Cyclosporiasis

Cyclosporiasis Situational Awareness Update

The CDC is tracking illnesses across 45 states, with the Food and Drug Administration (FDA) investigating multiple distinct outbreak clusters that include an outbreak tied to shredded iceberg lettuce.

Epidemiologic and traceback investigations have linked a portion of illnesses in the outbreak to recalled shredded iceberg lettuce supplied by Taylor Farms de Mexico. While this product has been identified in the national outbreak, public health officials continue to investigate additional cases, and not every reported illness is necessarily linked to the recalled product.

In suburban Cook County, reported cases have exceeded the number typically seen at this point in the summer, indicating elevated local activity. Disease investigators continue to interview patients, review food exposure histories, and work with state and federal partners to determine whether cases are associated with the multistate outbreak or other potential sources of exposure.

Cyclosporiasis Case Counts in suburban Cook County (as of July 28, 2026)

• 93 Confirmed / Probable cases

CCDPH continues to monitor the situation closely and will provide updates as additional information becomes available.

For statewide case counts and updates, visit the Illinois Department of Public Health (IDPH) .

For national surveillance data and information about the multistate outbreak, visit the CDC Cyclosporiasis Surveillance and CDC Outbreak Investigation webpages.

About Cyclosporiasis

Cyclosporiasis is an infectious disease caused by a parasite called Cyclospora. Most people infected with Cyclospora develop watery diarrhea, stomach cramping, bloating or increased gas, fatigue, and nausea. Symptoms typically start around seven days after ingesting the parasite. Sometimes people infected with Cyclospora will have no symptoms at all.

• Cyclosporiasis, an infectious disease caused by a parasite that infects the small intestine.
• Cyclosporiasis is not a virus and doesn’t spread person to person.
• People become infected by consuming food or water contaminated with particles of feces from an infected person. It is spread through contaminated food or water and can get into produce if it’s grown in soil or washed with water contaminated with feces; fresh fruits and vegetables are common culprits.
• Previous outbreaks have included fruits and vegetables such as raspberries, snow peas, mesclun lettuce, basil, and cilantro.
• Consumers should wash fresh fruits and vegetables thoroughly, follow food safety practices, and contact a healthcare provider if you develop symptoms such as prolonged diarrhea after eating fresh produce.

Symptoms

• You may develop symptoms anywhere from 2 days to 2 weeks after exposure.
• Watery diarrhea, sometimes frequent and severe often referred to as “Explosive Diarrhea”.
• Appetite loss, cramping, bloating, nausea, low-grade fever.
• Don’t ignore your symptoms – If untreated, the illness may last for a few days to a month or longer and may follow a remitting-relapsing course.
• Although cyclosporiasis usually is not life threatening, reported complications have included malabsorption, cholecystitis, and reactive arthritis.

Treatment

• Cyclosporiasis is treatable with antibiotics. Anyone with symptoms should see a healthcare provider rather than wait it out.
• Most people with cyclosporiasis typically feel better within 1 to 2 weeks, but some symptoms like diarrhea can relapse or last up to a month or longer.
• People with healthy immune systems can recover with extra fluids and rest. Others may need an antibiotic, such as trimethoprim-sulfamethoxazole (Bactrim), prescribed by their healthcare provider.

What to do if you have symptoms

• Any symptoms should be monitored closely and reported to a healthcare provider.

Prevention Tips

Washing hands

• Wash hands with soap and water before and after handling or preparing raw fruits and vegetables.

Preparing food

• Wash all fruits and vegetables thoroughly under running water before eating, cutting, or cooking.
• It is important to thoroughly wash produce even if it is labeled as pre-washed.
• Scrub firm fruits and vegetables, such as melons and cucumbers, with a clean produce brush.
• Cut away any damaged or bruised areas on fruits and vegetables before preparing and eating.
• Cooking can kill the parasite. Since washing alone cannot guarantee the parasite’s removal, cook produce to a temperature of at least 158 °F (70°C) .

Storing food

• Refrigerate cut, peeled, or cooked fruits and vegetables as soon as possible (within two hours).

How Public Health Helps Investigate Foodborne Illness

When someone is diagnosed with cyclosporiasis, public health begins an investigation to help identify where the illness may have come from and whether other people may be at risk.

• We track cases across suburban Cook County to identify patterns and trends.
• We contact people who became sick to learn what they ate, where they shopped, and other details that may help identify a common source.
• We work closely with the Illinois Department of Public Health and the Centers for Disease Control and Prevention (CDC) to compare information across Illinois and the country.
• We share timely guidance with residents, healthcare providers, and community partners to help prevent additional illnesses.

If we call you, please answer

If you are diagnosed with cyclosporiasis, someone from Cook County Department of Public Health may call you. We will ask questions about where you’ve eaten, grocery stores you’ve visited, and foods you may have consumed in the weeks before you became sick. If we call you, please answer. Every interview is an important piece of the puzzle.

Your answers are confidential and can help investigators identify contaminated food more quickly, protect others from getting sick, and stop additional illnesses.