Explosive Diarrhea Won’t Disappear: The Cyclospora Outbreak Gets Personal

Three weeks ago, we thought we had written enough about the Cyclospora outbreak. We were wrong. Last Saturday we went to a party with dear friends we have known for more than 50 years. A couple of weeks earlier, while vacationing at the North Carolina coast, both had developed a nasty case of cyclosporiasis. They weren’t mildly inconvenienced. This microscopic parasite knocked them for a loop.

Both tested positive for Cyclospora cayetanensis. They had not eaten at Taco Bell, the restaurant chain that initially attracted so much attention during this outbreak. What they did remember was making a large salad with produce they had purchased at a local supermarket.

We cannot say that salad caused their illnesses. Neither can their doctors. But their experience is a vivid reminder that the huge outbreak associated with recalled iceberg lettuce represents only part of this summer’s cyclosporiasis story. For us, a news story that seemed far away suddenly became personal.

When Treatment Becomes Challenging

Our friend is still suffering. To make matters worse, she has a genuine allergy to sulfonamide antibiotics.

That matters enormously because the one medicine considered reliably effective against Cyclospora is a sulfa-containing drug. Here is what we wrote three weeks ago:

“Trimethoprim-sulfamethoxazole, abbreviated TMP-SMX and sold under the brand names Bactrim and/or Septra, is the treatment of choice for cyclosporiasis.”

Tricia shared this experience with TMP-SMZ:

“I ate at Taco Bell in North Carolina on July 1st and had an immediate reaction. I visited the doctor after two weeks and they ordered tests which take a week and a half. The final test came back as inconclusive. Since my symptoms continued I requested a prescription for Bactrim which worked immediately. My symptoms are gone after 3 days. The press coverage helped me identify the issue but I had to be very proactive with pursuing a solution. There must be lots of causes for diarrhea which make it complicated to resolve.”

But not everyone can tolerate this medication. More on that shortly.

The Cyclospora Outbreak Has Become Enormous

The latest CDC numbers from August 11, 2026 are breathtaking. Explosive diarrhea cases attributed to Cyclospora have now been detected in 47 states.

As of August 10, the CDC had received reports of “13,895 laboratory-confirmed cases of cyclosporiasis” since May 1. Another 10,455 reports require additional investigation.

Add those categories together and public-health officials are dealing with more than 24,000 reported or suspected cases. We bet that a lot of people have gone undiagnosed and untreated.

At least 740 people have been hospitalized. Two people have died.

For comparison, the CDC recorded just 1,180 domestically acquired cases during the comparable 2025 surveillance season. In other words, 2026 isn’t just another bad year for Cyclospora. It is extraordinary.

And the CDC warns that the numbers are still likely to rise because there can be about a six-week delay between the onset of illness and a case finally appearing in the federal statistics. That means today’s numbers are partly a rearview-mirror picture of what was happening weeks ago.

The Cyclospora Outbreak Was Bigger Than Taco Bell

Early in the investigation, Taco Bell received a lot of attention. Thousands of people who became ill had eaten at the chain, and investigators found a striking association with shredded iceberg lettuce. Traceback records eventually converged on iceberg lettuce from central Mexico supplied by Taylor Farms de Mexico.

The recalled lettuce wasn’t confined to Taco Bell, though. It went to restaurants and food-service operations across numerous states, and Marketside iceberg salad and shredded lettuce products were sold at selected Walmart stores. Taylor Farms recalled all iceberg lettuce sourced from central Mexico on July 17. The affected retail products had use-by dates that have now passed, and the CDC says they should no longer be available in stores or restaurants.

That is reassuring. But it does not explain every case of cyclosporiasis in America.

The Cyclospora Outbreak in NC Raises More Questions

This is where the story gets especially interesting for us. North Carolina has reported 906 cases as of August 11. “Only” 31 people had been hospitalized. Wake County has had an astonishing 508 cases.

For perspective, the entire state of North Carolina has averaged roughly 150 cyclosporiasis cases per year over the last decade.

A crucial detail:

The North Carolina Department of Health and Human Services says the increase in cases here does not appear to be associated with the outbreak involving Taco Bell. State investigators have not yet identified the source.

They have, however, noticed something intriguing. North Carolina patients have reported eating parsley and cilantro more frequently than would normally be expected based on population food surveys. That does not prove either herb is contaminated. But it certainly illustrates why it would be a mistake to announce that the mystery has been solved simply because investigators traced one enormous outbreak to iceberg lettuce.

Apparently, Cyclospora still has a lot of secrets. After tens of thousands of illnesses, we think Americans are entitled to some answers.

If It Isn’t All Lettuce, What Is Making People Sick?

