[An outbreak of Cyclospora cayetanensis in Medellín, Colombia].

Objective: Describing an outbreak of gastrointestinal disease in a group of 56 patients from Medellín, Colombia.

Methods: An unusual number of cases of diarrhoea appeared in April 2002 and 56 samples of stool from the same number of individuals were collected because a patient proved Cyclospora cayetanensis positive. A clinical-epidemiological survey, direct coprology, formol-ether concentration and modified Zielhs Neelsen staining were then carried out.