Michigan health officials detected the first signs of a cyclosporiasis outbreak in late June 2025 and immediately notified federal agencies. They released a public notice on July 1, ahead of the holiday weekend, warning home cooks and commercial kitchens about potentially contaminated produce. Despite working through the holiday without a day off, the outbreak has continued to escalate.
Cyclosporiasis, a parasitic illness causing weeks of explosive diarrhea and vomiting, can take weeks to appear, so officials cannot yet determine if their warnings have been effective. The outbreak is now the largest in U.S. history, with Michigan reporting over 5,000 cases and 102 hospitalizations as of Friday—a 1,300-case increase from Wednesday. In a typical year, Michigan sees only 40 to 50 cases.
Funding cuts weaken response
The outbreak comes after the Trump administration cut $12 billion in public health funding in March 2025, affecting laboratory capacity, disease monitoring, and outbreak investigation. Half of U.S. states sued to claw back the funding, but those not included in the lawsuit did not receive the funds, leading to delays, layoffs, and uncertainty.
Michigan lost an entire regional laboratory and 23 employees in the state bureau of infectious diseases, while local health departments lost 123 staff due to federal funding cuts. The CDC has lost about one-third of its staff, and most permanent leadership positions remain vacant.
“If you’re down one member of the soccer team, you might not be able to trace that back to every goal you lost, but you’re going to see an impact,” said Susan Kansagra, chief medical officer at the Association of State and Territorial Health Officials (ASTHO). “It’s going to catch up with you over time, and I think that is what we are starting to see now.”
Federal response lags
Communication between federal and state agencies has suffered. “Communication has been somewhat less than we have experienced in previous outbreaks,” said Natasha Bagdasarian, Michigan’s chief medical executive. “In previous outbreaks, we have received additional assistance from CDC, and we have not in this particular outbreak.”
The CDC issued a health advisory to providers on Tuesday, two weeks after the first signals emerged. HHS Secretary Robert F. Kennedy Jr. made his first public comments about cyclospora on Friday, downplaying the severity. “There are cyclospora outbreaks every summer,” he said on a Tampa-based podcast, without noting the dramatic increase in cases. He also denied cuts to surveillance programs, despite evidence to the contrary.
Testing and surveillance challenges
In 2025, the administration made cyclospora and several other pathogens optional for reporting to FoodNet, a national foodborne-illness tracker. This will hinder identification of trends and risk factors, said Melanie Firestone, assistant professor at the University of Minnesota School of Public Health. However, she noted that FoodNet is not the primary pathway for outbreak identification; state and local funding is more critical.
Michigan public health staff have spent over 1,000 hours interviewing patients. The state has four specialists in stomach illnesses, with dozens more pulled from other projects. The lab has “far exceeded” its cyclospora budget, with about 2,000 samples sequenced or awaiting sequencing at $122 per test.
Testing costs several hundred dollars at the doctor’s office, and insurance may not cover it fully. “Even people with insurance have been declining testing because of high copays,” Bagdasarian said. “There will be more people falling off Medicaid coverage, and so it’s going to be harder for us to even know how many cases are out there.”
Source of outbreak
Lettuce from Taylor Farms is likely linked to the outbreak, according to reports from the Washington Post and Bloomberg News. Taylor Farms, based in California with locations in Mexico, was linked to a cyclospora outbreak at Olive Garden and Red Lobster in 2013 and an E. coli outbreak from slivered onions at McDonald’s in October 2024. The CDC pointed to a shredded iceberg lettuce supplier in Mexico, naming Taco Bell as an affected restaurant, but the outbreak probably extends beyond one chain.
“As we look at where people could have come into contact with this contaminated material, there is no one single place that has jumped out at us,” Bagdasarian said. “It’s more about ‘where did contamination occur upstream?’ – and many of these producers will supply not only restaurants and fast-food chains but also grocery stores.”
