Here’s why we’ve been seeing so much food-borne illness

This story was originally published by Vox and is reproduced here as part of the Climate Desk collaboration.

Summer is supposed to be the best time for fresh produce. Corn on the cob at the cookout. Berries plucked right from the vine. Salads on the cafe patio while you take an extra long lunch break because the weather and the food is that good.

But this year, summer’s harvest brought something much different than the flavorful dishes we’ve come to expect. Since May, the United States has seen more than 17,000 lab-confirmed cyclosporiasis cases. Before this summer’s massive outbreak, the country had never recorded more than a few hundred infections in a single year from this parasite, which can cause watery and at times explosive diarrhea.

And that isn’t the only bug invading Americans’ digestive tracts.

One person died from a listeria infection traced to ricotta cheese. Close to 100 people came down with salmonella from recalled eggs, while more than 400 people have gotten sick in a separate salmonella outbreak involving jalapeños. Last week, the Food and Drug Administration issued its highest urgency warning for frozen blueberries believed to be contaminated with E coli.

And now several dozen people across 15 states have become ill after eating alfalfa sprouts in a new outbreak that involves salmonella and E coli. Four of them have been hospitalized.

It’s gotten so bad that one Washington Post columnist argued we should stop eating lettuce altogether. Experts have told me they were worried people might actually completely stop consuming vegetables—vital to any healthy diet—for fear of contracting cyclosporiasis and enduring a month of watery diarrhea. I personally avoided the bagged salad kits that provided me with many easy lunches on a workday.

While this spate of foodborne illness is especially bad, the worst may be yet to come.

It’s only natural to look for somebody to blame. Culpability has understandably fallen on the Trump administration and Robert F. Kennedy Jr., who helms the US Department of Health and Human Services—especially after his deep staffing cuts at the FDA and the Centers for Disease Control and Prevention, the two federal agencies most responsible for investigating and responding to disease outbreaks. Those cuts have slowed the response, and officials have struggled to communicate with the public clearly in a fast-moving crisis.

While our government officials are partly to blame, the problem is bigger than Trump and Kennedy, or even this one summer. While seasonal changes will always play a role—the warmer months, when people eat more fresh produce and consume more food that’s been sitting out at unsafe temperatures, typically have more foodborne illnesses—the underlying factors contributing to these outbreaks are becoming more potent. The food supply is more and more globalized. And the planet continues to warm, allowing these pathogens to spread to more and more farms all over the world, including in the US.

As the weather finally begins to cool down, I’ve been asking myself an uncomfortable question: What if diarrhea summer never really ends?

Our globalized food supply chain has a lot to do with our food safety—and that isn’t going to change any time soon. Americans expect access to any produce they want year-round, even produce that isn’t in-season locally, or that may not grow anywhere in the US at all. We source food from all over the world: Most cyclospora outbreaks originated with foods grown in other countries. This year’s crisis was eventually linked to iceberg lettuce from Mexico.

And as the New York Times recently documented, the sometimes international trip from the farm to the store for a bagged salad kit offers multiple moments for potential contamination, including tainted irrigation water, local wildlife excrement, and poor storage practices, making it possible for dangerous pathogens to take hold before a person even buys their groceries.

Warming temperatures around the world are also helping those bugs spread. Humidity is essential for salmonella and warmer summers will mean more humid-favorable conditions for the bacteria to grow. E coli likewise will thrive as temperatures rise. Cyclospora has historically been found in subtropical climates, so for a long time, infections from food grown inside the United States were unheard of. Not anymore.

“Climate change has allowed pathogens like cyclospora…to expand from the tropic, subtropic lines into areas more north and south of that tropic line,” said Joseph Eisenberg, a professor of epidemiology and global public health at the University of Michigan School of Public Health.

“With respect to the US, we’re starting to see new infectious diseases in southern Louisiana, Texas; that also increases the presence of cyclospora in food systems in other countries,” he said. “It suggests that, through climate change, we might potentially start seeing it be endemic in the United States at some point.”

And indeed, cyclospora was found in farms in Florida in 2020. This is a problem that is going to become worse, not better, given the expected trends in global warming in the decades to come.

“It wasn’t until about within the last 10 years we started to see cases from domestic origin,” Francisco Diez-Gonzalez, director of the Center for Food Safety at the University of Georgia, told me. “Before, there were predominantly cases due to international travel or importation of products because it used to be endemic in some tropical or warmer climates.”

“It’s clear that now,” he said, “it’s become established in the domestic environment.”

To make matters worse, at the same time conditions for foodborne illness are ripening, the US government has been sharply cutting its ability to monitor for and respond to these outbreaks.

At the beginning of the second Trump administration, as part of the widespread government staffing cuts, the FDA laid off 3,500 workers. Between the FDA and the US Department of Agriculture, which also oversees food safety, and several related agencies, more than 11,000 workers have been lost, a 22 percent cut, according to the Partnership for Public Service. And the CDC, which helps respond to outbreaks once they start, has lost about a quarter of its workforce from January 2025 to October 2025, according to Reuters; by this summer, CBS reported, the number of scientists tracking food parasites at the agency dropped from 11 to three. Meanwhile, the administration has been rushing to hire 2,200 people in the middle of the crisis.

“There have been a lot of federal cuts. There have been cuts around CDC surveillance, around state and local public health. You’ve lost people,” Dr. Anurag Malani, vice chief of staff at Trinity Health’s Ann Arbor, Michigan, campus, told me. “The ability to do what you need to do to keep citizens safe and to keep the public safe, we don’t have as many people doing that as we used to.

The federal government also shut down several national monitoring programs for foodborne illness in 2025—including for the cyclospora parasite specifically. The state and local agencies that surveil for and respond to food outbreaks have also faced staff cuts because they depend on the federal government for their funding.

“It’s hard when there is one larger entity kind of controlling all of that,” Dr. Kathleen Linder, the hospital epidemiologist at the Veterans Affairs hospital in Ann Arbor, told me in July. “Local health departments are having to do more on their own than they would have had to do in the past just because of decentralization at that level. It has been very hard to get updated information. The information has been lagging a little bit behind.”

Food safety is hard enough to tackle on its own. Part of the reason we experience regular outbreaks of cyclospora is that it can successfully infect people even when only very little of it is present, and because we can’t grow it in a lab to study it.

But the US has made things harder by cutting these important programs. Rebuilding the staff and capacity to do this work is not likely to happen under the Trump administration, and former FDA officials have described a “brain drain” for the food safety programs that won’t be easy to reverse in the next administration.

But something will have to be done if we’re ever to escape the food recall cycle. Despite the name, food has historically been neglected by the “Food and Drug” Administration, and better food safety could require serious restructuring and investment in these capabilities. And foodborne illnesses aren’t the only kind of infection that climate change will make more likely: The United States is also seeing the spread of mosquito-borne diseases like dengue. Responding to those new threats is going to require a rebuilt and potentially reimagined federal public health apparatus.

If there is any good news in the short term, it’s that there are a lot of great recipes for grilling your vegetables to eliminate any pathogens hiding in our side dishes at next summer’s cookouts. It sure seems like we’re going to need them.