Great question Christina!
From a diagnostic stewardship perspective, the current Cyclospora outbreak should not prompt indiscriminate gastrointestinal (GI) testing of all patients with diarrhea. Rather, it should lead to more targeted, exposure-based testing and appropriate laboratory communication. Although FDA and CDC have now linked a subset of the multistate outbreak to shredded iceberg lettuce served at Taco Bell locations in five states (IN, KY, MI, OH, and WV), most acute diarrheal illnesses remain caused by other pathogens, and laboratory resources should be used judiciously.
Diagnostic stewardship emphasizes targeted testing rather than universal screening. Order Cyclospora-specific testing (or a validated GI molecular panel that includes Cyclospora cayetanensis) for patients with prolonged watery diarrhea and compatible epidemiologic exposures. Routine stool cultures and standard O&P examinations alone may not detect Cyclospora. A thorough food and travel history, combined with close communication with the clinical microbiology laboratory, helps ensure appropriate testing while avoiding unnecessary laboratory utilization.
https://www.cdc.gov/han/php/notices/han00531.html?utm_source=chatgpt.com
Prioritize:
1. Reserve Cyclospora testing for patients with compatible illness and epidemiologic risk.
Consider testing when patients have:
- Prolonged (>3–5 days), profuse watery diarrhea
- Relapsing or persistent gastrointestinal symptoms
- Significant weight loss, fatigue, anorexia, or abdominal cramping
- Recent consumption (within approximately 2 weeks) of fresh produce associated with the outbreak or dining at implicated Taco Bell locations
- Recent travel to endemic areas or other known Cyclospora exposures
- Immunocompromising conditions that increase the risk for prolonged disease
2. Do not rely solely on routine stool ova and parasite (O&P) examinations.
Routine O&P testing may not detect Cyclospora unless specifically requested or unless the laboratory uses methods designed to identify the organism. Laboratories may require:
- A multiplex gastrointestinal PCR panel that includes Cyclospora cayetanensis, or
- Specific Cyclospora PCR testing, or
- Modified acid-fast staining and/or UV fluorescence microscopy when molecular testing is unavailable.
3. Avoid unnecessary broad GI testing.
4. Obtain a careful exposure history before ordering tests.
5. Report confirmed cases promptly.
Cyclosporiasis is a nationally notifiable disease.
Thanks everyone!
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Rodney E. Rohde, PhD, MS, SM(ASCP)CM,SVCM,MBCM, FACSc
Regents' Professor, Texas State University System
University Distinguished Chair & Professor, Medical Laboratory Science [MLS] Program
TEDx Speaker & Global Fellow – Global Citizenship Alliance
Texas State Honorary Professor of International Studies
Associate Director, Translational Health Research Initiative @txst_THR
Past President, Texas Association for CLS
Texas State University
MLS Program, Encino Hall 350B [office ENC 363]
601 University Drive
San Marcos, TX 78666-4616
512-245-3500 [CLS suite]; 512-245-2562 [office]
Email:
rrohde@txstate.eduPronouns: he/him/his
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Original Message:
Sent: 07-17-2026 09:25
From: Christina Nickel
Subject: Cyclospora Outbreak Resources
Dr. Rhode,
Thanks so much for this information. Now that they've determined that the cause is likely the lettuce at Taco Bell (I thought that was a joke, but I digress...) – in terms of diagnostic stewardship, what is your recommendation for guidance on test ordering and/or testing restrictions for our ordering providers?
Thanks in advance!
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