The Cyclospora Mystery: How Human Poop Got on So Much Lettuce

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So look, I had their look. Diary of boots, clothes of Diary of Boole, we can't eat like, come here, I'll go at it. I was sick of it in the day and dollar on the side of the river, man, I ain't lying to you, but no leg. I don't know where I got it from. I think it was lettuce. I'm not 100% sure. Where I got it?

I would get nauseous here and there. I had a such like low appetite, and I'm a brother that loves to eat.

“On Wednesday, US health officials linked six more states to what's now the largest outbreak of cyclospora in American history.”

An outbreak that is contributed to at least two deaths,

second thousands of people, and has left the rest of us increasingly scared of salad.

When I tell you, I went 32 times in one day, I'm not patriomatic. I'm not making that number up. I'm being so truthful. I feel like every day, the FDA got a whole new recall, like they can barely keep up with what's getting recalled today. Two public health reporters who have covered the parasite. Christina Jewett and Caroline Hopkins, Legaspi.

On what we've learned about where it comes from, how it spreads so quickly, and why our food safety system seems so powerless to stop it. Do you know something? If you know something or you know somebody that knows somebody that knows something, let me know. Is it okay to eat the lettuce? Because I really, I really, I really want to eat lettuce.

I need my greens. Please. Thank you.

It's Thursday, August 6th. So we're just going to test both of your mics well fast, and tell us what you have for breakfast. That's how we do this. Pistachium often, no iceberg, not on the side, not on the muffin. No iceberg. Okay.

Yep. No iceberg lettuce and my yogurt and granola either. Okay. And I, as usual, had eggs and sausage. Okay. So Christina, Caroline, thank you for coming to this studio for what I admit will be a somewhat stomach-churning at times conversation. Glad to be here. Yeah. Thank you for having me. So I just want to begin with the observation that it's genuinely surprising at least to me that we are still living with and talking about this outbreak because it began in June, late June, but June.

And it's still somehow expanding. How can that be? Yeah. This really is expanding. So in a typical year, you would see about 3,000 cases of cyclists for a done, but right now we're in August, and federal officials are still looking at 10,000 confirmed, 12,000 possible. So you're looking at potentially at 22,000 cases.

Which is from your math seven times a normal year's worth of outbreak. Yeah. But you can see why this would pile up. For one, you do your typical washing procedure at your kitchen sink. That's not going to kill the cyclist for a.

“I mean, you can't kill it by cooking it, but I mean, who's cooking their iceberg lettuce, right?”

And it's been on the shelf for a while. The lettuce that was potentially infected, that was good all the way out through August 3rd. So you're just now starting to see that get a little brown and mushy in the back of the fridge. So for the cases to continue popping up is really not that surprising. Fascinating.

And it can take weeks after you consume something contaminated with cyclist for a to start feeling symptoms. Scientists call this long incubation period. So you might not even start to have the diarrhea until a couple weeks after eating the thing. And then after that, you might not go to the doctor to get your stool sampled and tested for cyclist for another few weeks. So this can be really a long process from when somebody eats the contaminated thing to when they get diagnosed.

And then there's even more time between that diagnosis and when a public health official would officially report the case. Got it. So there's a long tail to this and based on what you just said, Christina, people may just be getting around to eating the lettuce that makes them sick.

Yeah, this could last.

“Well, the reason you're both here is because you've somewhat unwillingly become authorities on this outbreak.”

So let's talk about how the outbreak has played out.

What we've learned about its origins and ultimately what we've learned about our food safety system and the process.

So where does this outbreak begin? So this begins across the country but mostly in the Midwest back in the beginning of the summer. It's related to report severe diarrhea and stool sample testing show that it was this parasite cyclist for a and more and more cases began to mount, which got the attention of state public health agencies followed by the CDC. And on July 14th, the CDC officially announced it's opening an investigation into this outbreak.

And this is the moment where all of us are like cyclohan, like tell us about this parasite. This is a parasite that spreads through food or water that's just, I'll just say it's contaminated by human feces.

