Cyclospora Case Data

What to know

Cyclosporiasis is a gastrointestinal infection caused by the parasite Cyclospora cayetanensis. Most cases in the United States occur in spring and summer. Learn more about how CDC collects cyclosporiasis data and investigates outbreaks.

Cases acquired in the U.S.

CDC has received reports of 20,996 laboratory-confirmed cases of cyclosporiasis acquired in the United States with symptom onset dates during the 2026 cyclosporiasis season (May 1–August 31, 2026). For comparison, 1,180 cases were reported in the United States between May 1 and August 31, 2025.

These data include the cases reported in the multistate outbreak linked to iceberg lettuce that recently ended. The data also include cases not linked to that outbreak. Multiple jurisdictions have reported an increase of cases compared with the same period in 2025.

May 1 - August 31, 2026:

These people became sick in the United States and did not report any international travel during the 14 days before they got sick.

State health departments may have more information about the situation in their jurisdictions. Additionally, states may report higher case counts than CDC because they may include cases that do not meet CDC's formal reporting criteria.

There were 13,002 laboratory-confirmed cases of cyclosporiasis reported to CDC requiring further investigation to determine whether they were acquired in the United States or during travel.

U.S. case locations

CDC has received reports of 20,996 laboratory-confirmed cases of cyclosporiasis acquired in the United States with symptom onset dates during the 2026 cyclosporiasis season (May 1 - August 31, 2026). The map shows the states in which these people lived at the time of reporting. Potential Cyclospora infections are typically investigated by the state or local health department where people live, even if they were exposed to the parasite in another state. Cyclosporiasis cases may not be limited to the locations of known cases. The true number of people sick with cyclosporiasis is likely higher than the number reported. This is because some people recover without medical care and are not tested for Cyclospora.

Note: Hover over the map to see the range of cyclosporiasis cases for each state.

These data include case data reported directly to the CDC Cyclospora program. Case counts may not match exactly those listed in the Nationally Notifiable Diseases Surveillance System tables. New York State includes case reports from New York City. In Pennsylvania, cases are reported voluntarily. Data are preliminary and subject to change. For questions related to the number of cases reported in each state, contact that state's health department.

U.S. cases by symptom onset

The chart below, called an epi curve, shows laboratory-confirmed Cyclospora cases with symptom onset dates between May 1 - August 31, 2026, that were acquired in the United States.

Daily case counts are preliminary and subject to change. The true number of people sick with cyclosporiasis is likely higher than the number reported. This is because some people recover without medical care and are not tested for Cyclospora. It takes about six weeks from the start of symptoms to when CDC receives the case information.

How we use epi curves

An epi curve helps public health investigators monitor an outbreak and understand whether illnesses continue to occur or have stopped. This information can guide decisions about public health actions.

Cases acquired outside the U.S.

These cases are in addition to those acquired in the United States.

May 1 - August 31, 2026:

These people became sick after eating food or drinking water while they were traveling outside the United States during the 14 days before they got sick.

Resources

• How Data Are Collected for Cyclosporiasis
• FDOSS Home | Foodborne Disease Outbreak Surveillance System (FDOSS)| CDC
• Foodborne Outbreak Surveillance Data
• Reporting a Foodborne Disease Outbreak (general public)
• Report a Problem with Food