In the United States, 190 cases of a rare parasite-caused foodborne illness have been reported since May — and 145 of them involve people who had not travelled abroad. The source of contamination remains unknown, and the outbreak is spreading across 17 states as the Fourth of July nears.
What You Will Learn
- What cyclospora infection is, how it spreads, and why its appearance in the United States without international travel concerns health authorities
- What the symptoms are — and why they can linger for more than a month without treatment
- Which precautions to take to prevent this infection, especially when traveling in the summer
A Rare Infection That Signals an Unusual Season
Cyclospora is an intestinal infection caused by parasites of the Cyclospora genus, contracted by consuming food or water contaminated with fecal material. Historically, it primarily affected travelers returning from Central and South America, Southeast Asia, the Middle East, or Africa. Its widespread presence in the United States without a link to foreign travel is unusually concerning.
From early May to mid-June, 190 cases have been reported to U.S. health authorities. Of these, 145 involve individuals who had not left the United States in the two weeks prior to infection. Since the infection does not spread directly from person to person, the evidence points to a contaminated domestic food or water source.
17 States Affected, Source Unknown
The 145 American-origin cases are spread across 17 states. New York accounts for between 31 and 80 cases according to the latest CDC figures. While the East Coast is particularly affected, cases have also been reported as far as Texas, Colorado, and Alaska.
The CDC notes that there is currently no evidence of a single outbreak linking all these cases — several distinct clusters appear to exist simultaneously across multiple states. Local, state, and federal health authorities — the CDC and FDA — are continuing investigations to identify potential sources. No deaths have been reported among the 20 people hospitalized in the confirmed cases.
Symptoms That Can Last More Than a Month
Initial symptoms typically appear about a week after infection. The hallmark is watery diarrhea — sometimes explosive — accompanied by cramps, bloating, loss of appetite, nausea, and fatigue. Headache, mild fever, body aches, and vomiting can also occur in more severe cases.
Without treatment, symptoms can last a few days — or persist for more than a month. The standard treatment relies on antibiotics, though some cases resolve on their own, which likely explains why the 190 reported cases underestimate the true number of infections.
Summer Precautions
The “cyclosporiasis season” typically runs from early May through late August, aligning with the peak travel period. To protect yourself: wash your hands regularly, favor bottled water and sealed pasteurized products when traveling in at-risk regions, and make sure foods are thoroughly cooked. If you experience suspicious symptoms, note what you ate and consult a doctor.