“So that's pretty much the only way that it spreads, at least that scientists are aware of.”

So somewhere somehow there's a food source that has human fecal matter on it. Somebody eats it and this parasite it enters the body and these little pods called osis. And they're kind of like eggs, but they make their way down into the intestines where they burrow into the wall of the intestine. And the parasite emerges from these osis and starts to infect the cells that line your intestine. So this whole process can take anywhere from a few days to two weeks.

As this parasite comes out of these little osis and begins to reproduce first, you know, just asexual reproduction.

Then it's reproducing sexually so with each other and just exponentially there's more and more and more of these. I totally neglected the trigger warning that was required to have this conversation because now we're talking about sexual reproduction of a parasite. Okay, but I need you to keep going sadly. Yes. So at that point when these cycles for a parasite have infected your intestinal walls to the degree that you can't absorb the nutrients and the fluids that you're eating and drinking. That's when you start to see this really, really bad diarrhea that people describe as explosive debilitating.

It can't go to work. They can't go to birthday parties. They're just sitting on their toilet and they're miserable. It's a very nasty parasite. And as you said, if you've somehow gotten cyclospor, you have somehow ingested remnants of human fecal matter. So I'm guessing it's at this moment that the race begins to figure out how on earth that fecal matter got on food. So Christina, maybe pick up the story from there. Yeah, so this is where epidemiology comes in. You have state public health officials, local officials. They want to do a 90 minute interview with you.

They want to know everything you ate weeks ago, especially fresh raw produce that maybe hasn't been washed. They want your loyalty, you know, number for the grocery stores where you shop routinely. They're going through the safe way shopping records. Yeah, and they want to know what's on your credit card and your debit card. If you ate at Taco Bell, if you ate it subway where you ate. And they do these interviews with dozens and dozens of people and they're looking for commonalities.

They want to create a big venn diagram and see, you know, exactly what pops out.

And where does that venn diagram ultimately point?

So these interviews are tricky because few people can remember exactly what they ate for, you know, weeks, weeks. And if they do remember, they might remember I had a taco, not I had a taco with shredded iceberg lettuce and cilantro and peppers. But with enough of these interviews, you can sort of start to tease that out.

“And that's how investigators landed on shredded iceberg lettuce from tailor farms, grown in Mexico, sold at Taco Bell.”

Okay, I think we should focus on tailor farms because it seems they're the distributor of this food, but tell us everything you know about tailor farms. tailor farms is a huge company, very, very big and fresh produce. They have contract growers all around the country outside the country in Mexico as well. And essentially, they ship bags of shredded lettuce to middlemen and middlemen of middlemen and it goes out to cafeteria's mom and pop restaurants, chain restaurants all the way through the food chain.

One way or another, you've probably eaten lettuce that tailor farms touched even if you didn't know it. Absolutely yes. And those bags of salad mixes that you see on the grocery store shelves are, you know, washed, pre-cut lettuce.

So the way to think of tailor farms is that they're getting a lot of lettuce from a lot of farms. And the authorities are suspicious of it sounds like Mexico as the source of this problem.

“What do they think? What do they suspect may have happened in Mexico?”

So we don't know what happened on this farmer farms in Mexico.

And we honestly might never know because a lot of these outbreak cases end up as cold cases are never solved.

But we can look to some of the cases that have been solved in the past as examples and sort of tease some hints out of those that might have happened. And a lot of that points back to agricultural water. So the water that's used to irrigate the plants to wash the lettuce to spray it with pesticides. Any of those uses of water you're distributing potentially a contaminated water source over all of the crops. So somehow that water has to be contaminated.

Exactly. So that's where you go back to nearby bathroom facilities, latrines, sewage overflow. Any of these explanations for how poop water essentially can get onto these plants. Yeah, yuck. Yuck is right. For example, in the late 90s there were a series of outbreaks that they were able to trace back to some farms in Guatemala that grew raspberries.

And in those cases, the leading theory was that this water source that they had used to mix with a powder pesticide to make it a liquid solution.

