ISOLATION OF CRYPTOSPORIDIUM-PARVUM AND CYCLOSPORA-CAYETANENSIS FROM VEGETABLES COLLECTED IN MARKETS OF AN ENDEMIC REGION IN PERU

Cryptosporidium parvum and Cyclospora cayetanensis are protozoan patho gens that cause prolonged diarrhea in both immunocompetent and immunoc ompromised hosts. Cryptosporidium parvum can be transmitted via the fe cal-oral route, while the exact mechanisms cf transmission of Cyclospo ra cayetanensis have not been fully determined. Humans appear to be th e sole host for the latter and a distinct seasonality has been observe d in endemic areas around the world. Samples of vegetables were collec ted at several small markets in a periurban slum in Peru during the se asons of high and low incidence. The vegetables were washed, the super natants were collected and centrifuged, and the pellets were resuspend ed in a solution of 2.5% potassium dichromate. Pellets were examined u sing direct microscopic observation, acid-fast staining, and immunoflu orescent assays for C. parvum and Cyclospora cayetanensis oocysts. Sam ples were collected during three time periods: the season of low incid ence, the beginning of the season of high incidence, and end of the se ason of high incidence. Of the total vegetables examined, 14.5% contai ned C. parvum oocysts and 1.8% had Cyclospora oocysts. Thus, market ve getables may provide a route by which Cryptosporidium and Cyclospora c an be transmitted. Our study also suggests that washing vegetables doe s not completely remove Cryptosporidium and Cyclospora oocysts.