Cyclosporiasis Outbreak: What to Know About the Current Parasitic Infection

As of July 9, the Centers for Disease Control and Prevention (CDC) has confirmed 843 cases of cyclosporiasis across 31 states, with 86 hospitalizations reported since May 1. Cyclosporiasis is an intestinal illness caused by the microscopic parasite *Cyclospora cayetanensis*, which is typically transmitted through food or water contaminated with human feces. While the specific source of this year’s outbreak remains under investigation, health officials are monitoring the situation as an additional 1,500 cases are currently under review.

Understanding Cyclospora Transmission

The *Cyclospora* parasite is most frequently introduced into the food supply chain during the growing, harvesting, or processing of fresh produce. According to the CDC, the parasite is remarkably resilient and can survive in environments that would kill other pathogens.

In previous years, outbreaks of cyclosporiasis have been linked to imported fresh produce, including raspberries, basil, cilantro, snow peas, green onions, and mesclun lettuce. Because the parasite is “sticky” and resistant to many standard cleaning methods, health experts emphasize that rinsing or scrubbing produce is often insufficient to remove the parasite entirely.

Symptoms and Clinical Diagnosis

The primary symptom of cyclosporiasis is watery diarrhea, which is often described as frequent and explosive. Because the incubation period for the parasite is typically about one week after exposure, linking specific meals to an infection can be difficult.

According to Katelyn Jetelina, an assistant professor adjunct of epidemiology at the Yale School of Public Health, the true number of infections is likely significantly higher than the official count. Many individuals recover without seeking medical attention, and those who do consult a doctor may not be tested because diagnosis requires multiple stool samples collected over several days, which can be both expensive and time-consuming.

Other common symptoms include:

• Loss of appetite and weight loss
• Stomach cramps, bloating, and gas
• Nausea and vomiting
• Fatigue, body aches, and headaches
• Low-grade fever

Severe cases are treated with antibiotics, as the infection does not typically resolve without medical intervention.

Food Safety and Prevention Strategies

While investigations into the current outbreak are ongoing, no official product recalls have been issued by the U.S. However, food safety guidelines remain the most effective defense against infection. The most reliable way to eliminate *Cyclospora* is through heat. The parasite cannot survive when food reaches an internal temperature of at least 158 degrees Fahrenheit. For those concerned about raw produce, cooking vegetables before consumption provides a layer of safety that washing cannot guarantee. Standard hygiene practices remain essential during the outbreak:

• Wash hands thoroughly with soap and water before and after handling any fresh produce.
• Regularly sanitize cutting boards, knives, and kitchen utensils to prevent cross-contamination.
• Consider avoiding raw, high-risk produce items—such as leafy greens and herbs—if you are at a higher risk for severe illness.

As of mid-July, major restaurant chains have not publicly announced widespread changes to their supply chains or menu offerings in response to the outbreak. While some local media reports indicated that individual locations of certain fast-food chains took preventative measures, there has been no coordinated industry-wide shift in procurement protocols.