Cyclosporiasis Outbreak Hits 47 States — 15,716 Cases, 2 Dead, Iceberg Lettuce Recalled

The United States is experiencing its largest cyclosporiasis outbreak on record, with the CDC reporting 15,716 lab-confirmed cases across 47 states as of August 17, 2026. The outbreak has hospitalized 828 people and killed two. Federal health officials have linked 9,481 cases in 17 states to recalled iceberg lettuce from Taylor Farms de Mexico.

Michigan remains the epicenter. State health officials reported 13,909 cases, 314 hospitalizations, and both deaths as of August 13. The Michigan figure includes all reported state cases, including infections not yet assigned to the lettuce-associated cluster and cases delayed by a laboratory backlog.

Cyclosporiasis is an intestinal infection caused by a parasite called Cyclospora cayetanensis. It spreads through contaminated food or water. The incubation period averages one week, and symptoms include watery diarrhea, abdominal cramps, nausea, and fatigue. Without treatment, the infection can last for weeks or months and cause significant weight loss.

What Is Cyclosporiasis and Why Is It Spreading

Cyclosporiasis is caused by a single-celled parasite that contaminates produce and water. Unlike bacteria, it is not killed by routine washing. Only heating food to at least 158 degrees destroys the parasite. That makes fresh produce like lettuce, cilantro, and raspberries a common vector.

Lynette Johnston, assistant professor and food safety extension specialist at NC State University, explained the challenge: "Cyclospora is not a bacteria. Many of our foodborne illnesses we think of them as bacteria. We can handle them in a little bit different way. Their control and prevention are certainly different. Cyclospora is definitely a hardier organism that is harder to control. The other thing is we know less about this organism."

Federal investigators traced the outbreak to iceberg lettuce grown in central Mexico by Taylor Farms. The recall was issued on July 17, 2026, and covered lettuce sold at retail stores, served in restaurants, and distributed to food service customers.

Michigan: The Center of the Outbreak

Michigan health officials have reported the highest case count in the country. As of August 13, the state had logged 13,909 cases, 314 hospitalizations, and both deaths. The state's figures include a backlog of cases reported through a new laboratory reporting system.

The two deaths both occurred in individuals with significant underlying health conditions. Both had become ill before the FDA's July 17 recall.

Timeline: How the Outbreak Unfolded

Frequently Asked Questions

What is cyclosporiasis? It is an intestinal infection caused by the parasite Cyclospora cayetanensis, spread through contaminated food or water.

What foods should I avoid? Recalled iceberg lettuce from Taylor Farms de Mexico. Washing produce reduces risk but does not eliminate the parasite.

How many people have been affected? 15,716 lab-confirmed cases and 828 hospitalizations across 47 states as of August 17, 2026.

Which states are hardest hit? Michigan, with 13,909 cases and both deaths.

How is cyclosporiasis treated? Antibiotics. Healthy people may recover without treatment, but treatment shortens the illness.