FDA finds cyclospora parasite at Taylor Farms Mexico sites linked to lettuce outbreak

US health inspectors have found the cyclospora parasite at a Taylor Farms facility and an associated grower in Mexico, concluding an investigation into the largest outbreak of its kind in US history.

The US Food and Drug Administration (FDA) said on Friday that its inspectors detected the microscopic parasite in a wastewater tank at the Taylor Farms de Mexico processing plant, and in a drainage ditch at a nearby farm in Guanajuato. The agency said the findings provide "strong epidemiological data" linking the facility to the massive outbreak that swept across the US.

The announcement comes just weeks after the Centers for Disease Control and Prevention (CDC) declared an end to the historic outbreak. The parasite infected nearly 13,000 people across 21 US states, leading to 570 hospitalisations and two deaths.

Where the parasite was found

FDA inspectors detected cyclospora in two environmental locations in Mexico: a wastewater tank at the Taylor Farms processing plant and a drainage ditch used for lettuce cultivation at a nearby farm. It remains unclear how the lettuce itself originally became contaminated.

Taylor Farms, a major US produce company, said in a statement that the contamination cited by the FDA was linked to an independent grower "who is no longer part of our supplier program".

The company added that its facility in central Mexico remains closed while its research team works to implement enhanced safety protocols from the fields to the processing plant.

The FDA's inspection of the Guanajuato site, which took place over six weeks ago, was its first visit to the facility in more than seven years. International food safety inspections by the US agency had fallen sharply following the Covid-19 pandemic.

Discord between US and Mexican regulators

The FDA's findings contrast directly with those of Mexican regulators. Mexico's food safety authority conducted its own investigation and reported that cyclospora was not detected in the lettuce or water at the facility.

That declaration came shortly after the FDA was forced to retract a faulty border test result that had incorrectly flagged a lettuce sample from Taylor Farms. Despite the earlier error, US officials say the environmental samples collected inside Mexico provide strong evidence linking the facility to the outbreak.

What is cyclospora?

Cyclospora cayetanensis is a microscopic parasite that causes cyclosporiasis, an intestinal illness marked by severe, watery diarrhoea, stomach cramps, bloating, gas, and weight loss.

While less common than bacterial foodborne illnesses caused by salmonella or E. coli, cyclosporiasis can be highly disruptive and often requires specific antibiotic treatment to resolve.