The number of patients in multiple outbreaks of Cyclospora infections continues to grow, with the Centers for Disease Control and Prevention reporting more than 1,800 additional patients compared to a week ago.
Since May 1, the CDC has received reports of 15,716 laboratory-confirmed reports of infections from the Cyclospora parasite. That is up from the 13,895 patients logged a week ago. The CDC is reporting at least 828 hospitalizations, with two patients having died in Michigan. The sick people are spread across 47 states, Washington D.C. and Puerto Rico.
For comparison purposes, the CDC logged 1,180 cases of Cyclospora infections from May 1 through Aug. 31 in 2025.
Timeline for illnesses in 2026
In addition to the 15,716 confirmed patients so far this year, the CDC is aware of another 11,841 patients who need lab work to confirm their infections.
Also, there are likely many more patients who have not been identified at all because for every one person who is confirmed in a Cyclospora outbreak there are 83 who go completely undetected. This is because some don’t seek medical attention and others are not specifically tested for Cyclospora parasites.
Of the patients identified so far, the people became sick in the United States and did not report any international travel during the 14 days before they became ill.
They patients range in age from 1 to 99 years old, with a median age of 46, and 57 percent are female. The median illness onset date was July 7, with a range from May 1 to Aug. 13.
The CDC is also tracking an outbreak of Cyclospora infections related to iceberg lettuce products from a Taylor Farms growing operation in Central Mexico. The most recent patient count in that outbreak has not been updated since last week. As of then there were 9,481 patients.
About Cyclospora
Anyone who has developed symptoms of Cyclospora infection, and has reason to believe they have been exposed to the parasite, should seek medical attention. Specific tests are required and antibiotics are used to fight the parasite.
Cyclospora infection can cause severe abdominal pain, watery diarrhea, nausea, vomiting, body aches, and fatigue. Symptoms can develop between two and 14 days after exposure. Though symptoms can be severe enough to send people to the hospital, it’s rare for people to die from Cyclospora infections.
Symptoms can last for a month or more and can reoccur for several more months if not treated.
Cyclospora is a type of protozoa, which is a single-celled organism. It is transmitted when people somehow ingest contaminated feces, typically through contaminated food or water. It can be spread only through human waste, unlike E. coli and salmonella, which can also be spread from animal fecal matter.
Previous U.S. outbreaks of cyclosporiasis have been linked to various types of fresh produce, including lettuce, basil, cilantro, mesclun lettuce, raspberries, and snow peas.
Food safety experts say washing produce will not remove the parasite because it becomes embedded in the flesh of the produce. Also, chlorine will not kill the parasites.