Mapping Hepatitis B Virus Genotypes, Recombinant Genotypes and Sub- genotypes on the African continent from 1997 to 2021: A Systematic Review with Meta-Analysis

Abstract

Abstract Hepatitis B virus (HBV) has ten genotypes (A-J) based on the divergence of ≥ 8% in the complete genome. These genotype influence disease prognosis, response to therapy and route of viral transmission. This study aimed at mapping the de novo genotype, sub-genotypes as well as genotype mixtures and correlate them with the immigration trends in order to inform future research about the relative distribution of HBV genotypes from a large sample size. A total of 60 full research articles obtained from reputable electronic data bases which included Scopus, PubMed, EMBASE, Willy library, African Journal Online (AJOL) and Google Scholar were analysed for data extraction between February 10th and March 28th 2022. The prevalence of the genotypes, sub-genotypes, recombinant genotypes and I2 statistics for heterogeneity were calculated using MedCalc software version 20.010. The Z-test was used to compare the the relative proportions of the various genotypes by region. The Chi-square test was used for the analysis of the relative prevalence of the emerging genotypes B and C on the African continent by region. In contrast, Fisher’s exact test was used in the analysis of the prevalence of sub-genotypes and genotype mixtures by country. Finally, meta-regression analysis was used for the analysis of the variations in the prevalence of dominant genotype, other genotypes and sub-genotypes/recombinant genotypes over the past 25 years on the continent. Sources of heterogeneity were analysed through meta-regression, and sub-group analysis at 95% CI. A P < 0.05 was considered significant for all analyses. The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO), University of York Centre for Reviews and Dissemination (https://www.crd.york.ac.uk/PROSPERO), under the registration number CRD42022300220 Overall, genotype E had the highest pooled prevalence significantly higher than all the other genotypes (p < 0.001). By region, genotype A posted the highest pooled prevalence in eastern and southern, E in west Africa and D in north Africa (p < 0.0001). Additionally, genotype B was significantly higher in south Africa and C in east Africa (p < 0.0001). A1 and B/E were the most prevalent sub-genotypes and recombinant genotypes respectively (p < 0.0001). Finally, we observed a significant decrease in the prevalence of genotype E in west Africa over the years (p = 0.049) and a significant increase in the prevalence of sub-genotypes/recombinant genotypes over the years in north Africa (p = 0.036). Historical and recent continental and intercontinental migrations can provide a plausible explanation for the HBV genotype, sub-genotype and recombinant genotype distribution pattern on the African continent.