This summer, a parasite-driven illness causing severe gastrointestinal distress has dominated headlines in the U.S., significantly reducing the consumption of iceberg lettuce. However, recent data from the U.S. Centers for Disease Control and Prevention and state authorities indicate that the spread of new infections might be slowing.
By August 18, the CDC had recorded over 15,000 confirmed cases of cyclosporiasis since May. This marks an increase of more than 14,000 cases when compared to the same period from May 1, 2025, to August 31, 2025. The CDC reports that 828 individuals have required hospitalization, and there have been two fatalities related to the infection.
There are potentially thousands more cases not yet confirmed, as some states are using different tracking methods than the CDC. For instance, Michigan officials reported 14,277 cases since June. The actual number nationwide could be even higher because many individuals with cyclosporiasis may experience mild symptoms and thus might not seek medical attention or testing.
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The outbreak has been traced back to iceberg lettuce, especially those produced by Taylor Farms de Mexico. This lettuce was distributed in stores and Taco Bell restaurants throughout the U.S. before being recalled. Cyclosporiasis results from a parasite that spreads through food and water contaminated with human feces. The Food and Drug Administration, responsible for food safety, stated it is “confident that all recalled iceberg lettuce related to this specific Cyclospora outbreak is off the market.”
New case numbers appear to be decreasing. CDC data reveal a peak in cases during early to mid-July, followed by a substantial decline in new infections. Michigan, one of the most affected states, has also noticed a reduction in new cases recently, though they continue to report some instances.
There is a possibility that many new infections are not yet reflected in the data. Symptoms of cyclosporiasis can take over two weeks to manifest, and new cases are typically recorded in CDC data after approximately six weeks.
Symptoms include severe, watery diarrhea, fatigue, and nausea, which can persist from a few days to a month or longer without treatment.
To avoid infection, the CDC advises washing hands and fresh produce thoroughly under running water before consumption, preparation, or cooking. The Cyclospora parasite is difficult to eliminate, requiring food to be cooked to at least 158 degrees Fahrenheit (70 degrees Celsius) to ensure safety. On August 6, Michigan state officials suggested that people can resume normal salad preparation and consumption practices.
“The broad, precautionary recommendation to avoid bagged salad mixes during the Cyclospora outbreak is no longer in effect,” Michigan officials stated in an August 6 announcement. “Residents may resume their usual food handling practices and make choices based on their individual risk tolerance.”
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