lettuce from Taylor Farms de Mexico. Investigators detected the microscopic parasite in two environmental samples collected during inspections in Mexico, including a wastewater tank and a farm drainage ditch, but noted that evidence remains insufficient to confirm the exact contamination mechanism. FDA says it remains confident all recalled lettuce from this outbreak is off the market, and it has listed ten prevention activities planned before the 2027 growing season.

Key takeaways:

• The FDA closed its investigation on October 2, 2026, following the Centers for Disease Control and Prevention (CDC) declaring the outbreak over on September 11, 2026.
• Two environmental samples in Mexico tested positive for Cyclospora: an outgoing wastewater tank at a processing plant and a grower drainage ditch.
• The final outbreak toll reached 12,883 illnesses, 570 hospitalizations, and 2 deaths across 21 states.
• FDA listed ten activities planned before the 2027 growing season, including an Outbreak Investigation Report, expert panels on water and wastewater monitoring, and more FSVP inspections of importers.
• CDC says washing alone cannot guarantee Cyclospora removal; cooking produce to at least 158 °F (70 °C) is the option it gives.

What happened

The FDA concluded its traceback and environmental investigation on October 2, 2026, regarding illnesses linked to iceberg lettuce sourced from central Mexico and recalled by Taylor Farms de Mexico. It follows CDC's September 11, 2026 announcement that the outbreak was over.

During onsite inspections in Mexico, FDA investigators sampled water, soil, sediment, and iceberg lettuce. Two samples tested positive for Cyclospora. One came from a tank that held outgoing wastewater from the Taylor Farms de Mexico processing facility. The other came from a drainage ditch of an iceberg lettuce grower identified in FDA's traceback.

Genotyping of both environmental isolates is complete. The FDA reported that it is continuing analyses to determine how these environmental samples correspond to clinical specimens isolated from sick patients. FDA says it remains confident that all recalled iceberg lettuce related to this outbreak is off the market.

What changed

The samples show the parasite was in the environment, but FDA did not name a cause. As the FDA stated, "While there is currently not enough evidence to conclusively determine how contamination occurred in this outbreak, the positive samples show that Cyclospora was present in the environment where lettuce was grown and processed."

FDA has not said whether the environmental genotypes match patient specimens, and it has not announced any enforcement action.

FDA also listed ten activities planned before the 2027 growing season. They include publishing an Outbreak Investigation Report, increasing surveillance of commodities historically associated with Cyclospora, building laboratory capacity in Mexico to test samples there, convening expert panels on worker health and hygiene and on water and wastewater monitoring, working with CDC to align Cyclospora genotyping methods, and increasing Foreign Supplier Verification Program (FSVP) inspections.

For how the outbreak unfolded and what FDA asked of growers when it ended, see Cyclospora Lettuce Outbreak Over: 12,883 Sick. What FDA Wants Now.

Who is affected

FDA and CDC report 12,883 illnesses, 570 hospitalizations, and 2 deaths across 21 states: Arkansas, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Massachusetts, Maine, Michigan, Missouri, Nebraska, New Hampshire, North Carolina, Ohio, Oklahoma, Pennsylvania, Tennessee, Texas, Virginia, and West Virginia.

Illness onset dates spanned the summer, with the final documented onset occurring on August 17, 2026. CDC tracking indicated that during the outbreak's peak prior to public recalls, more than 1,000 infections occurred in a single day, and fewer than 2 infections per day occurred on average in August.

The recalled lettuce reached restaurants and stores. FDA says Taco Bell indicated it is no longer using lettuce from Taylor Farms de Mexico as of July 17, 2026, and recalled Marketside-brand products were sold at select Walmart stores in 15 states.

Nationally, according to FDA's post-outbreak page, CDC reported 19,883 laboratory-confirmed cyclosporiasis cases across the United States as of September 15, 2026. That figure covers all lab-confirmed cases reported this year, and FDA says it includes more than 12,000 cases from this iceberg lettuce outbreak.

What it means for shoppers

FDA says the best-by dates on the recalled lettuce have passed and it should no longer be in stores or restaurants. Cyclospora is still worth understanding, because rinsing is not a reliable fix.

CDC says: "Since washing alone cannot guarantee Cyclospora removal, you can cook produce to a temperature of at least 158 °F (70°C)."

For another produce outbreak that was declared over this year, see Jalapeño Salmonella Outbreak Declared Over at 488 Cases.

The background

Cyclospora is a parasite that causes an intestinal illness called cyclosporiasis. FDA's traceback "identified several farms and a processing facility in Mexico that provided recalled lettuce distributed by Taylor Fresh Foods."

On September 11, 2026, the FDA issued an industry letter signed by Donald A. Prater, DVM, Acting Deputy Commissioner for Food, saying that "while there are practices known to reduce Cyclospora risk, more work must be done." It reminded growers of the Produce Safety Rule (21 CFR Part 112), the Preventive Controls for Human Food rule (21 CFR Part 117), and importer obligations under the Foreign Supplier Verification Program (21 CFR Part 1, Subpart L).

Senior FDA and Mexican public health and agricultural officials met the week of September 8, 2026, to discuss recent outbreaks and ways to strengthen prevention under the U.S.-Mexico Food Safety Partnership.

What to watch next

FDA says its Outbreak Investigation Report will "review the potential factors contributing to the contamination of imported, shredded iceberg lettuce."

FDA also plans more FSVP inspections so importers consider Cyclospora in their hazard analysis, and expert panels on worker health and hygiene and on water and wastewater monitoring.

It is important to state the limits of current scientific findings: existing evidence cannot definitively establish the primary route through which the parasite entered the commercial food stream, and FDA has not said whether the genotypes of the two environmental samples match patient specimens. The specific release date of the upcoming Outbreak Investigation Report has not been disclosed.