Cyclospora Outbreak: What to Know as Cases Rise Across 31 States

Health authorities across the United States are currently monitoring an increase in cases of cyclosporiasis, a gastrointestinal illness caused by the microscopic parasite Cyclospora cayetanensis. Recent reports indicate that the parasite has been identified in at least 31 states, prompting concern among public health officials and the general public alike.

Cyclospora is a single-celled parasite that infects the small intestine. It is typically spread when a person consumes food or water that has been contaminated with feces containing the parasite. Unlike many other foodborne illnesses, it is not spread directly from person to person; it must have time to develop in the environment before it becomes infectious to another human.

The primary symptom of a Cyclospora infection is watery, often explosive, diarrhea. This symptom can be sudden and severe. Other common symptoms include loss of appetite, significant weight loss, cramping, bloating, nausea, and fatigue. Some individuals may also experience low-grade fevers and vomiting. The onset of symptoms typically occurs about one week after the ingestion of the contaminated item, although it can range from a few days to two weeks.

One of the most challenging aspects of cyclosporiasis is the duration of the illness. If left untreated, the symptoms can last for several weeks or even months. Patients often describe a cycle of improvement followed by a recurrence of symptoms, which can lead to significant exhaustion and dehydration. Because the parasite is not a bacteria or a virus, standard tests for common foodborne illnesses do not detect it. Healthcare providers must specifically order a test for Cyclospora to reach an accurate diagnosis.

Historically, outbreaks of Cyclospora in the United States have been linked to the consumption of imported fresh produce. Contaminated leafy greens, fresh herbs like cilantro and basil, snow peas, and raspberries have been identified as common vehicles for the parasite in previous years. The parasite is hardy and can survive in the environment for extended periods, making it difficult to eliminate from produce once contamination occurs. Because these items are often eaten raw, there is no “kill step”—such as cooking—to neutralize the parasite before consumption.

Public health experts emphasize that while the parasite is concerning, it can be treated with a specific combination of antibiotics, typically trimethoprim-sulfamethoxazole (also known as Bactrim, Septra, or Cotrim). Individuals who suspect they have been infected should reach out to their primary care physician, especially if they are experiencing signs of severe dehydration, such as dry mouth, dizziness, or a decrease in urination.

Preventing Cyclospora infection primarily relies on food safety hygiene. While washing produce is an important part of food preparation, the CDC notes that it may not be enough to remove Cyclospora entirely. The parasite can be difficult to wash off due to its microscopic size and its ability to attach to the surfaces of leaves and crevices in fruit. Consumers are encouraged to maintain high standards of kitchen hygiene, including washing hands thoroughly with soap and water, and to remain aware of any food safety alerts or recalls issued by the FDA or local health departments.

As the investigation into the current multi-state cases continues, officials are working to trace the source of the contamination. Tracking the supply chain of fresh produce can be complex, as products are often distributed across broad geographical areas. Health departments in the affected states continue to conduct interviews with patients to determine if specific food items were consumed in the days leading up to their illness.

In the meantime, the public is urged to stay informed about local health alerts and to follow guidance provided by regional health authorities. While this outbreak is widespread, the risk to the average healthy individual can be mitigated by staying vigilant about food sources and reporting persistent digestive issues to a medical professional.

Consult a healthcare professional.