Cyclosporiasis: What to Know, When to Get Care

Cyclosporiasis is an intestinal illness caused by a microscopic parasite called Cyclospora cayetanensis. People usually become infected by eating fresh produce or drinking water contaminated with the parasite. In the United States, outbreaks are most often linked to imported fresh produce such as berries, leafy greens, cilantro, and basil. Because the infection can drag on for weeks and standard testing often misses it, knowing what to watch for and what to ask your clinician makes a real difference.

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Key Symptoms to Watch For

Symptoms typically begin about one week after exposure to contaminated food, though they can appear anywhere from a couple of days to two weeks or more later. Watch for:

• Watery diarrhea, which can be frequent and at times severe
• Abdominal cramping and bloating
• Nausea and loss of appetite
• Fatigue
• Low-grade fever

A hallmark of Cyclospora is that symptoms often wax and wane. You may feel like you are recovering, only to have the diarrhea and stomach upset return days later. Left untreated, the illness can persist for days to weeks, and sometimes a month or longer, with relapses along the way.

When to Seek Urgent Care

Please seek medical attention if you experience any of the following:

• Signs of dehydration, including decreased urination, dark urine, dizziness, lightheadedness, dry mouth, or excessive thirst
• Inability to keep fluids down because of persistent nausea or vomiting
• Fever greater than 101.3°F (38.5°C) or worsening whole-body symptoms
• Bloody diarrhea
• Significant weight loss or an inability to maintain adequate nutrition

High-Risk Patients Who Should Seek Care Early

Some people are more vulnerable to complications and should consider evaluation even within the first one to two days of symptoms:

• Immunocompromised individuals, including those with HIV/AIDS, organ transplant recipients, and patients receiving immunosuppressive therapy
• Infants and young children
• Older adults
• Pregnant patients

Concerned it's more than a stomach bug?

NextCare clinicians can evaluate your symptoms and order the specialized testing Cyclospora requires. Visit your nearest clinic or reserve your spot online today.

What Every Patient Should Know

Spreading it to your household is unlikely.

Cyclospora is not passed directly from person to person. After the parasite leaves the body, it needs one to two weeks in the environment to mature before it can infect anyone else. That means you generally do not need to isolate from household contacts.

Washing produce is not enough.

Routine rinsing does not reliably remove Cyclospora, which can cling tightly to the surface of fruits and vegetables and resists many standard disinfection methods. Rinsing is still a sensible first step, but it is not a guarantee.

Ask for Cyclospora testing by name.

A routine stool ova and parasite (O&P) test does not automatically detect Cyclospora because the parasite stains poorly with standard methods. Specific testing, such as PCR or modified acid-fast staining, must be requested. If you suspect Cyclospora, tell your clinician directly so the right test is ordered.

Testing can be specialized and costly.

Because it requires special techniques, Cyclospora testing may be expensive, and insurance coverage can be limited unless you have symptoms and testing is clinically indicated.

The right treatment works quickly.

Cyclosporiasis is treated with the antibiotic trimethoprim-sulfamethoxazole (TMP-SMX), usually for 7 to 10 days. Patients often notice symptom improvement within one to two days of starting treatment, which is exactly why early medical evaluation is so valuable.

The Bottom Line

If you have persistent watery diarrhea after eating fresh produce, do not wait it out, especially if you fall into a high-risk group. Cyclosporiasis is very treatable once it is correctly identified, but it is easy to miss without the right test. Come see us at NextCare, describe your symptoms and any recent foods consumed, and ask specifically about Cyclospora so we can get you the right care quickly.

Sources

CDC: About Cyclosporiasis

CDC: Clinical Overview of Cyclosporiasis

CDC: Clinical Care of Cyclosporiasis

CDC: Preventing Cyclosporiasis

CDC Health Alert: Domestically Acquired Cyclosporiasis Cases, 2026

FDA: Cyclospora

This article is for general education and is not a substitute for professional medical advice. If you are concerned about your symptoms, contact NextCare or your healthcare clinician.

The NextCare Clinical Advisory Team is dedicated to ensuring our health information is accurate, current, and aligned with evidence-based medical practices. Our team of experienced healthcare professionals reviews educational content for clinical accuracy, helping provide patients with trusted information to support informed healthcare decisions. While our content is intended for educational purposes, it should not replace personalized medical advice from a qualified healthcare clinician.