By Will Atwater
Takeaways:
- A record Cyclospora outbreak tied to lettuce from Mexico sickened thousands across multiple states, but N.C. officials say the state’s cases don’t appear to be linked.
- The parasite spreads through fecal contamination of water and soil, is hard to detect, and is resistant to killing.
- Experts say multiple demands on the food system leave consumers vulnerable.
The largest cyclosporiasis outbreak on record in the U.S. this past summer sickened 12,883 people in 21 states, including North Carolina, before the Centers for Disease Control and Prevention declared it over on Sept. 11.
The outbreak, which led to 570 hospitalizations and two deaths, was linked to iceberg lettuce from Taylor Farms de Mexico. The company recalled all iceberg lettuce sourced from central Mexico on July 17. The Food and Drug Administration’s investigation is ongoing.
In North Carolina, the picture is more complicated. The state Department of Health and Human Services has reported 955 cyclosporiasis cases and 32 hospitalizations since May, more than half in Wake County alone. That’s compared with the roughly 150 cases a year the state averaged over the past decade. NCDHHS says the increase does not appear tied to the national lettuce outbreak.
Recent patients reported eating parsley and cilantro more often than expected, but no source has been found.
Tracing Cyclospora to its source is almost always challenging, in part because the parasite is hard to detect.
“We don’t have good environmental methods to be able to go out and look for this pathogen in the environment,” said Chip Simmons, a fresh food safety expert with N. C. State Extension.
Simmons spoke during a presentation on Cyclospora at the North Carolina Food Safety and Defense Conference, which was Sept. 1-2 at N.C. State University’s McKimmon Center. He walked through what could have led to the outbreak. The possibilities point to vulnerabilities in a food system built to deliver lettuce, strawberries and other fresh warm-weather produce to grocery shelves year-round.
Meeting that demand depends on a sprawling international network of growers, packers and distributors, many far from consumers. U.S. agricultural imports totaled $212 billion in 2025, and Mexico has been its largest importer in recent years. The country supplies roughly one-third of U.S. horticultural imports, including fruits and vegetables, according to the U.S. Department of Agriculture. The lettuce behind this summer’s outbreak came from central Mexico, according to the FDA, and was served at Taco Bell restaurants and sold at Walmart.
Each step along the way adds another chance for contamination. The system also depends on the people who harvest the crops and the inspectors who check them. That raises questions about working conditions in the fields, whether too few federal inspectors have the resources to keep up, and how a warming climate may add to the risk.
Exposure pathways
In places where Cyclospora is endemic, or commonly found, one way the parasite can reach produce is through water contaminated with human feces that is then used to irrigate or wash crops, Simmons said.
Infected people, including those without symptoms, shed the parasite in their feces. Without adequate sanitation it can contaminate water, soil and food, according to the FDA. Unlike many other foodborne pathogens, the parasite must spend one to two weeks in the environment before it can make someone sick, so it is unlikely to spread directly from person to person, the agency says.
“Then things are just made even worse in the post-harvest environment,” Simmons said, “because one of the characteristics of [Cyclospora] is that it’s not well controlled by sanitizers.”
Simmons said that in bagged-salad processing, a small amount of contamination can spread to more product during chopping and washing. The wash-water sanitizers that control many other pathogens may not work against Cyclospora, he said, so the parasite can persist on processing equipment and spread during handling. The FDA notes that the parasite is resistant to standard chlorine-based sanitizers.
Simmons was describing how contamination can occur in general. The FDA has not concluded how the lettuce in this summer’s outbreak became contaminated.
Eric Deeble, a large animal veterinarian and former deputy under secretary at the U.S. Department of Agriculture who now leads Americans for the Common Good, an agriculture policy nonprofit, was blunter:“Cyclospora is interesting because it’s a single-cell organism that only infects humans. If you’ve got a problem with Cyclospora in your food system, you’ve got a problem with human [feces] in your food supply.”
Workers face quota pressures
Advocates say conditions for North Carolina farmworkers are getting harder. Last October, the federal government cut the minimum wage for H-2A guest workers in the state from $16.16 to $12.78 an hour and began letting employers deduct $1.69 an hour for housing, WFAE reported. In August, a federal judge ruled that the new wage method was unlawful but left it in place until Dec. 30, 2026, when the the Department of Labor must finalize new H2-A wage criteria.
Sweet potato harvesters earn 50 cents a bucket, a rate unchanged for more than 20 years, according to the September newsletter of El Futuro es Nuestro, a farmworker advocacy group. Workers must fill 22 buckets an hour or risk being fired, said Leticia Zavala, a staff organizer with the group.
