Cyclosporiasis, an illness characterized by explosive diarrhea, is spreading across at least 17 U.S. states, though the true number of cases is likely higher due to reduced CDC surveillance and underreporting. The parasite responsible, Cyclospora cayetanensis, has historically been found on fresh fruits, vegetables, and herbs, with infections peaking during summer months.
Transmission and Symptoms
According to Dr. Michael Cappello, professor and chair of the Department of Epidemiology at Yale School of Public Health, infection typically occurs after ingesting produce contaminated with human sewage or waste. “It’s a fecal-oral route,” added Dr. Jennifer Horney, professor of epidemiology at the University of Delaware, emphasizing that the disease does not spread person to person. Symptoms include loud, explosive diarrhea, bloating, fatigue, nausea, and stomach pain.
Historical Sources and Current Uncertainty
While the exact source of the current outbreak remains unknown, past outbreaks have been traced to raspberries, basil, cilantro, lettuce, parsley, snow peas, and green onions. “We’ve had outbreaks linked to these kinds of products in the past,” noted Dr. Donald W. Schaffner, a food science professor at Rutgers University. However, he cautioned that future outbreaks could involve different produce. Cappello explained that the contamination often occurs during growing, irrigation, or processing, and because produce is typically consumed raw, cooking—which would kill the parasite—is not an option for many items.
Protection Through Washing
Experts stress that thorough washing of produce under running cold water is the best preventive measure. “You really have to wash it well,” Cappello said, adding that soap or special sprays are unnecessary. A salad spinner can help remove water and debris. However, Schaffner noted that washing is not foolproof, as Cyclospora can hide in crevices, such as those in raspberries. Cooking produce, while effective, alters texture and taste.
Public Health Infrastructure Under Strain
Despite the outbreak, experts advise against avoiding fresh produce altogether due to its nutritional benefits. “I am not changing my consumption habits,” Schaffner stated. However, they urge those with severe symptoms to seek medical care, as antibiotics are available. The outbreak highlights the importance of robust public health surveillance. Schaffner expressed disappointment in the lack of CDC information, linking it to federal staffing cuts. Cappello called for sustained investment in foodborne illness surveillance programs to prevent future outbreaks.
