Cyclosporiasis Outbreak Hits 32 States With Nearly 3,000 Reported Cases

Geographic Impact and Case Distribution

The outbreak has affected a broad swath of the country, with cases reported from California to Florida and Texas. The Midwest and Northeast appear to be the most significantly impacted regions. Michigan is currently the hardest-hit state, reporting 1,562 cases as of July 10, a figure officials note is 31 times higher than the state’s typical annual average. Other states experiencing notable case numbers include:

Additional states, including Florida, are reporting more than 100 cases, while California has reported between one and 10 cases. Nationally, 86 hospitalizations have been confirmed, though no deaths have been linked to the current outbreak.

Symptoms and Clinical Risks

Cyclosporiasis is characterized by gastrointestinal distress. The CDC describes the most common symptom as watery diarrhea, which can be frequent and sometimes explosive. Other reported symptoms include nausea, vomiting, abdominal pain, and bloating. Dr. Bruce Vanderhoff, director of the Ohio Department of Health, emphasized that the condition is a “serious illness that can cause dehydration and require people to seek emergency medical care.” While the illness is not typically life-threatening, if left untreated, symptoms may persist from several days to over a month and can occasionally return after appearing to dissipate. The illness affects a wide age range, with reported patients currently spanning from 5 to 88 years old.

The Challenge of Tracing the Source

Investigators are attempting to identify the source of the outbreak by interviewing patients about their recent diets. However, these efforts are complicated by the incubation period of the parasite. Symptoms typically appear about one week after infection, but this window can range from two days to two weeks or longer, making it difficult for patients to accurately recall everything they consumed. While the exact source of this current outbreak remains unknown, the CDC notes that previous U.S. outbreaks of cyclosporiasis have been linked to imported fresh produce, specifically raspberries, basil, cilantro, snow peas, and various types of lettuce.

Prevention and Treatment Guidelines

Public health officials recommend several food safety practices to minimize the risk of infection. Because the parasite is often transmitted through food or water contaminated with feces, the CDC advises:

• Thoroughly washing all fresh produce, including herbs.
• Cutting away bruised or damaged parts of fruits and vegetables.
• Refrigerating pre-prepared or pre-cut produce.
• Washing hands with soap and water before and after handling raw produce.

For those preparing food at home, cooking produce is an effective mitigation strategy, as heating food to 158 degrees Fahrenheit or higher kills the parasite. Michigan health officials have specifically advised restaurants and kitchens to ensure greens are thoroughly washed. For individuals who contract the parasite, the infection is typically treated with a 10-day course of the oral antibiotic trimethoprim-sulfamethoxazole, commonly known by brand names including Bactrim, Septra, and Cotrim. Health officials encourage anyone experiencing severe diarrhea or signs of dehydration to seek medical attention.

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