Federal Occupation Safety and Health Administration regulations mandate that farms with 11 or more field workers provide a toilet and handwashing station for every 20 workers, within a quarter-mile walk. But when quotas are in place, advocates say, even a few minutes away from the row can cost workers pay and put their jobs at risk.
Federal rules require employers to top up pay when piece-rate earnings fall short of the hourly minimum, but workers who miss a production quota can still lose their jobs, according to the federal Labor Department. Since June 2025, the department has also suspended enforcement of 2024 protections that clarified when H-2A workers could be fired for cause.
Those pressures matter for food safety. Federal produce safety rules require farms to keep ill workers away from crops until they recover and tell workers to report when they’re sick. But the rules depend on workers being willing to speak up; advocates say low pay and strict quotas make that hard.
Weakening guardrails
Deeble said federal surveillance of foodborne illness has been weakened in recent years. Since July 2025, the CDC’s Foodborne Diseases Active Surveillance Network, known as FoodNet, has required its partner states to track only two pathogens, salmonella and Shiga toxin-producing E. coli, according to the agency. Tracking Cyclospora and five other pathogens once monitored is now optional. A CDC spokesman said the change would help the agency “steward resources effectively,” the Associated Press reported in 2025.
FoodNet “was way better in the past,” when it tracked eight pathogens, Deeble said. (FoodNet stopped tracking Cryptosporidium in 2017.)
The CDC says other surveillance systems also monitor those pathogens, including the National Notifiable Diseases Surveillance System, which covers Cyclospora. It also says FoodNet was not designed to detect outbreaks and that how it and its partners detect and investigate them has not changed.
FoodNet staff work with more than 700 clinical laboratories to identify infections, and the data help health officials measure how common foodborne illnesses are, track trends and link illnesses to specific foods, according to the CDC. The network covers about 16 percent of the U.S. population in 10 states, with California and New York participating through selected counties. North Carolina isn’t among those 10.
Surveillance is only one layer of protection. Congress enacted the FDA Food Safety Modernization Act in 2011 to shift the nation’s food safety system “from responding to foodborne illness to preventing it,” according to the FDA.
The law set hygiene standards for farmworkers, required importers to verify the safety of foreign suppliers, and set a goal of 19,200 FDA inspections of foreign food facilities each year. The agency averaged only 917 a year from 2018 to 2023, according to the Government Accountability Office. When FDA inspectors arrived at the suspect Taylor Farms site in Guanajuato in mid-August, it was their first visit since 2019, the AP reported.
A warming climate could add to the strain. Heavy rain and flooding are “key drivers of food contamination and foodborne disease,” according to the federal government’s Climate Resilience Toolkit. Researchers are still studying how climate affects Cyclospora specifically.
A question of convenience
Deeble said consumers can reduce their chances of being caught up in large outbreaks linked to national supply chains.
“The best thing that you can do to avoid getting caught up in large national recalls of lettuce is buy local and buy from somebody you know and trust,” he said.
Agriculture expert Scott Marlow said, by email, the difference comes down to scale.
“Imagine a lettuce plant that becomes contaminated in the field,” Marlow said. “If the farmer sells that lettuce at a farmers market, then they may get the person or family that buys that lettuce plant sick. Maybe in the box or in the wash water it contaminates a couple more, so you get, maybe, 20 people exposed.
“But if that same lettuce plant gets sold for bagged salad, it gets comingled with a very large amount of other lettuce.[…] Now that one plant has the opportunity to contaminate hundreds and thousands of bags of salad, and thousands of people can get sick.”
Local produce isn’t risk-free. The FDA found Cyclospora in domestically grown cilantro in 2019. The source of North Carolina’s surge this summer remains unknown, but the outbreak’s limited geographic spread suggests it likely originated locally.
For consumers, buying from nearby growers means shorter supply chains and a chance to ask farmers directly about their practices.
Deeble also said consumers can push for policy policy changes, such as increasing funding for FoodNet so it can track more diseases. But, he said, the larger challenge is the demand for convenience.
“Is an informed consumer going to make choices that move the market?” he said. “Do you think enough people are gonna say, ‘Well, I don’t want a strawberry in February because I don’t know the greenhouse gas impact, the food safety concerns, the concerns with the health and safety of farmworkers in the global South?’”
Deeble said once shoppers expect fresh produce year-round, that expectation is hard to reverse.
“I think once that genie comes out of the bottle, it never really goes back in.”
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