Molecular characterization of Cryptosporidium isolates from humans in Ethiopia

In this study, 1034 faecal samples from patients with diarrhoea were screened for Cryptosporidium oocysts. Samples were collected from nine different regions in Ethiopia. Of these, 79 samples (7.6%) were positive for Cryptosporidium by modified Ziehl-Neelson staining. From all positive samples DNA was extracted and PCR amplification of the COWP, SSU-rRNA and GP60 gene fragments was performed. A total of 41 samples (52%) were positive in any of the three typing methods. The majority of isolates (39 of 41) was identified as Cryptosporidium parvum, with one Cryptosporidium hominis and one mixed infection. Sequencing of the GP60 gene fragments of 13 isolates resulted in three different subgenotypes of C. parvum, all belonging to the zoonotic subtype family IIa and one subtype of C. hominis (Ib). These data identify C. parvum as the major cause of human cryptosporidiosis in Ethiopia and suggest a zoonotic transmission of the disease in contrast to reports from other developing countries.