FDA's Lettuce Test Was Wrong While 1,600+ People Got Explosive Diarrhea

The Test That Wasn't

On Sunday, the FDA announced that a lettuce sample from Taylor Farms that had previously tested positive for cyclospora was, in fact, a false positive. 'Due to the complexity in detection of Cyclospora, FDA laboratory experts re-reviewed the sample results and have concluded that the finding does not represent true amplification,' the agency said in a statement.

So to be clear about the sequence of events: people got sick, the FDA ran tests, the FDA got a positive, the FDA then said the positive wasn't real, and as of Sunday the agency says it has found zero confirmed positive samples from product testing. The parasite responsible for sickening over 1,600 Americans across 34 states remains, at least by the FDA's own lab work, officially unconfirmed in the actual product it almost certainly came from.

This is the food safety system working as designed, apparently.

Taylor Farms Pulled the Lettuce Before the Test Was Even Right

Here's the part that should make you feel both slightly better and significantly worse. Taylor Farms announced on Friday it was voluntarily removing iceberg lettuce sourced from central Mexico even before the false positive was declared false. The company said a traceback investigation pointed to 'a specific independent farm, which represents less than 1% of the U.S.'s iceberg lettuce supply,' and removed all iceberg lettuce from the region indefinitely.

After the FDA's false positive announcement on Sunday, Taylor Farms said in a statement that 'Our thoughts remain with everyone who has fallen ill in this outbreak.' Which is a perfectly reasonable thing to say when you are a lettuce company whose lettuce is at the center of one of the largest cyclospora outbreaks the country has seen in years, even if you technically haven't had a confirmed positive test yet.

The company is cooperating with ongoing investigations. Good for them. The lettuce is still gone from shelves. Also good. The outbreak has still spread to 34 states. Less good.

Taco Bell, Walmart, and a Tour of American Retail Chaos

The CDC identified lettuce supplied to select Taco Bell restaurants as a source of the multistate outbreak on Thursday, more than a month after cases first started appearing. According to the CDC, the iceberg lettuce went to Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia. Taco Bell said Friday it had 'completed removal of affected Taylor Farms lettuce' from its restaurants.

Walmart also announced over the weekend that it had pulled four Marketside bagged iceberg lettuce salad products from stores in more than two dozen states. The company was careful to add that there was 'no indication that products sold in our stores are affected by the current Cyclospora investigations.' Which is exactly the kind of sentence you put out when you are removing a product while also very much not wanting to be associated with a parasite that causes explosive diarrhea.

For anyone keeping score at home: one fast food chain, one of the largest retailers on Earth, and a major produce supplier have all pulled product. The FDA's only confirmed lab result is wrong. And the outbreak keeps growing.

The Numbers the CDC Isn't Keeping Up With

The CDC's official count sits at more than 1,600 people sickened across 34 states since the outbreak first appeared in May. No deaths have been reported. Those are the headline numbers.

But CBS News reports that the CDC's tally lags significantly behind state health departments. Michigan alone tells a different story: the Michigan Department of Health and Human Services reported more than 5,000 confirmed cases as of Friday. Five thousand. In one state. The national figure from the CDC is 1,600-plus total.

This is not a small discrepancy. This is the kind of gap that suggests the official federal count is, at minimum, a dramatic undercount of what is actually happening on the ground. Cyclospora causes long-lasting gastrointestinal illness, not the kind of thing most people immediately associate with a lettuce outbreak, which means plenty of cases almost certainly go unreported entirely. The real number of sick Americans is probably considerably higher than anything the CDC has publicly acknowledged.

What Cyclospora Actually Does to You

Cyclosporiasis is caused by the cyclospora parasite, which is transmitted through contaminated food and water. Public health experts describe the illness as producing long-lasting, watery, and sometimes explosive diarrhea. It is not a brief unpleasantness. Outbreaks typically cluster in late spring and summer and have historically been linked to bagged salads, cilantro, basil, raspberries, snow peas, and green onions.

The fact that this particular outbreak has been traced to iceberg lettuce in Taco Bell restaurants and supermarket salad bags is almost cosmically on-brand for 2025 American food safety. The ingredient doing the damage is not an exotic imported specialty. It is iceberg lettuce. The most boring, ubiquitous, structurally useless salad ingredient in the history of American dining. That is what has sickened over 1,600 people, and possibly far more.