“They could spray all over the raspberries.”

That water source had been contaminated. And similarly in 2020, they traced an outbreak that affected iceberg lettuce and cabbage and carrots back to some farms in Florida that had been contaminated with water from the canal. Interesting. Also means that when you're in the grocery store looking at pre-washed bags of lettuce, they're probably adding even greater risk than the whole heads of lettuce. And the reason for that is that the agricultural water that could have been contaminated is being used to wash this lettuce.

So, you know, you're seeing triple wash, you might think that's safer, but in reality, it's kind of ironic that bag of pre-washed lettuce might have been exposed to the contaminated poop water three times over. Right, not what you think of when you think of wash three times. Exactly. Exposed three times. Right.

And a lot of people at this point say, well, why can't we just treat the water with chlorine or with, you know, whatever standard. But cyclospora is a really tricky bug because this parasite is really resilient and those standard techniques don't kill. Wow, chlorine does not kill cyclospora. Right. Does that mean that people who have this parasite are putting it into our sewage system and it's potentially spreading that way or no?

“We don't have any reason to believe that that's what's happening.”

I mean, cyclospora does not pass from person to person. Got it. Okay. So, Christina, at a certain point after epidemiologists have figured out, this is cyclospora, and they have determined that the leading suspect is Mexican farms, that are used by Taylor Farms.

That's when a recall comes in. Can you just describe that recall and how it worked or didn't work? Yeah, essentially the FDA leans on the company to do a voluntary recall. And we saw that in mid July with Taylor Farms. But what we saw come out from Taylor Farms was a little bit confusing.

So basically the supply chain of a company like Taylor Farms is sort of considered a corporate secret.

I mean, it's considered a trade secret because it's the company's sort of relationships with vendors and suppliers. And that's something the company wants to protect. So the company put out information about what was being recalled. You see four and five pound bags of shredded lettuce. You see some 16 ounce bags.

And then there were a whole lot of codes codes. Yeah. But what were these codes? P.K. S.Y.

M.A.R.K. J.B. C.V. So my colleague Julie Cresswell in the business department, all of us really just went to try to do some detective work and figure out what are these codes.

I mean, my first step was saying, "Hey Taylor Farms, what are these codes mean?"

Radio silence. No answer. Yeah. They don't want to say for proprietary reasons who's getting their lettuce. Right.

Even though this is the moment when presumably the public very much wants to understand that. And they don't even have to tell the FDA. And they sit on top of quite a food chain. I mean, we did find out that some of the lettuce went to bag salad sold at Walmart under the market side. We found out that some went through Cisco, which is a pretty sophisticated kind of a middleman company that supplies.

College cafeteria's corporations. Yeah. Lots of different sites.

And she said, "Yeah.

“This is something food safety advocates have been talking about for years saying FDA needs to have the authority to tell companies that you need to.”

And no one certain terms disclose your supply chain and the event of a recall like this.

So everybody knows what's what? Because if you're a mom and pop restaurant and you're looking at this recall, you might be throwing your hands up. And not even know if your regional supplier has been affected by this. So because of the way Taylor Farms communicates this recall through literally coded language, you're saying a bunch of people probably wouldn't necessarily have understood that they were subject to a recall.

And they could be sitting on and serving these bags of potentially contaminated lettuce that Taylor Farms is recalling, but these folks wouldn't necessarily even know to take them off their shelves, not surface lettuce. That's right. And that's how you potentially end up with a very long tail of this outbreak. And that's how you end up with people standing in the produce section of their grocery store saying, "I'm not buying any lettuce."

Hmm.

My instinct is to question how something like iceberg lettuce could ever be a trade secret for anybody,

because it is iceberg lettuce. But also that an exception wouldn't be made in the middle of a very dangerous foodborne illness outbreak to put aside worries about trade secrets and just tell everybody who has this lettuce. Yeah, you would hope so you would think so. I mean, in this case a very high profile outbreak that has turned deadly,

there was no high-powered US government pressure to make them disclose that. You know, I'm looking at this recall page right now, and it's still a big list of codes. All these weeks later. All these weeks later.

