Cyclospora infection is diagnosed by examining stool specimens. Diagnosis can be difficult in part because even patients who are symptomatic might not shed enough oocysts in their stool to be readily detectable by laboratory examinations. Therefore, patients might need to submit several specimens collected on different days. Identification of the parasite requires special laboratory tests that are not routinely done when stool is tested for parasites. Therefore, if indicated, health care providers should specifically request testing for Cyclospora.