Detection of circulating Hepatitis B virus immune escape and polymerase mutants among HBV positive patients attending Institut Pasteur de Bangui, Central African Republic

Abstract Background Previous studies in the Central African Republic (CAR) reported the presence of recombinant genotype E/D and suspicion of Immune Escape Mutants (IEMs) without further investigation on the impact of the mutants on the prevention, diagnosis, and treatment measures in place. Consequently, this study investigated HBV IEMs and drug resistance among HBsAg positive patients attending Institut Pasteur de Bangui in the CAR. Methods A total of 118 HBsAg positive patient’s sera having any HBV antecedent about treatment or vaccination record at the Institut Pasteur de Bagui, were sampled between 2017-2019. Subsequently, the spanning surface and polymerase gene of HBV were amplified by PCR and sequenced. Isolated HBV were genotyped/subgenotype by phylogenetic and serotyped based on amino acid residues at position s122, s127, s140, s159, and s160, then analyzed for HBV IEMs and drug resistances. Results Spanning surface and polymerase genes were successfully amplified and sequenced in 51 samples. Isolated HBV were accounted for 49 genotypes E and 2 subgenotypes A1, serotyped respectively ayw4 and ayw1. Potentials IEMs sY100C, sA128 V, sM133 T, and several polymerase mutants were identified. Conclusion This study raises the awareness of further studies to be conducted on a large scale to understand more about HBV IEMs and drug resistance in the CAR.