“Well, Christian, what you're describing, I think begins to hint at how much our entire food safety system ends up making it harder to get to the bottom of this outbreak.”

And we are going to talk about that in a lot more detail. Right after the break. We'll do it back. The New York Times app unlocked. Everyone knows the times is behind a paywall.

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A month to go behind the paywall. To see what time subscribers get every single day. All the investigations, the reviews, the recipes, the deeply reported fact-based journalism. If you don't already subscribe to the New York Times, download the Times app today and get free access for 30 days. So, Christina and Carlin, we're going to talk now about the government systems in place that in theory might have caught this outbreak, but clearly didn't.

And, Christina, I want to start with you and the farms in Mexico where it's suspected this all started.

“Who's responsible for inspecting the conditions there?”

So, it's the Food and Drug Administration. They inspect the food processing facilities and they have inspectors who go out all around the world. And when you're talking about the food processing facility that this has been traced back to, it was Taylor Farms plant in Northeast Mexico, the FDA actually has not set foot there since 2019. Wow.

U.S. inspectors haven't been to that facility in seven years. That's right. And, you know, that's not that surprising. One out. 300,000 is the number of FDA registered international food facilities that the U.S. government has an eye on.

But they don't have that many inspectors. How many do they have? There's 450, and that's for the United States and the world. Wow. Roughly 450.

Yeah, that math doesn't really add up. It really doesn't. So, you're seeing facilities not getting visited for years and years. The number of inspectors you're describing and the number of facilities that they're responsible for, suggest that the U.S. government must understand that it's not going to catch every year.

So, what's the logic there? I mean, that's really sort of a reflection of the funding that FDA's gotten over the years from Congress. And while that funding sort of stagnated, the FDA's passed rules for food processors to follow.

Basically, like, you know what you make. You know what the risks are.

So, test your products. Be very careful and control your risks. That's interesting. Caroline, this reminds me of the U.S. government's reliance on several industries to kind of self-police. And we've covered, for instance, the airline industry on the show a lot. The thinking is that airlines are deeply invested in the safety of their passengers. If there's an airline crash, it's terrible for the reputation of an airline. Obviously, it's terrible for the people who died.

Everyone's incentives are aligned to keep airline safety really strong.

“Is that basically the argument here when it comes to food suppliers?”

Every farmer and farm in Mexico wants food to be safe, too. Right. And these farms want buyers like Taylor Farms to want to buy their lettuce. And then, Taylor Farms and similar companies don't want people to get sick from their produce because that would injure their business. Right. So, in that case, incentives are aligned. But do we know if any or all or some of these farms are testing for Cycle Spora?

We really don't know right at this moment. I mean, the FDA is going to be investigating this. And they will issue reports that are made public. But on a farm to farm level, we really, at this time, have no idea. It is important to know that it's really hard to test for Cycle Spora in the environment.

“Why? So, it was described to me as a needle in the haystack scenario.”

So, you're looking for something that might not be evenly distributed across an entire batch of lettuce. So, you take a sample. That sample might not have these microscopic osis on it. The same goes for a water source. It's sort of like testing the ocean, right? If you're looking for a certain fish, it's not going to be in that necessarily in that little bit that you're testing. Right. I'm going to guess there are listeners out there thinking themselves, you know. We can test for cancer in the blood. We can send men to the moon.

We can find poop in the water on a farm in Mexico. This is really where science comes into play. I mean, I've covered a number of outbreaks. And sometimes there are sort of like indicator species, or a certain level of fecal contamination, maybe in the water that should trigger deeper testing. I mean, you have a system in this country of food safety under the umbrella of the FDA and CDC. But as much as we care about not having poop-tainted lettuce, we really don't heavily support these areas.

As taxpayers. Right. Interesting. Basically, not that much energy or money is being put into this testing processing.

