7/20 Updates:
- The CDC reports that shredded iceberg lettuce served at Taco Bell locations is source of cyclosporiasis infections in five states.
- Dr. Brad Sobolewski (of PEMBlog and PEM Currents Podcast fame) released a new podcast on Cyclospora – check it out for a quick audio rundown of the condition.
If you’ve turned on the news recently, you’ve probably seen headlines about Cyclospora, a parasite responsible for a growing outbreak of cyclosporiasis across the United States.
As of July 14, 2026, the CDC has received reports of 1,645 laboratory-confirmed domestically acquired cases across 34 states, with 141 hospitalizations (9%) and no deaths. Even more striking, the CDC is reviewing more than 5,100 additional reports that still require investigation, meaning the final number of cases will almost certainly continue to rise.
For those of us working in pediatric emergency medicine, though, the more important question isn’t “How big is the outbreak?”
The more important question is:
“Do I need to start thinking about Cyclospora every time a child comes in with diarrhea?”
Probably not – but you should know when to think about it.
Here are three things every PEM clinician should know about cyclosporiasis.
1. Don’t panic – this still isn’t primarily a pediatric disease (and hopefully will never be)
The recent headlines are certainly attention-grabbing, but they’re not telling the whole story.
Although children can develop cyclosporiasis, current data do not suggest that they are driving this outbreak. According to the CDC, patients in the current outbreak range from 2 to 95 years old, with a median age of 44 years.
Pediatric infectious disease experts have been quick to reassure families. Dr. Ian Michelow, the division head of Infectious Diseases and Immunology at Connecticut Children’s, notes that “most children will never get cyclosporiasis,” and even when they do, it is generally treatable. Likewise, Dr. Robert Frenck Jr., chair of the American Academy of Pediatrics Section on Infectious Diseases, emphasizes that most otherwise healthy children recover completely, although symptoms can be prolonged without treatment.
Fortunately, unlike measles or norovirus, Cyclospora is not readily spread from person to person. Infection usually occurs after eating contaminated fresh produce or drinking contaminated water.
2. The child you should worry about isn’t the one with 24 hours of diarrhea
Most children with vomiting and diarrhea still have viral gastroenteritis. Cyclospora should move higher on your differential when the illness doesn’t follow the usual script.
Think about it when a child has:
- Watery diarrhea lasting more than a week
- Symptoms that initially improve, then return
- Persistent fatigue
- Weight loss
- Recent consumption of fresh produce
- Recent travel
- Immunocompromise
Symptoms typically begin about one week after exposure, although onset can occur anywhere from 2 days to 2 weeks later. Without treatment, illness often follows a remitting-relapsing course, lasting weeks – or even months.
3. Know how to test and treat
Cyclospora isn’t difficult to treat. It’s easy to forget to test for it.
Routine stool testing – and even some gastrointestinal PCR panels – may not detect Cyclospora. The CDC specifically recommends requesting Cyclospora testing when clinical suspicion is high because routine ova-and-parasite examinations may miss the organism. PCR-based testing improves detection when available.
For confirmed infection, the CDC recommends trimethoprim-sulfamethoxazole as first-line therapy, generally for 7–10 days in immunocompetent children older than 2 months. Children with immunocompromising conditions may require longer treatment courses.
Fortunately, many otherwise healthy children recover without complications, and supportive care, particularly aggressive attention to hydration – remains an essential part of management.
The Bottom Line
The current Cyclospora outbreak deserves our attention – but not our panic.
For most children with acute diarrhea, viral gastroenteritis remains far more likely.
However, during an active outbreak, Cyclospora deserves a place on your differential when you’re evaluating a child with:
- Persistent watery diarrhea
- Relapsing symptoms
- Weight loss or prolonged fatigue
- Recent produce or travel exposure
- Immunocompromised status
Recognizing the illness early can help avoid unnecessary testing, shorten the duration of symptoms with appropriate treatment, and contribute to public health efforts to identify the source of the outbreak.
Additional Reading:
American Academy of Pediatrics. Cyclosporiasis in Children: Symptoms, Treatment & Prevention.
American Academy of Pediatrics Red Book Online. Cyclosporiasis Outbreak.
Centers for Disease Control and Prevention. Cyclosporiasis Outbreak with Unknown Source.
Nationwide Children’s Hospital. What Parents Need to Know About Cyclosporiasis.
Dr. Joshua Belfer, MD, is a Pediatric Emergency Medicine physician at the Children’s Hospital of Philadelphia, and is the Founder and Editor-in-Chief of HipPEMcrates. He can be reached at HipPEMcrates@gmail.com.
Very topical!!