Cyclosporiasis Outbreak, Indonesia

We describe an outbreak of Cyclospora cayetanensis infection among Dutch participants at a scientific meeting in September 2001 in Bogor, Indonesia.Fifty percent of the investigated participants were positive for C. cayetanensis.To our knowledge, this outbreak is the first caused by C. cayetanensis among susceptible persons in a diseaseendemic area.C yclospora cayetanensis is a newly recognized proto- zoan parasite that causes gastrointestinal illness.C. cayetanensis infection is mostly characterized by a gradual onset of watery diarrhea, sometimes with explosive diarrhea, nausea, and abdominal cramping.Symptoms are often prolonged and can relapse after months (1).Oocysts of C. cayetanensis are, in comparison with those of other coccidian parasites, noninfectious in freshly excreted stool.Therefore, direct person-to-person transmission through fecal exposure is unlikely.Food and water contaminated with sporulated oocysts are the primary modes of transmission (1).Infections have been associated mainly with outbreaks from eating food such as raspberries, salads, and basil (1-3).Infections with C. cayetanensis are seasonal; in the tropics, the wet and cooler seasons provide conditions more favorable for sporulation than do the dry and warmer seasons (1,3).A scientific meeting involving Dutch and Indonesian microbiologists was held September 2-6, 2001, in Indonesia.Immediately after the meeting, several participants reported mild-to-severe gastrointestinal symptoms, and C. cayetanensis infection was diagnosed in 4 participants.We investigated the extent of the outbreak among participants from our institute and identified C. cayetanensis-specific symptoms.