Suspected cyclosporiasis cases rise to over 20K

Cyclosporiasis is a disease caused by the parasite cyclospora and is most common during the spring and summer months. People can be infected with the parasite if they consume food or water that's been contaminated with feces.

Symptoms of the disease include cramps, nausea, loss of appetite, vomiting, fatigue, diarrhea, body aches, low-grade fever, and other flu-like symptoms. Cyclosporiasis can last for a few days to over a month, and symptoms can come in waves, returning more than once after going away.

According to CDC, there have been 13,895 lab-confirmed cases of cyclosporiasis across 47 states between May 1 and Aug. 10. An additional 10,455 cases have been reported but not yet been confirmed by labs.

Ohio and Michigan have seen the worst of the outbreak. On Aug. 13, Michigan's health department reported that it had recorded 13,909 cases of cyclosporiasis, including the first two deaths identified in the outbreak.

So far, only one outbreak has been linked to a common source. The largest outbreak was traced by FDA to recalled iceberg lettuce grown by Taylor Farms in central Mexico.  Almost 9,500 total cases across 17 states are part of this lettuce-linked outbreak. 

Why tracking cyclospora is so difficult

Cyclospora is uniquely difficult to track, monitor, and eliminate. For years, scientists have lacked the funding to better understand the cyclospora parasite, including the ways in which it spreads and how to detect it.

Cyclospora reproduces by releasing oocysts, which are then excreted in human feces and typically end up in the sewage system. According to Joan Rose, a public health water microbiologist who collects sewage water and tests it for harmful pathogens, sewage can overflow into bodies of water or be used directly on crops, which increases the risk of diseases, including from cyclospora. 

Testing for cyclospora in the environment, especially in agricultural water, is also extremely challenging and as a result, it's rarely done. In addition, cyclospora doesn't grow in a lab culture. Scientists often use culture as a way to amplify small bits of bacteria like salmonella or E. coli to detectable levels, but that can't be done for cyclospora, according to Kalmia Kniel, a microbiologist at the University of Delaware.

"This is one of the areas where we really do have a need to advance much faster and research far more, as it continues to be something that we face every summer," said Steven Mandernach, the executive director of the Association of Food and Drug Officials who investigated two cyclospora outbreaks as an Iowa food safety official.

However, Donald Prater, acting deputy commissioner for FDA, said the agency responded swiftly with the information it had on hand, and added that even if the 24-hour rule had been in effect, it wouldn't have made a significant impact on managing the outbreak response.

A lack of funding for FDA and limited staff focused on inspections may have also hindered recent food safety efforts. Currently, FDA only has around 440 staff charged with inspecting over 300,000 registered animal and human food facilities both in the United States and abroad. In 2025, the agency made around 1,100 visits to foreign food plants and cited significant lapses in around 80 of them.

"FDA inspections really are the first line of defense for mitigating outbreaks. If FDA isn't routinely going out to food facilities, it's just completely blind," said Meridith Seife, the lead author on an HHS Inspector General report on FDA inspections of U.S. facilities. "It's unable to ensure that those facilities are complying with the laws, with regulations, and that the food that they handle is safe."

In response, Emily Hilliard, senior press secretary for HHS, said FDA is "actively working to expand staffing at foreign posts" and that the agency has a "comprehensive oversight system, which prioritizes resources based on risk and deploys personnel where they have the greatest public health impact."

Other health experts have also highlighted the fact that day-to-day food safety is primarily the responsibility of food companies, not regulators.

Because FDA inspections happen infrequently, "the day-to-day operations and management of food safety is really on the company rather than on the regulatory agency," said Don Schaffner, chair of the department of food science at Rutgers University.