That's right. Well, I wonder if it's possible that cyclists for a isn't seen as enough of a risk to put that much energy or money into. And Christina, you said these companies are told by the US government know your risks and take care of them, Caroline is a possible that. So far, cyclist, that's seen as one of those. Yeah. I mean, up until now, it's just really not been that big of a risk. Right. Which means that could change. We just don't know yet. Okay. So I want to turn to the larger US public health system and how it's handled this outbreak so far. And how it's talked about it.

I'm curious if you guys would agree with me on this, but it doesn't feel like US health officials have talked and communicated all that much about this outbreak.

“I can't recall a major news conference from anywhere in Washington about it. And should I have expected one?”

Yeah. I mean, I think we've heard Robert F. Kennedy Jr. you know, it event on a different topic say basically we have this under control.

Well, does that feel accurate? Does it feel accurate? Absolutely not. Yeah. And state public health officials are saying absolutely not. Hmm. So why would the Secretary of Health claim something's under control that's not? And overall, just not seem like I communicate about it. Yeah. Well, he's part of an administration that's really heavily focused on deregulation.

So to make this a centerpiece issue, you probably be looking at writing regulations. Yeah. Which is perhaps not so appealing to Robert F. Kennedy Jr. right now. And what ends up happening is a lot of the burden for doing these investigations for doing this complicated traceback interviewing all of these people. This is falling on state and local public health departments. And that's happening in a time when they are really underfunded and they do not have the staff or capacity to do this type of work.

I mean, in 2026 state health departments said they received just 40% of what they asked for to monitor, detect and respond to food burn illness.

Right. That's what they asked for from the CDC that funds most of their work.

“And what I found in my reporting is that the Trump administration is working on a plan to actually hand off about 90% of all the food facility and farm inspections that go on in the United States over from the FDA to the States.”

Wow. Yeah. So if the funding situation remains unchanged, that could be a really interesting transition to watch. So you're saying at the precise moment that states are already saying they're insufficiently funded to do this kind of stuff.

The Trump administration for cost cutting purposes is planning to shift more and more of this work to the States away from the federal system.

That's exactly right. Even to states that don't even really have a food safety program. I mean, telling you if I'm wrong, all of what you're describing seems to point to a food system that has a lot of risk baked into it. A system where we expect food from all over the world to show up at our grocery store, providing us with year-round lettuce, strawberries, blueberries, whatever.

“And isn't that just a system as we now have it very lightly regulated by the government where outbreaks should be expected, or should we see what's happened here as a failure of that system?”

I mean, I think they are expected. I think it's too be expected, but when you have a parasite like this, and you have the gross out factor on 11, I mean, I really do think that gets people's attention. And it creates a moment where we can have these conversations and we should at a high level be having these conversations. About whether this is us working. Right. Whether it's funded, whether it's supported, whether it's as important, really as it should be, given it's, you know, central place at the kitchen table with all of us and our families.

Yeah. And we just heard on Monday that two people have officially died from cyclist borough, which up until this point, they're hadn't been any deaths. I mean, the state of Michigan where these people died did say that they had severe underlying health conditions. Even so, I mean, this has come to a point where people are really paying attention. This is dangerous.

“When do you think, given all the factors you both described at the beginning of this conversation, this outbreak is going to end?”

Food safety epidemiologists, everybody I've talked to you said there has a dent to predict the future. But there have been some early signals that at least in Michigan, which is the epicenter of this outbreak, the rate at which new cases are increasing seems to be slowing a bit. But even after this contaminated food source is no longer in our food system, we still might see the cases go up because it takes so long to get sick. In the meantime, very quickly, how are you both navigating? Let us right now. News you can use.

I'm sticking with dark leafy greens. The kale's the spinach. I haven't heard anything about any links to those, so I've been kind of a spinach gal for the last month. I'm with you there. I've also been on a bit of a roasted vegetable kick. I'm not going to lie. Nothing like killing everything in the pot with a little bit of heat. Right. This is a strange moment for salad. Well, Caroline and Christina, thank you very much. Appreciate it. Thank you. Thank you for having me.

We'll be right back.

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