Serological and molecular characterization of Cryptosporidium species from humans in Sokoto State, Nigeria

Cryptosporidium species are one of the most common causes of gastrointestinal infection in humans around the world. This study aimed at the characterization of Cryptosporidium species in humans using the 18S rRNA gene. Among the 368 human faecal samples screened using Cryptosporidium antigen Copro-ELISA kit, 61 (16.6%) were positive. The positive faecal samples were subjected to Nested PCR for the amplification of 830 bp fragments of small subunit (SSU) rRNA gene and followed by nucleotide sequencing. Out of the 61 copro-ELISA positive samples, 5 (8.2%) were PCR positive for Cryptosporidium species (3 (4.9%) of C. parvum and 2 (3.3%) of C. hominis). Two HIV patients were found to be harbouring C. parvum and C. hominis, so also as hypertensive and diarrheic patients harbouring C. parvum and C. hominis, respectively. Higher prevalence rates of Cryptosporidium was found in young children (11.1%), males (8.7%), loose faeces (42.9%) than older age groups (8.7%), females (7.9%) and well-formed (3.1%) or mucoid/pasty faeces (0%) based on the data gathered from the close-ended questionnaire also used on each human subject. This study was the first to report C. parvum and C. hominis infecting humans in Sokoto state, Northwestern Nigeria. It is suggested that a multi-locus study of Cryptosporidium species in developing countries would be necessary to determine the extent of transmission of Cryptosporidium in the populations.