There is an even bigger unanswered question. The CDC has now counted 13,895 laboratory-confirmed cases of domestically acquired cyclosporiasis since May 1. But only 6,358 illnesses have so far been connected to the enormous outbreak involving iceberg lettuce from central Mexico.

Do the math. That leaves roughly 7,500 confirmed cases that are not currently explained by the iceberg-lettuce outbreak. And CDC says it is aware of another 10,455 cases that still require additional investigation or do not yet meet its laboratory-confirmation criteria.

So what made all those other people sick? The unsatisfying answer is, we don’t know! The CDC acknowledges that it is investigating multiple clusters of Cyclospora illnesses from other sources that are unrelated to the iceberg-lettuce outbreak. That leaves consumers and healthcare professionals confused.

This week FDA Commissioner Kyle Diamantas told CNBC that:

“We have the safest food supply in the world, period, full stop. Americans should feel confident in eating fresh produce including leafy greens at this point. FDA remains confident that all iceberg lettuce related to the Cyclospora outbreak have been effectively removed from the market…”

During this interview, Mr. Diamantas (the head of the FDA is a lawyer, not a physician) emphasized how well the FDA has tracked cyclosporiasis in the Midwest. But this disease has now been identified in 47 states and North Carolina, our home state, has been hit hard. The possibility exists that foods other than lettuce may be involved in this outbreak.

We are months into a nationwide surge involving tens of thousands of confirmed, probable or still-unclassified cases, and we still cannot tell Americans what foods account for a substantial portion of them. The iceberg lettuce mystery may have been partly solved. The Cyclospora mystery has not.

Our Friends Never Ate at Taco Bell

Our friends’ experience brought home something statistics cannot convey. Imagine enjoying a vacation at the beach, eating what you consider a healthy salad and then developing relentless watery diarrhea. Cyclospora can be especially nasty because the illness may seem to improve and then come roaring back.

The CDC describes frequent and sometimes explosive bowel movements. People may also experience stomach cramps, bloating, nausea, loss of appetite, weight loss and profound fatigue. That description is no longer theoretical for us. We have watched someone we care about struggle with this infection. Our friend has been suffering from fatigue for weeks.

And then we discovered that she faces another problem.

The Cyclospora Outbreak Exposes a Treatment Achilles’ Heel

There is a very effective treatment for cyclosporiasis:

Trimethoprim-sulfamethoxazole (TMP-SMX), better known by the brand names Bactrim and Septra. Unfortunately, our friend cannot take it. She really is allergic to sulfa antibiotics.

As described previously, that puts her in an unpleasant therapeutic corner because the CDC states that no highly effective alternative treatment has been identified for people who cannot tolerate TMP-SMX. Options can include supportive care while the infection runs its course, consideration of drugs backed by much weaker evidence or, for carefully selected patients, evaluation by an allergy specialist to determine whether TMP-SMX desensitization might be possible.

Desensitization is not appropriate for everyone, particularly someone with a history of certain severe or life-threatening drug reactions. Research published in the journal Infection Control and Hospital Epidemiology (Feb. 2, 2026) highlighted exactly this dilemma. It also raised an important point: some people carry a “sulfa allergy” label even though the original reaction may not have represented a true allergy.

That does not mean anyone should simply try Bactrim again. Sulfonamide antibiotics can cause serious reactions. A clinician or allergy specialist needs to examine what actually happened, how long ago it occurred and whether the person’s history makes testing or a supervised challenge appropriate.

Our friend’s situation is unfortunately simpler. She knows she cannot tolerate the drug. For someone with weeks of recurring diarrhea and fatigue, being unable to take the treatment of choice is not a trivial inconvenience.

Why Can’t We Stop This Before People Get Sick?

That brings us back to the question we asked three weeks ago:

How did so many contaminated vegetables get so far through the food system before anyone figured out what was happening?

The FDA Commissioner can reassure us that we have the safest food supply in the world, but there is still a lot we don’t know about the Cyclospora outbreak. And then there is the more recent Salmonella problem with jalapeño peppers. The contaminated peppers have triggered recalls involving prepared products sold through retailers including Hannaford, Kroger, Stop & Shop, Target, Trader Joe’s, Walmart and Whole Foods. Some Taylor Fresh Foods products containing the recalled jalapeños are among those being pulled from the market.

That does not mean the company contaminated the peppers. Its products were downstream recipients of jalapeños recalled by a supplier. This is precisely why modern food traceability matters. When an ingredient is contaminated, investigators need to know exactly where it came from, where it went and what products contain it.

CBS News reported this week that the FDA had not inspected the Taylor Farms de Mexico facility believed to be associated with the iceberg-lettuce outbreak for seven years. Its previous inspection was in 2019. The inspection before that occurred six years earlier, following another cyclosporiasis outbreak in 2013. Investigators at that time found that the facility was recycling wash water used for salad mix, although they could not establish precisely how the 2013 contamination occurred.

