Cyclospora Outbreak 2026: 17,000+ US Cases Linked to Iceberg Lettuce — What You Need to Know

The cyclospora outbreak of 2026 has become one of the largest foodborne illness outbreaks in recent US history, with more than 17,000 laboratory-confirmed cases reported since May — a roughly 15-fold jump compared with the same period last year. Health officials at the CDC and FDA have traced a major multistate cluster to processed iceberg lettuce sourced from central Mexico, and investigators are warning that the true number of people sickened is likely far higher than reported.

Here is what you need to know about the outbreak, the parasite behind it, and how to protect yourself and your family.

What is happening: cyclospora cases are surging across the US

According to the Centers for Disease Control and Prevention (CDC), 17,180 laboratory-confirmed cases of cyclosporiasis acquired in the United States were reported between May 1 and August 24, 2026. For comparison, only 1,180 cases were reported during the same window in 2025. The CDC is also aware of at least 11,844 additional cases that are not yet laboratory-confirmed or still require investigation.

The surge is being driven in large part by a multistate outbreak linked to processed iceberg lettuce from central Mexico, processed by Taylor Farms de Mexico and sold under various brands and foodservice labels — including lettuce served at Taco Bell locations.

Key outbreak numbers as of the CDC’s latest update (August 27, 2026):

• 11,458 illnesses linked to the iceberg lettuce outbreak
• 20 states involved, including newly added Georgia, Tennessee, and Texas
• At least 495 hospitalizations
• 2 deaths, both reported in Michigan
• Illnesses began as early as June 14, with onset dates continuing through mid-August

In addition to the lettuce outbreak, the CDC and FDA are investigating at least six other clusters for which sources have not yet been confirmed.

The source: recalled iceberg lettuce from central Mexico

On July 17, 2026, Taylor Farms de Mexico recalled all iceberg lettuces sourced from central Mexico after epidemiologic and traceback data showed the lettuce was contaminated with Cyclospora and making people sick. Most illnesses in the outbreak began before the recall.

The good news for shoppers: the best-by dates on the recalled products have now passed, and the lettuce should no longer be available in stores or restaurants. Public health investigators are using Cyclospora genotyping — a technique that groups genetically related parasites — to confirm that illnesses in the outbreak share a common source.

What is cyclospora?

Cyclospora cayetanensis is a microscopic, single-celled parasite that infects the small intestine and causes an intestinal illness called cyclosporiasis. People become infected by eating food or drinking water contaminated with human feces containing the parasite. It is not spread directly from person to person.

Cyclosporiasis is seasonal in the United States, with most cases occurring between May and August. Outbreaks have historically been linked to fresh produce such as raspberries, basil, cilantro, and — as in this outbreak — lettuce. The parasite is commonly found in tropical and subtropical regions, and travelers to those areas face a higher risk.

Symptoms to watch for

Symptoms typically begin about one week after exposure (anywhere from 2 days to 2 weeks or more) and can include:

• Watery, frequent — and sometimes explosive — diarrhea
• Loss of appetite and weight loss
• Abdominal cramping and bloating
• Increased gas and nausea
• Fatigue and low-grade fever

Without treatment, the illness can last from a few days to more than a month. Symptoms may also seem to go away and then return one or more times (relapse). Some infected people never develop symptoms at all.

Diagnosis and treatment

If you have persistent watery diarrhea, see your healthcare provider and mention the possibility of cyclosporiasis. The infection is diagnosed with a stool sample, but standard lab tests often miss Cyclospora — your doctor must specifically request testing for the parasite, and you may need to provide several samples on different days.

Cyclosporiasis is treated with the antibiotic trimethoprim-sulfamethoxazole (sold as Bactrim, Septra, or Cotrim). If you are allergic to sulfa drugs, ask your doctor about other options. Resting and drinking plenty of fluids is also important while you recover.

Most people with healthy immune systems recover even without treatment, but people in poor health or with weakened immune systems face a higher risk of severe or prolonged illness.

How to protect yourself

There is no vaccine for cyclospora, but you can reduce your risk with good food-safety habits:

• Wash all fresh produce thoroughly under running water before eating, cutting, or cooking — even if you plan to peel it
• Scrub firm produce (like melons and cucumbers) with a clean brush
• Cook food to safe temperatures and keep raw and cooked foods separate
• Drink safe, treated water, especially when traveling
• Wash your hands with soap and water after using the bathroom, changing diapers, and before handling food
• Check the FDA recall list if you have store-bought or restaurant lettuce and are concerned

Long-term concern: post-infectious IBS

Beyond the acute illness, doctors are watching for a possible wave of post-infectious irritable bowel syndrome (PI-IBS). Foodborne infections are a known trigger for long-lasting gut symptoms, and experts have warned that this summer’s massive cyclospora outbreak could lead to a surge in new IBS cases.

In 2023, Wisconsin physicians published what is believed to be the first documented case of IBS following cyclospora infection — a 65-year-old woman who had loose stools, urgency, and abdominal cramping more than eight months after her initial illness. Researchers are now investigating whether this outbreak will produce a similar pattern.

Frequently Asked Questions

What food is linked to the 2026 cyclospora outbreak?

The CDC and FDA linked the largest cluster to processed iceberg lettuce sourced from central Mexico and processed by Taylor Farms de Mexico, including lettuce served at Taco Bell. The company recalled all central Mexico-sourced iceberg lettuce on July 17, 2026, and the recalled products’ best-by dates have passed.

How many people have gotten sick?

At least 11,458 illnesses in 20 states are tied to the lettuce outbreak, with 495 hospitalizations and two deaths. Overall, more than 17,180 laboratory-confirmed US-acquired cyclosporiasis cases have been reported since May 1, 2026.

Is cyclospora contagious from person to person?

No. The parasite needs 1–2 weeks in the environment to become infectious after passing in a bowel movement, so direct person-to-person spread is unlikely. Infection occurs by consuming contaminated food or water.

How long does cyclospora last?

Untreated, the illness can last from a few days to more than a month, and symptoms can relapse. Treatment with trimethoprim-sulfamethoxazole (Bactrim) typically shortens the illness.

Should I stop eating lettuce?

The recalled products are no longer on shelves, and CDC does not currently advise avoiding all lettuce. However, always wash fresh produce thoroughly and follow safe food-handling practices. If you develop watery diarrhea lasting more than a few days, contact your healthcare provider and ask about cyclospora testing.

Bottom line

The 2026 cyclospora outbreak is a stark reminder that foodborne illness can strike at scale — and that thorough washing, safe food handling, and prompt medical attention for persistent diarrhea are simple defenses that work. If you have symptoms, don’t wait: ask your doctor specifically about cyclospora testing, because routine stool tests can miss the parasite.

Sources: CDC Cyclosporiasis Case Data (updated August 25, 2026), CDC Investigation Update (August 27, 2026), CDC About Cyclosporiasis (updated August 21, 2026), FDA Outbreak Investigation, The New York Times (August 31, 2026), CIDRAP.