prevalence and genetic characterization of cryptosporidium spp. in diarrheic children from gonbad kavoos city, iran

background: cryptosporidium is an intestinal protozean parasite causing water­borne and foodborne outbreaks of diarrheal diseases. the present study was per­formed in order to find prevalence and subtypes of cryptosporidium among children with diarrhea in gonbad kavoos city, northern iran. methods: diarrheic samples were collected from 547 children. the initial parasitologi­cal diagnosis was made based on detection of oocysts using the modi­fied ziehl-neelsen acid-fast staining method. the positive microscopically samples were selected for sequence analysis of partial 60 kda glycoprotein ( gp60 ) gene. results: out of 547 collected samples, 27 (4.94%) were positive for cryptosporid­ium oocysts. fifteen from 27 positive samples successfully amplified in pcr. se­quences analysis of gp60 gene in 15 cryptosporidium isolates revealed that all of them (100%) were c. parvum . the results showed three subtypes of iia subtype family (7 cases) including iiaa16g2r1, iiaa17g1r1, iiaa22g3r1 and one subtype of iid subtype family (8 cases). the most common allele was iid a17g1d (53.3%). conclusion: the predominance of zoonotic subtype families of c. parvum species (iia, iid) in the present study is in concordance with previous studies in iran and emphasizes the significance of zoonotic transmission of cryptosporidiosis in the country.