Hawaii Reports Cyclospora Cases Amidst U.S. Surge
Hawaii is now reporting cyclospora cases as the United States experiences a historic upsurge in infections caused by this foodborne parasite. Despite federal officials asserting that recalled produce linked to the largest outbreak is no longer available to consumers, the problem persists.
According to the latest data from the Centers for Disease Control and Prevention (CDC), updated on Tuesday, there are 18,445 laboratory-confirmed cyclosporiasis cases reported since May 1. This figure marks an increase of 1,265 from last week, which had 17,180 confirmed cases. Cases have now been confirmed in 49 states and the District of Columbia.
Hawaii had previously been one of the few states absent from the CDC’s national map. However, Hawaii health officials have now confirmed multiple cyclosporiasis infections in the state.
The CDC’s national map shows State Cyclospora Counts as Hawaii has been added.
In the current data, Michigan is the hardest-hit state with between 4,000 and 6,999 confirmed cyclospora cases. Hawaii, a new addition to the CDC’s map, has between 1 and 49 confirmed cases.
According to the CDC, cyclospora has been confirmed in all states, except Delaware. Delaware officials have reported probable cases, though these are not indicated on the CDC’s map. Sean Dooley, Chief of Public Affairs from Delaware’s Department of Health and Social Services, noted, “Delaware is not exempt from cyclospora activity this season. The state has identified 13 probable Cyclospora cases.” He explained that whole-genome sequencing is required for case confirmation, a process not routinely performed in Delaware.
The rise in reported cases continues despite federal regulators’ reassurances that iceberg lettuce linked to a major multistate outbreak has exited the food supply. The Food and Drug Administration (FDA) and the CDC have indicated that the recalled products’ shelf lives have expired and are no longer in stores or restaurants. As of August 27, more than 11,400 illnesses across 20 states have been connected to the lettuce outbreak, including 495 hospitalizations and two deaths.
Furthermore, the CDC is investigating additional cyclospora clusters beyond those tied to Mexico-sourced processed iceberg lettuce. Some new cases might be related to separate outbreaks that have yet to be identified.
Health officials noted that increasing case counts do not necessarily reflect new exposures at the same rate. Cyclospora surveillance faces significant reporting delays, and the CDC points out that the timeline from symptom onset to case confirmation and reporting can take about six weeks.
What Is Cyclospora?
Cyclospora cayetanensis is a microscopic parasite inducing the intestinal illness cyclosporiasis. Infection occurs after consuming contaminated food or water, often through raw fresh produce. Unlike many gastrointestinal illnesses, cyclospora generally isn’t transmitted directly from person to person. The parasite requires environmental maturation before becoming infectious. Most U.S. cases appear during spring and summer. The CDC outlines the domestic cyclospora season from May 1 to August 31, although case reporting can extend due to delays.
Cyclospora Symptoms
The main symptom of cyclosporiasis is persistent watery diarrhea. Patients may also experience stomach cramps, bloating, nausea, loss of appetite, fatigue, weight loss, and increased gas. Some individuals develop vomiting or a mild fever. Symptoms usually start about a week after exposure but may appear between two days and two weeks later. Without treatment, illness can persist for weeks, showing a relapsing pattern where symptoms improve before returning.
What Products Have Been Recalled?
The largest outbreak this year was linked to processed iceberg lettuce from central Mexico, distributed by Taylor Farms de Mexico. A recall was announced on July 17 after illnesses in multiple states were associated with the product. Despite the recall, a Taylor Farms spokesperson mentioned no positive cyclospora test on their products.
Federal officials have repeatedly highlighted that the recalled items aren’t expected to be available anymore. The CDC confirmed the products’ best-by dates have passed, while FDA officials are confident that affected iceberg lettuce has been removed from the market.
Hawaii health officials noted that the recalled lettuce wasn’t sold or distributed in the state. Investigators are ongoing in determining if Hawaii’s cases link to other multistate outbreaks or a separate source.
How This Cyclospora Season Compares to Last Year
This year’s outbreak dwarfs recent seasons. CDC data report 18,445 laboratory-confirmed cases since May 1, alongside 990 hospitalizations and two deaths. In the May-August period of 2025, there were 1,180 cases nationwide. Public health experts caution that even record figures may underestimate the outbreak’s scale, as many infections remain undiagnosed. People might recover without medical care or without specialized testing to detect cyclospora.
As the 2026 cyclospora season concludes, health agencies expect case totals to continue increasing in the coming weeks while more reports are processed and outbreak clusters are investigated.