If you’ve spent the last two weeks watching ‘explosive diarrhea’ trend across the country and thought that can’t possibly be a real news category — it is now, and thousands of very unlucky people can confirm it.
A foodborne illness called cyclosporiasis has swept through more than 30 states this summer, and as of Thursday night federal investigators have finally pinned down a source most of us order without thinking twice: shredded iceberg lettuce.
If your first guess was “some kind of food poisoning,” you’re close.
But this isn’t the usual salmonella-or-E. coli story.
Cyclosporiasis is caused by a microscopic parasite, Cyclospora cayetanensis, that burrows into your small intestine and — in the CDC’s own delicate clinical phrasing — produces watery, frequent, and “sometimes explosive” bowel movements.
So: foodborne, yes.
A germ, no.
A parasite, and a genuinely miserable one.
What Cyclospora actually does to you
Once the parasite reaches your gut, it starts reproducing and stops your intestines from absorbing fluid properly — so everything you eat and drink runs straight through you.
Beyond the diarrhea, symptoms include bloating, nausea, cramping, loss of appetite, weight loss, and a flu-like wave of fatigue and body aches that can make you feel like you’re coming down with something before the real fun starts.
Two things make this parasite especially sneaky.
First, it’s slow: symptoms usually take about a week to appear — sometimes as little as two days, sometimes more than two weeks after you eat the contaminated food.
By then, whatever made you sick is long gone from your fridge and probably off store shelves entirely.
Second, it doesn’t spread from person to person — you can only get it from contaminated food or water — which is small comfort when you’re the one clutching the sink.
Many otherwise healthy people recover on their own; doctors can treat it with antibiotics, and dehydration is the real danger, especially for young children, older adults, and anyone with a weakened immune system.
The scale: one of the biggest outbreaks in years
The numbers are ugly.
As of July 15, the CDC had confirmed 1,645 domestically acquired cases and was investigating more than 5,100 others — roughly 7,000 people all told, making this one of the largest foodborne outbreaks in the U.S. in years.
For comparison, the CDC logged just 249 confirmed cases at this point last year.
Michigan has taken the worst of it, with the state health department reporting more than 4,300 cases — a figure that badly outpaces the CDC’s national tally, because the agency’s numbers lag weeks behind what states are seeing.
Nationwide, about 141 people have been hospitalized, and no deaths have been reported.
The source: Taco Bell lettuce, a supplier from Mexico, and a familiar name
After weeks of investigators coming up empty, the FDA and CDC named a source late Thursday: shredded iceberg lettuce served at Taco Bell locations in five states — Indiana, Kentucky, Michigan, Ohio, and West Virginia.
More than 1,600 sick people in that cluster reported eating at Taco Bell, and when Michigan officials dug into what they’d ordered, about 90 percent had eaten iceberg lettuce.
Regulators traced it to a single supplier of Mexican-grown lettuce.
They didn’t name the company publicly, but people familiar with the investigation identified it to CNN and the Washington Post as Taylor Farms — a name worth remembering, since Taylor Farms produce has been tied to past outbreaks, including E. coli in slivered onions in 2024 and cyclospora in lettuce back in 2013.
Taco Bell, owned by Yum Brands, has committed to stop using lettuce from that supplier.
If you’re in one of those five states, the guidance is simple: don’t eat the shredded iceberg lettuce at Taco Bell until this clears.
One caveat before you swear off tacos forever
Here’s the part that’s easy to lose in the panic: this is almost certainly not one giant nationwide outbreak.
The FDA is actually chasing several separate cyclospora outbreaks at once, and the Taco Bell cluster is a regional one centered in the Midwest.
Plenty of the thousands who got sick this summer never set foot in a Taco Bell, which is why investigators are now racing to find out where else that lettuce went.
Cyclospora cases also spike every warm-weather season and have been climbing for a decade — from 537 cases in 2016 to more than 4,400 in 2023.
Who dropped the ball — and the fight over CDC cuts
The uncomfortable backdrop to all of this is that the outbreak comes at exactly the moment the Trump-Vance administration has been gutting the federal food-safety workforce.
And that has kicked off a real fight over whether those cuts made this worse.
Some experts say plainly that they did.
Barbara Kowalcyk, a food-safety director at George Washington University, told The Guardian she believes the funding cuts have hampered the response, because thin staffing slows down the patient interviews that are the whole ballgame when you’re trying to trace a parasite with a two-week head start.
Sen. Amy Klobuchar (D-MN) sent the CDC a July 14 letter urging it to restore FoodNet and other food-safety programs, warning that the cuts are eroding the country’s ability to catch outbreaks at all.
In fairness, not every expert agrees the cuts were decisive here.
A former CDC official told the Washington Post the reductions likely had little effect on this specific investigation, since cyclospora remains a nationally reportable disease and the FoodNet program that got trimmed was never designed to detect outbreaks in the first place.
That’s a fair point — and it doesn’t let anyone off the hook.
Because what’s not in dispute is that the CDC’s own case data lagged so far behind the states that Michigan was sounding the alarm nearly two weeks before the CDC issued its national alert, leaving reporters and the public working from confusing, out-of-date numbers during the exact window when clear information mattered most.
The cuts didn’t cause a parasite to grow in a lettuce field in Mexico.
But they’ve quietly hollowed out the early-warning system Americans rely on to catch the next one — and a slower, blinder public-health apparatus is a choice, not an accident.
What to do right now
You did not, in fact, need to look it up yourself.
But now you know: it’s a parasite, it was in the lettuce, and the people whose job it is to catch these things are working with a lot less than they used to.
