Hepatitis-B Virus genotypes among pregnant women in Nasarawa State, Nigeria

Background: Hepatitis B virus (HBV) genotype is a distinct genetic group of the virus strains identified by specific divergence in their genomic sequence. The classification of HBV genotypes indicates that these genotypes do not only influence viral replication dynamics but also impact disease severity and response to antiviral therapy. Understanding the circulating HBV genotypes play critical roles in the virus response to antiviral therapy. This study was conducted to determine the circulating genotype of HBV infection among pregnant women attending antenatal clinic at Primary Health Care facilities in Nasarawa State. Methods: Three hundred and thirty-eight (338) participants were enrolled in this cross-sectional study. Blood samples were collected by venipuncture, processed, and tested using a combo kit with five Sero-markers of hepatitis B virus and the positive samples were characterized using PCR. Results: Using HBsAg as a surrogate of infection, the 28(8.3%) positive samples were analyzed with PCR using type specific primers. Genotypes B and E were identified as coinfection in a sample (0.6%) as the circulating genotype in the study area. The sequence and phylogenetic tree of these genotypes identified in Nasarawa State share a recent common ancestor with samples from Sokoto State, Nigeria. Conclusion: The finding of genotype B and E with a strain diversity within Nigeria lineage in the study area, have critical implications for the epidemiology of hepatitis B virus, vaccination, antiviral therapy and clinical outcomes in Nasarawa State, Nigeria.