A parasitic infection known as cyclosporiasis is surging across the United States, with over 3,100 cases reported in 31 states as of July 10, according to data tracked by NBC News. Caused by the Cyclospora cayetanensis parasite, the illness spreads via the fecal-oral route—typically through contaminated fresh produce—and triggers severe, watery diarrhea that can persist for weeks.
Current Surveillance and State-Level Impacts
National surveillance data from the U.S. Centers for Disease Control and Prevention (CDC) indicates that infections have been trending upward since May 1. While the CDC has logged 843 confirmed cases in its primary dataset, it is currently reviewing more than 1,500 additional reports to confirm they are domestically acquired. At least 86 people have required hospitalization.
Impacts vary significantly by region. Michigan is currently reporting an unprecedented spike, with 1,562 cases recorded since late June. According to a spokesperson for the Michigan Department of Health and Human Services (MDHHS), this figure is nearly 25 times the state’s typical annual average of 40 to 50 cases. Ohio has also seen a sharp increase, with 171 of its 397 total cases occurring since late June. Other states, including Illinois, North Carolina, Colorado, and Indiana, are reporting elevated numbers.
Cyclosporiasis is not typically spread person-to-person. The parasite spreads through food and water contaminated with feces from an infected person.
Evaluating the Risk of a Multistate Outbreak
While the rise in cases is clear, health authorities have not yet declared a unified multistate outbreak. The CDC stated in an email to NBC News that it currently lacks evidence of a single, overarching source linking the various clusters. Similarly, a spokesperson for the U.S. Food and Drug Administration (FDA) noted that the agency is monitoring the situation but is not yet characterizing the current numbers as definitively unusual.
Dr. Natasha Bagdasarian, chief medical executive for the state of Michigan, noted that the current hypothesis focuses on contaminated fresh produce. Historically, outbreaks of this parasite have been linked to salad greens, raspberries, basil, cilantro, and snow peas. Investigations into specific suppliers and growers are ongoing.
Recognizing Symptoms and Seeking Care
The primary symptom of a Cyclospora infection is sudden, frequent, and “explosive” watery diarrhea. According to the Cleveland Clinic, additional symptoms include:
- Severe stomach cramping and bloating
- Nausea and vomiting
- Loss of appetite
- Fatigue
Symptoms often appear up to 14 days after ingesting the parasite. A defining characteristic of the infection is its tendency to relapse, where a patient feels better for a few days before symptoms return. While most healthy individuals recover without intervention, the CDC notes that the infection can be treated with a combination antibiotic for those who do not clear the parasite on their own.
Proactive Prevention Strategies
The MDHHS emphasizes that cooking food to at least 158 degrees Fahrenheit is the most effective method for destroying Cyclospora.
- Scrub fruits and vegetables using a produce brush under running water.
- Always wash your hands with soap and water before and after handling raw produce.
- Cut away any damaged areas on fruits and vegetables before eating.
- Refrigerate fruits and vegetables (cooked or fresh) within two hours of preparing it.
Frequently Asked Questions
Is cyclosporiasis life-threatening?
According to the CDC, the infection is generally not life-threatening. However, it is highly unpleasant and can cause severe, lingering gastrointestinal distress that may last for several weeks.
Why are cases higher than reported?
The CDC notes that official counts likely underrepresent the true burden of disease because many people recover without medical intervention and are never tested for the parasite.
How is this different from norovirus?
Dr. Natasha Bagdasarian points out that Cyclospora typically has a longer incubation period than norovirus and is more likely to cause significant cramping and diarrhea rather than the vomiting often associated with norovirus.
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