Cyclospora cayetanensis infections in Haiti: A common occurrence in the absence of watery diarrhea

Stool samples from a population-based cohort of mothers and children living in Leogane, Haiti were tested for Cyclospora cayetanensis from January 199 7 through January 1998. Data on gastrointestinal symptoms were also collect ed. During the winter months of January to March, the infection was detecte d in 15-20% of the persons sampled. Most infections did not appear tc, be c ausing diarrhea and most infected persons had few oocysts detectable in con centrates of stool. The infection appears to have marked seasonality, with highest rates during the driest and coolest time of the year. It may be tha t in this tropical setting, high summer temperature is the critical environ mental factor that influences the seasonality of infection. This study demo nstrates that Cyclospora infections in Haiti are common in the general popu lation.