Prevalence and Molecular Characterization of Dral 1 gene of Schistosoma haematobium Associated with Pathogenesis of Human Urinary Schistosomiasis among School Pupils in Cross River State, Nigeria

Abstract

Urinary schistosomiasis which is transmitted by schistosome species is the major cause of liver and bladder pathologies and still remains a serious threat in the underdeveloped and developing world. This study evaluates the prevalence of Schistosoma haematobiuminfection  among school aged children in Biase, Obubra and Ogoja Local Government Areas of Cross River State. Five hundred (500) pupils were examined and selected randomly from a public primary and secondary schools in the study area. Freshly passed mid-day urine samples were collected and transferred to the laboratory where there were examined for the presence of Schistosoma haematobium eggs. Study participants were grouped into three age groups,8-10 years. 11-13 years, and 14-16 years old. Overall prevalence of S. heamatobium was (13.6%). Infection was more prevalent among the age group of 14-16years, the percentage of prevalence and intensity of infection were higher in males (14.1%) than in females (6.9%). Inter simple sequence repeats of PCR test performed for the collected urine samples using ISSR test of the Dral-1 gene reveals 73% study subjects had a polymorphism for UPA02 and UPA13 primers, while primer UPA13 showed 24% polymorphism. Total number of polymorphic bands were 2 each for primers UPA02 and UPA13 primers while UPA12 showed only one polymorphic band. Major allele frequencies (MAF) were 0.53 for each of UPA02 and UPA 13 primers but showed 0.71 frequency with UPA12 primer. Allele frequencies (AF) also varied slightly among the primers used. UPA02 and UPA 13 had allele frequencies of 8 each while UPA12 had 4 allele frequencies (Table 13). Nei’s genetic diversity indices for the primers revealed variations among the different primers. UPA02 and UPA13 Nei’s gene diversity of 0.64 each while primer UPA12 showed gene diversity of 0.28. Results of polymorphic information content showed that primers UPA02 and UPA13 discriminately revealed a PIC of 0.68 while UPA12 discriminated 0.28 PIC. This study therefore, revealed a critical need for targeting health campaign towards school age children and heads of households in order to empower them with the basic knowledge to recognize, treat and manage their health challenges.Applications of one to two doses of praziquantel considerably reduced the severity of urinary Schistosomiasis in the study area.