Cyclospora outbreak: The parasite behind 'explosive diarrhea' cases 

Medically reviewed by Dr. Betsy Koickel, MD on July 28, 2026.

Key takeaways 

• Explosive diarrhea is a symptom, not a diagnosis. Viruses, bacteria, food intolerances, or parasites, like Cyclospora, can be the underlying cause.
• Cyclospora is a parasite that can cause explosive diarrhea that may last longer than other stomach bugs.
• Seek medical care if diarrhea is persistent, severe, or causing dehydration, especially for high-risk individuals.

The 2026 Cyclospora outbreak: what's happening

Cyclospora is currently making headlines as the FDA and CDC investigate a multistate outbreak linked to fresh produce. 

As of July 16, 2026, the investigation included 1,644 confirmed illnesses across five states, with 94 hospitalizations and no reported deaths. FDA traceback identified Taylor Farms de Mexico as the possible source, prompting a recall of iceberg lettuce from central Mexico.

While this outbreak has drawn national attention, Cyclospora is actually known to be a seasonal illness. Cases typically increase during spring and summer, which may be tied to people eating more produce during the summer months. 

What is explosive diarrhea?

Explosive diarrhea is the sudden passage of forceful, watery stool, often accompanied by urgency, cramping, bloating, or nausea. 

Most cases of explosive diarrhea improve within a few days, but persistent or severe symptoms may require medical attention.

Causes of explosive diarrhea

The causes of explosive diarrhea vary. Because it is a symptom rather than a standalone diagnosis, identifying the underlying trigger is key to proper treatment. The most common sources include infections, foodborne illnesses, and intestinal parasites.

Viral illnesses, such as norovirus or the stomach flu, can cause sudden watery diarrhea, cramping, nausea, and vomiting. Bacterial foodborne infections may lead to similar symptoms, sometimes with fever or more severe abdominal pain. Food intolerances, including lactose intolerance, can also cause urgent diarrhea after eating a specific food.

Other explosive diarrhea causes may include parasites such as Cyclospora, which can lead to prolonged or recurring watery diarrhea rather than a brief stomach bug.

Symptoms of a parasite in the intestines

In addition to sudden, watery stool, symptoms of a parasitic infection include:

• Abdominal cramping and gas
• Loss of appetite and fatigue
• Unintended weight loss or dehydration

The key sign of a parasite versus a typical stomach bug is duration. A viral infection usually resolves in 24-48 hours. A parasitic infection like Cyclosporiasis can linger for weeks or temporarily fade before returning.

How is a foodborne parasite diagnosed?

If your healthcare provider suspects a foodborne parasite, they may order a stool study based on your symptoms and medical history. The provider will determine the best test based on your symptoms and medical history.

Many infections improve with rest and fluids alone and do not require medication. But depending on the cause of the illness and severity, some infections require antibiotics or antiparasitic medications. Your healthcare provider will recommend treatment based on the specific organism identified and your symptoms.

How to help protect the whole family

There are several steps you can take to reduce the risk of stomach parasites or other foodborne illnesses. These include: 

• Cook foods to a safe temperature. Make sure you know the optimal internal temperature for specific foods and use a food thermometer to ensure it reaches that temperature.
• Pay attention to recalls and outbreak alerts. Follow recall guidance and throw the product away.
• Refrigerate cooked food within 2 hours (1 hour if over 90°F) and discard after 3-4 days. 
• Always heat leftovers to at least 165°F using a food thermometer to check. 
• Wash fresh produce before eating it. Rinse fruits and vegetables under running water, even if you plan to peel them. Keep in mind that washing does not remove all parasites.

Freezing food at home is not a reliable way to kill parasites. Standard home freezers generally do not reach temperatures that consistently eliminate all parasites, so freezing should not be used as a food safety strategy. The only way to kill the parasite is to cook all vegetables.

When to visit a provider

Most healthy adults recover well with symptom management, but persistent vomiting, severe diarrhea, or signs of dehydration shouldn't be waited out. People with weakened immune systems, older adults, and young children may be at higher risk for complications and should seek care sooner. 

Urgent care centers are here to help. To get started, find a center near you and walk in or save your spot online.

FAQs

Here are frequently asked questions about the Cyclospora parasite and signs of a stomach parasite. 

Is Cyclospora contagious from person to person?

Not usually. Cyclospora is most often spread by contaminated food or water, not through direct person-to-person contact.

Can kids get Cyclospora?

Yes. Children can become infected with Cyclospora; symptoms are similar to those seen in adults.

Do I need antibiotics if I have Cyclospora?

Not always. Many healthy people recover without treatment, but some people may need prescription medication depending on their symptoms and overall health.

Can Cyclospora go away on its own?

Yes. Many healthy adults recover without medication, although symptoms can last for several weeks and may come and go before fully resolving.

References:

1. https://www.cdc.gov/cyclosporiasis/php/surveillance/index.html
2. https://www.fda.gov/food/outbreaks-foodborne-illness/investigation-5-state-outbreak-cyclospora-illnesses-iceberg-lettuce-july-2026
3. https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/safe-temperature-chart