Michigan cyclosporiasis outbreak surpasses 10,000 cases as health officials investigate recalled lettuce and nationwide infections.
A record-breaking outbreak of cyclosporiasis has infected more than 10,000 people in Michigan, making it the largest outbreak ever recorded in the state and one of the most significant foodborne illness events in recent U.S. history.
According to the Michigan Department of Health, more than 10,000 confirmed cases have been reported during the current outbreak investigation. With Michigan’s population of about 10.1 million people, health officials estimate that approximately one in every 1,000 residents has contracted the illness over the past three months.
Cyclosporiasis is an intestinal illness caused by the microscopic parasite Cyclospora cayetanensis. People become infected by consuming contaminated fresh produce or water, and the illness commonly causes severe diarrhea, along with stomach cramps, nausea, vomiting, fatigue, loss of appetite, weight loss, and dehydration.
As part of the ongoing investigation, Taylor Farms has recalled iceberg lettuce believed to be linked to the outbreak. Health officials say it is likely that many contaminated products had already been consumed or removed from store shelves before the recall was issued.
Last week, U.S. Health and Human Services Secretary Robert F. Kennedy Jr. said authorities have largely contained the outbreak.
“We do have the outbreak under control,” Kennedy said, referring to the lettuce recall and ongoing response efforts.
However, public health officials caution that new cases are still being reported, as symptoms of cyclosporiasis can take days or even weeks to develop after exposure. Thousands of additional infections were reported across the United States over the past week, indicating that the outbreak’s impact is still unfolding.
Investigators are continuing to trace the source of infections, but identifying contaminated food products remains a significant challenge. The Cyclospora parasite is difficult to detect through routine food testing, and investigators often rely on interviews with patients, who may be asked to recall what they ate weeks before becoming ill.
Health experts say these delayed symptoms make it harder to identify common sources and prevent further spread.
According to the U.S. Centers for Disease Control and Prevention (CDC), cyclospora infections typically increase during the spring and summer months, with the usual season running from early May through the end of August. While seasonal increases are expected, case numbers in 2026 are significantly higher than normal, prompting heightened surveillance by federal and state health agencies.
Health officials advise consumers to check recall notices, avoid eating recalled products, and practice safe food handling, including thoroughly washing fresh fruits and vegetables, although washing alone may not completely remove the parasite.
Authorities continue to monitor the outbreak closely as they work to identify additional sources of contamination and prevent further infections across the country.
