Cryptosporidium species are minute, coccidian protozoan parasites that have been associated withenterocolitis. It has worldwide distribution and has emerged as an important cause of diarrhea,particularly in children less than 5 years of age and in immunocompromised individuals. Waterbornetransmission is particularly troublesome because Cryptosporidium parvum oocysts are not eliminatedby chlorination or domestic disinfectants. In the present study, single stool specimens from youngchildren (< 5 years) presented with diarrhea were collected in Khyber teaching hospital, Peshawar,Pakistan. Wet mount preparation and modified Ziehl-Neelsen staining were used for identification ofoocysts in stool specimens. Cryptosporidium oocysts were found in 18 (9.0%) out of 200 childrensuffering from diarrhea. Infection was common in children between 1 - 24 months of age and associatedwith abdominal cramps (50%), vomiting (61.1%) and prolonged duration of diarrhea (88.9%). Direct andindirect contact with animals was present in most of C. parvum infected children (83.3%). Most of C.parvum infected children were consumers of well water (77.8%). Cryptosporidium spp. are highlyinfectious causes of diarrheal illness around the world. It is an important cause of diarrhea in children.Clinician and laboratories should be encouraged to include C. parvum diagnostic techniques whiledealing with diarrheal stool samples of young children
