As a massive Cyclospora outbreak sickens thousands of Americans, key federal research projects focused on the parasite are being cut or uprooted at a moment when scientists say more research is urgently needed.
According to the Centers for Disease Control and Prevention’s latest surveillance data, 17,180 laboratory-confirmed cases of cyclosporiasis acquired in the United States were reported between May 1 and August 24, 2026. That compares with 1,180 cases reported during roughly the same period in 2025. The CDC has also recorded 922 hospitalizations and two deaths among this season’s confirmed U.S. acquired cases.
At the same time, POLITICO reported that three projects accounting for nearly all of the Agriculture Department’s Cyclospora research are being affected by funding cuts and relocation plans. Two projects based at the Beltsville Agricultural Research Center in Maryland lost congressional funding, according to USDA, while another funded project is expected to move to Iowa. POLITICO reported that the scientists working on that project have declined to relocate.
The timing has alarmed researchers because Cyclospora remains unusually difficult to study.
“We know so little, and I think that that’s been very frustrating to consumers,” University of Delaware professor Kalmia Kniel told POLITICO. Discussing the potential loss of Beltsville’s capabilities, she added, “No one can work very fast. We don’t have the models, we don’t have these surrogates like we would want to have them, and we want to be able to do the research.”
USDA disputed the suggestion that its research has been interrupted. A department spokesperson told POLITICO, “None of the research has been disrupted, and research will continue without disruption.”
The spokesperson also said, “Congress did not appropriate funding for the two BARC research projects referenced in the FY2026 Agriculture Appropriations Act,” adding that USDA’s Agricultural Research Service “is working with research leaders to ensure an orderly transition of programs.”
Still, one USDA employee who had worked on affected research described a more restrictive situation.
“We’re basically not allowed to continue any research on that beyond trying to preserve the samples that we already have from previous outbreaks,” the employee told POLITICO. “We see this as an enormous opportunity, this current outbreak, to have really a lot of samples that could help us understand these outbreaks better.”
The concern is especially significant because Cyclospora cayetanensis is not a typical foodborne pathogen. According to the CDC’s medical overview of cyclosporiasis, Cyclospora is a microscopic parasite that infects the small intestine. People generally become infected after eating food or drinking water contaminated with human fecal matter containing the parasite.
Unlike illnesses that can spread quickly from one person directly to another, Cyclospora needs time outside the human body before becoming infectious. The CDC says the parasite generally requires at least one to two weeks in the environment after being shed in feces. That makes direct person-to-person transmission unlikely.
The Cyclospora outbreak has also highlighted how easily produce can become part of a large investigation. According to the Food and Drug Administration’s August 27 outbreak update, 11,458 illnesses in 20 states had been linked specifically to processed iceberg lettuce sourced from central Mexico and recalled by Taylor Farms de Mexico. That outbreak accounted for 495 hospitalizations and two deaths as of the update.
Taylor Farms de Mexico voluntarily removed iceberg lettuce sourced from central Mexico from the U.S. market in July. The FDA said recalled products included certain Marketside iceberg salad and shredded lettuce products sold at Walmart, while investigators also identified illnesses among people who reported exposure to processed lettuce served or purchased at other locations, including Taco Bell. The FDA says the recalled lettuce tied to this particular Cyclospora outbreak should no longer be on the market.
For people who become infected, watery and potentially frequent diarrhea is the most common symptom, according to the CDC. Other symptoms can include loss of appetite, weight loss, stomach cramping, bloating, gas, nausea, and fatigue. Some patients experience vomiting, body aches, headaches, or a low-grade fever.
Symptoms usually develop about one week after exposure, although the CDC says they can appear anywhere from two days to two weeks or longer afterward. Without treatment, illness may persist for days or more than a month, and symptoms can disappear before returning again. People with weakened immune systems can face more severe or prolonged illness.
Diagnosis can also complicate a Cyclospora outbreak investigation. The CDC says routine stool testing does not necessarily include Cyclospora, meaning health care providers may need to specifically request testing. In some cases, several stool samples collected on different days may be necessary to detect the parasite.
The CDC identifies trimethoprim-sulfamethoxazole as the standard treatment for cyclosporiasis and advises patients with symptoms to speak with a health care provider. Staying hydrated is especially important because prolonged diarrhea can lead to dehydration.
Prevention is not as simple as rinsing produce. The FDA’s Cyclospora guidance notes that common antimicrobial chemical treatments are not effective against Cyclospora. Federal health officials still recommend thoroughly washing hands and fresh produce and following safe food handling practices, but the CDC cautions that washing alone cannot guarantee removal of the parasite.
That difficulty is part of what has made federal research so important. USDA Agricultural Research Service records have listed Beltsville projects focused on developing Cyclospora viability assays and methods to improve recovery and detection of the parasite. Another USDA research report describes work using parasite surrogates to study Cyclospora and testing filtration systems designed to reduce contamination in agricultural water.
Researchers now fear that specialized expertise could disappear along with the projects. One USDA employee told POLITICO, “They will have no parasitologists,” before adding, “There will be a big knowledge gap.”
Joelle Mosso of the Western Growers Association raised a similar concern. “The bigger impact is that there are very few people in the world that study these [parasites],” she told POLITICO. “It’s not just replacing the lab. It takes decades to build expertise.”
Moving laboratory materials presents another challenge. Barbara Kowalcyk, an associate professor at George Washington University’s Milken Institute of Public Health, told POLITICO, “The food safety lab at BARC [has] isolates that are in minus 80 degree freezers that they’re going to have to figure out how to transport.”
“Do you want them shipping highly pathogenic strains of bacteria in a truck across the country?” she asked.
Former FDA Center for Food Safety and Applied Nutrition director Susan Mayne summed up why losing momentum on the research could have consequences long after the current Cyclospora outbreak ends.
“Cyclospora is a uniquely challenging organism to deal with,” Mayne told POLITICO. “Our science is less sophisticated and less advanced.”
With confirmed infections already far above last year’s seasonal count, scientists say the unanswered questions surrounding Cyclospora make the ability to study, detect and understand the parasite increasingly important to protecting the nation’s food supply.
