A surge of Cyclospora cayetanensis infections is spreading across the U.S., causing severe and explosive diarrhea that can last for weeks.
This outbreak is significant because the parasite is often linked to fresh produce consumed at home, making it difficult for consumers to avoid contamination without official recalls. The infection requires specific medical treatment and can lead to prolonged illness.
Health officials said the cause is a microscopic parasite that spreads via food or water contaminated with feces, according to Smithsonian Magazine staff [1]. The parasite is frequently associated with fresh produce grown on farms [1], [3].
The scale of the outbreak is widespread. Between May 1 and June 16, 145 cases of cyclosporiasis were reported across 17 states [4]. However, other reports indicate a much larger impact in specific regions. Michigan is experiencing its largest outbreak of cyclosporiasis, with more than 700 cases reported, according to a Yahoo News health reporter [2]. While some reports suggest the majority of cases are in New York, the high volume in Michigan marks it as a primary center of the surge [2], [3].
Notable clusters of the infection have appeared in New Jersey, Pennsylvania, New York, and Michigan [2], [4], [5]. The symptoms are characterized by severe gastrointestinal distress. Because the parasite is hardy and can survive various conditions, it often reaches consumers through the commercial food supply chain.
Medical professionals said the illness is distinct from typical food poisoning due to its duration. Patients may suffer from recurring bouts of diarrhea and fatigue for several weeks if the infection is not properly treated with the correct antiparasitic medication.
“Cyclospora cayetanensis is a microscopic parasite that spreads via food or water contaminated with feces.”
The discrepancy in case numbers between state-level reporting and total counts suggests a significant underreporting of cyclosporiasis or a rapidly evolving cluster. Because the parasite is linked to produce, this outbreak highlights vulnerabilities in the agricultural supply chain and the difficulty of tracing contaminated leafy greens or berries across multiple state lines.
