Cyclosporiasis Outbreak: Gastrointestinal Illness Spikes in 31 States

Public health agencies are currently monitoring a significant uptick in cases of cyclosporiasis, a gastrointestinal illness caused by a microscopic parasite. Reports indicate that the infection has spread across 31 states, resulting in dozens of hospitalizations as individuals seek medical care for severe symptoms. While outbreaks of this nature are not uncommon during peak produce seasons, the current geographical spread has prompted increased surveillance from the Centers for Disease Control and Prevention (CDC) and state health departments.

Cyclosporiasis is caused by the parasite Cyclospora cayetanensis. Humans typically become infected after consuming food or water that has been contaminated with feces containing the parasite. Unlike many other foodborne illnesses, Cyclospora is not transmitted directly from person to person; an individual must ingest something that has been tainted, usually through the fecal-oral route in a contaminated environment.

Common symptoms of the illness include frequent, watery diarrhea, loss of appetite, weight loss, stomach cramps, bloating, increased gas, nausea, and fatigue. Some individuals may also experience vomiting or low-grade fevers. Symptoms often appear about a week after ingesting the parasite, though this timeline can vary. If left untreated, the illness can persist for several weeks or even months, with a tendency to relapse, meaning patients may feel better for a few days before symptoms suddenly return.

Historically, outbreaks of cyclosporiasis in the United States have been linked to imported fresh produce. Specifically, leafy greens, fresh cilantro, basil, and berries have been implicated in past years. Because the parasite is robust and can cling to the surfaces of fruits and vegetables, simple rinsing is not always sufficient to remove the threat. The complexity of modern supply chains often makes it difficult for investigators to pinpoint a single source of contamination quickly, leading to the wide distribution of cases across multiple states.

Health officials recommend that anyone experiencing persistent diarrhea or other symptoms associated with the infection contact their primary care physician. Diagnosis requires specific stool testing, as standard laboratory screenings for common bacteria or viruses often do not detect Cyclospora. Treatment typically involves a course of specific antibiotics, which helps to shorten the duration of the illness and prevent further complications.

To reduce the risk of infection, experts emphasize general food safety practices. Thoroughly washing produce is a primary defense, although it does not guarantee complete elimination of the parasite. Furthermore, maintaining proper hygiene in the kitchen—such as washing hands, utensils, and cutting boards after contact with raw produce—is essential. When traveling to regions where the parasite is more prevalent, consumers should exercise caution by drinking bottled or treated water and avoiding raw foods that may have been washed in local water supplies.

As the investigation continues, state and federal agencies are working to trace the origins of the contaminated products. The process involves interviewing patients about their diet over the two weeks prior to the onset of symptoms and conducting environmental testing. By identifying common points of purchase or specific food brands, authorities hope to narrow down the source and issue targeted recalls if necessary. For now, officials advise the public to stay informed through local health department updates and to prioritize food hygiene to limit the spread of the illness.