Detection and Genotypic Characterization of Hepatitis B Virus among Prospective Blood Donors at a Tertiary Healthcare Facility in Central Nigeria

Aims: This study was conducted to detect and type hepatitis B virus circulating among prospective blood donors at a tertiary healthcare Facility in Central Nigeria Study Design: The study was a cross sectional study. Place and Duration of Study: Keffi, Nasarawa State, between January and October, 2018. Methodology: Blood sample (3 ml) was collected from each of the 400 consenting blood donors at Federal Medical Centre, Keffi, Nasarawa State and their socio-demographic information obtained using structured questionnaires. The sera were screened for HBV infection serologic markers (HBsAg, HBsAb, HBeAg, HBeAb and HBcAb) using HBV-5 rapid panel test kit (CTK Biotech. Inc. San Diego, USA). All samples positive for HBsAg, HBeAg and those negative for HBsAg but positive for HBcAb were genotyped by PCR using type-specific primers. Data collected were analysed using Smith’s Statistical Package (version 2.8, California, USA) and P value of ≤ 0.05 was considered statistically significant. Results: Of the 400 blood donors screened, 31(7.8%) were positive for HBsAg, 113(28.3%) for HBsAb, 11(2.8%) for HBeAg, 18(4.5%) for HBeAb and 78(19.5%) for HBcAb. A total of 34 samples (HBsAg-positive and HBsAg-negative but HBcAb-positive) were genotyped and of these, 32 (94.1%) had HBV-DNA bands while the remaining 2(5.9%) samples were not-typable. Furthermore, Of the 32 HBV-DNA-positive samples successfully genotyped, 17(53%) had single HBV genotype infection while the remaining 15 (46.8%) had mixed HBV genotype infection. In relation to frequency of occurrence, single HBV/E genotype was predominant (37.5%), followed HBV/F (9.4%) and HBV/A (6.3%). Meanwhile, double mixed-infection of HBV genotypes B/E had the highest rate (18.8%), followed by B/D (12.5%) and A/B (3.1%). Finally, triple infections with both A/B/D and A/B/E genotypes occurred at the same rate of 6.3% Conclusion: This study reported the circulation of HBV genotypes A, B, D, E and F in the study population with predominance of genotype E and a novel appearance of genotype F in Nigeria. These findings are of public health significance particularly in antiviral therapy.