This is not merely about one farm or one company. The Government Accountability Office has repeatedly warned about weaknesses in FDA food inspections. From fiscal years 2018 through 2023, the FDA conducted an average of only 917 foreign food-facility inspections each year. The GAO says the agency has not met congressionally mandated inspection targets since 2018 and has struggled with shortages of inspectors. CBS reports that fewer than 1,000 foreign food-safety inspections were performed in 2025.

To be fair, an FDA inspection is not a magic protection shield. Food companies have the primary responsibility for making sure their products are safe every day. The absence of recent inspections does not mean that more frequent inspections would necessarily have prevented this particular outbreak. But inspections are supposed to be one of our early-warning systems. When tens of thousands of Americans become sick before the system catches up, it is reasonable to ask whether that warning system is working as well as it should.

One More Question for the FDA

Why did it take so long to realize how enormous this outbreak had become?

The CDC says there can be a six-week lag between the time someone becomes sick and the time that case is incorporated into federal outbreak statistics. Think about what that means during a fast-moving foodborne outbreak.

People eat contaminated food. About a week later they develop symptoms. Some wait before seeking medical care. Their doctors may not initially order a test for Cyclospora. Stool samples have to be collected and analyzed. Results must make their way through local and state health departments. Patients then need to remember what they ate days or weeks earlier. Investigators have to search those interviews for patterns and trace suspect ingredients backward through an extraordinarily complicated food-distribution system.

Eventually the CDC sees the national picture. But by then, thousands of people may already have eaten the contaminated food. In my opinion, that is not much of an early-warning system. The CDC acknowledges that the molecular tools for identifying related Cyclospora infections are still being developed and validated.

By August 10, CDC knew of 13,895 laboratory-confirmed domestic cases, 740 hospitalizations and two deaths. It was also sorting through at least 10,455 additional cases. Yet one enormous iceberg-lettuce outbreak explains fewer than half of those confirmed illnesses. For thousands of Americans, we still cannot answer the most basic questions:

What did they eat? Where did it come from? Was it parsley? Cilantro? Another vegetable? Several different foods? And are there contaminated products or growing regions that investigators still haven’t identified?

That concerns us. The CDC describes surveillance as a system designed to help officials “swiftly” identify and investigate outbreaks. But a surveillance system that can lag illness by six weeks is inevitably looking in the rearview mirror. Consumers deserve more than excellent detective work after thousands of people become sick. We need a food-safety system capable of detecting trouble much earlier. Because when more than 24,000 confirmed or suspected illnesses are on the radar and authorities still cannot explain a substantial proportion of them, saying that the investigation is “ongoing” begins to feel less reassuring with every passing week.

What Should You Do About the Cyclospora Outbreak?

We are not suggesting that everyone stop eating salad. The iceberg lettuce recalled in July should now be out of the food supply. But this summer’s outbreak offers several lessons.

If you develop persistent or recurring watery diarrhea, particularly after eating fresh produce, don’t just assume you caught a “stomach bug.” Tell your healthcare provider what you ate during the previous couple of weeks and ask whether testing for Cyclospora is appropriate. Routine stool testing may not always look specifically for this parasite.

Drink enough fluids and electrolytes to prevent dehydration. And if your medical record says you are allergic to sulfa drugs, make sure you know why. If you genuinely experienced a serious reaction, that information is crucial. If the label appeared decades ago and no one can remember what happened, an allergy specialist may be able to determine whether it is accurate.

Do not experiment with Bactrim or Septra on your own!

Final Words from The People’s Pharmacy

A month ago, Cyclospora was an intriguing and infuriating public-health mystery. Today it feels very different. Two people we have loved for more than half a century became part of the statistics. They didn’t eat at Taco Bell. They don’t know exactly which food made them sick. One is still struggling because the best treatment for cyclosporiasis is a medicine she cannot take.

Multiply experiences like theirs by thousands and the numbers take on a different meaning.

More than 24,000 confirmed or additional cases are now on the CDC’s radar. Hundreds of people have been hospitalized. Two have died. One important piece of the puzzle has been traced to iceberg lettuce from central Mexico. Other pieces remain scattered on the table.

Perhaps the most important lesson from this Cyclospora outbreak is one we keep relearning the hard way:

Food safety should not begin after thousands of people develop diarrhea. We ought to know where our food came from before people get sick. And if your idea of “healthy eating” includes a big fresh salad, as ours certainly does, you deserve a food-safety system capable of telling you whether the ingredients really are safe. We remain devoted fans of our local farmers’ market.

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