Cyclospora cayetanensis is a newly recognized parasite widely distributed throughout the world, and isolated from children, immunocompetent adults and HIV infected individuals. The clinical manifestations of the infection are watery prolonged diarrhea, anorexia, fatigue, nausea, bloating and weight loss. In immunocompetent individuals, diarrhea is usually self limited but may last several weeks. In immunocompromised hosts it is prolonged, severe and can be associated with biliary tract involvement. We report a 50 years old female that, five days after returning from Cuba, presented with low grade fever; anorexia, fatigue, explosive diarrhea and weight loss. Physical examination was normal. A stool specimen contained many organisms with morphological features of Cyclospora caetanensis. The diagnosis was confirmed at the Centers for Disease Control (Atlanta Ga).