Two people in Michigan have died from cyclosporiasis in what is now the largest documented U.S. outbreak of the parasitic infection, with more than 18,000 cases reported across at least 45 states since early May. The Michigan Department of Health and Human Services said both individuals had significant underlying health conditions that may have been worsened by the infection and dehydration. Federal investigators have tied a nine-state cluster of cases to shredded iceberg lettuce from Taylor Farms de Mexico, a supplier that serves Taco Bell restaurants and has issued a voluntary recall.
How big is the outbreak, and where is it hitting hardest?
Michigan alone has reported 11,234 cases, including 193 hospitalizations, according to the state health department. Nationally, at least 6,707 cases have been laboratory-confirmed, with about 11,500 additional suspected cases still under investigation. The gap between state and federal tallies reflects the time it takes the CDC to confirm and aggregate reports; the agency has said it can take up to six weeks to determine whether a sick person belongs in its count. Health officials also note that most people with a stomach illness never get tested, so the true number of infections is almost certainly higher.
CDC records show the previous high for U.S. cyclosporiasis came in 2018, and even the largest prior counts numbered only in the low thousands. The current surge dwarfs that benchmark.
What is cyclosporiasis, and what does it do to the body?
Cyclosporiasis is caused by the microscopic parasite Cyclospora cayetanensis, which triggers severe watery diarrhea, often with frequent and sometimes explosive bowel movements. According to the CDC, additional symptoms include nausea, vomiting, abdominal pain, and bloating. While the infection is rarely fatal in otherwise healthy people in the U.S., it can cause dangerous dehydration, particularly in vulnerable patients, and untreated illness can drag on for a month or more.
A 2024 review of Cyclospora cayetanensis by Mansfield and Gajadhar in Veterinary Parasitology describes the organism as a food- and waterborne coccidian parasite transmitted by oocysts via the fecal-oral route, primarily through contaminated water or food. The review notes that Cyclospora is considered an emerging pathogen and that underreporting is common because standard diagnostic methods for intestinal parasites often fail to detect it. The same review counted 11 foodborne outbreaks of cyclosporosis in North America between 1990 and 2000 that affected at least 3,600 people, a fraction of the present toll.
Where did the contaminated lettuce come from?
The CDC has linked cases in Michigan and eight other states to shredded iceberg lettuce distributed by Taylor Farms de Mexico, the supplier that provides produce to Taco Bell. In mid-July, the agency announced that the supplier had removed all iceberg lettuce from the U.S. market, though officials said at the time they did not yet know whether the lettuce had also gone to other restaurant chains or grocery retailers. Taco Bell confirmed last month that it had stopped using lettuce from Taylor Farms de Mexico at all of its locations. The supplier also issued a voluntary recall of all iceberg lettuce sourced from central Mexico, advising consumers to discard or return any affected product.
The parasite is endemic to Mexico and other tropical and subtropical regions and typically reaches consumers through fresh produce irrigated with water carrying human waste. Cyclospora does not spread directly from person to person.
Can washing produce remove the parasite?
No. The CDC has stressed that rinsing produce is not a reliable defense; the parasite clings tightly to leafy greens, and ordinary washing does not remove it. A 2021 scoping review of Cyclospora cayetanensis detection and control by Totton and colleagues in Epidemiology and Infection, drawing on 349 primary research studies, found a stark gap in the evidence base: zero publicly available detection-method studies in soil, only two in water, and no studies of how to control Cyclospora on produce before it reaches retail. That research vacuum helps explain why contaminated product can move through the supply chain undetected for long stretches.
How long were consumers exposed before the source was named?
The outbreak began in early May. The CDC did not name the source until mid-July. For roughly eleven weeks, contaminated lettuce was served to customers without any public warning, while federal agencies worked backward through the supply chain to identify the supplier. By the time the recall was issued, two Michigan families had already lost someone to the infection.
Are there other cyclosporiasis outbreaks underway?
Yes. The CDC has noted that it is also investigating other cyclosporiasis outbreaks nationally that are unrelated to the Taco Bell-linked cluster. Separately, the UK Health Security Agency reported a sharp rise in cyclosporiasis infections among travelers returning from Mexico, counting 67 cases in roughly eleven weeks between April 30 and July 15, against an annual average of 93 cases from 2022 through 2025. UK officials are advising travelers to maintain strict food and water hygiene while abroad.
FAQ
What is cyclosporiasis?
Cyclosporiasis is an intestinal infection caused by the microscopic parasite Cyclospora cayetanensis. It produces severe watery diarrhea, nausea, vomiting, abdominal pain, and bloating, and it can cause dangerous dehydration, especially in people with underlying health conditions. Untreated illness can last a month or longer.
How many people have been sickened in the current U.S. outbreak?
More than 18,000 cases have been reported across at least 45 states since early May. Michigan alone has reported 11,234 cases and 193 hospitalizations. Nationally, 6,707 cases have been laboratory-confirmed, with another 11,500 suspected cases under CDC review. Health officials say the true count is likely higher because many infected people never get tested.
Which supplier is responsible for the contaminated lettuce, and what has been recalled?
Taylor Farms de Mexico, a supplier of shredded iceberg lettuce to Taco Bell, has been linked by the CDC to a nine-state cluster of cases. The company removed all its iceberg lettuce from the U.S. market in mid-July and issued a voluntary recall of iceberg lettuce sourced from central Mexico. Taco Bell has stopped using lettuce from the supplier at all of its locations. Consumers have been advised to discard or return any recalled product, and the CDC has warned that washing produce does not reliably remove the parasite.
This article summarizes reporting from naturalnews.com.
