Amino acid substitutions in core and HBsAg regions of hepatitis B virus in patients with monoinfection and HBV/HIV-coinfection in the Republic of Guinea

S Boumbaly,A A Totolian,A V Semenov,E В Zueva,Yu V Ostankova,Th A L Balde,A N Schemelev,E Serikova,D Е Valutite

doi:10.22328/2077-9828-2021-13-3-96-107

Abstract

The aim of this study was to characterize the genetic variants of HBV currently circulating in the Republic of Guinea, based on the nucleotide sequences of the complete virus genome, and to analyze clinically significant mutations in the Core and HBsAg regions during HBV monoinfection and HBV/HIV coinfection.Materials and methods. The study material was represented by 2616 blood serum samples collected from residents of the Republic of Guinea. The subjects were examined for the presence of HBV markers with a qualitative detection of HBsAg, HBs IgG, and HBCore IgG. HBV complete genome nucleotide sequences were obtained for 298 samples including HIV/HBV coinfected patients. Amplification and subsequent sequencing of HBV were performed using nested PCR with pair’s overlapping primers jointly flanking the complete HBV genome (S, P, C, X genes).Results. HBV serological markers were detected in 80.77% samples, while HBsAg was detected in 16.01% of the examined group. HBV DNA we detected in 22.36%. The prevalence of HBsAg-negative HBV in patients with HIV RNA is 45.16%, which is significantly higher than 6.07% found in the group without HIV infection. Phylogenetic analysis of HBV in the examined samples showed that HBV genotype E (75.5%) predominates in the group compared to HBV genotype D1 (9.39%), D2 (4.02%), D3 (6.37%), and A2 (4.7%). In the tested group, the variability of amino acids among the HBV samples was higher in the PreCore/Core region than in the PreS1/PreS2/S region. SHB mutations were detected in 83,89%, Core mutations in 94.29%, PreCore amino acid substitutions in 16.77% of the patients, respectively.The results obtained in this work demonstrate a high prevalence of HBV in the region and indicate the need for further largescale studies of HBV mutations in order to improve strategies for disease control and prevention in the Republic of Guinea.

Highlights

Hepatitis B virus (HBV) is one of the most common hepatotropic viruses which can cause both acute and chronic liver diseases
The results obtained in this work demonstrate a high prevalence of HBV in the region and indicate the need for further largescale studies of HBV mutations in order to improve strategies for disease control and prevention in the Republic of Guinea
We examined 2616 clinical blood serum samples; HBV serological markers were detected in 2113 samples, or 80.77%, while HBV surface antigen (HBsAg) was detected in 16.01% of the examined group

Summary

Introduction

Hepatitis B virus (HBV) is one of the most common hepatotropic viruses which can cause both acute and chronic liver diseases. HBV infection is prevalent in the African continent; the number of people in Africa with CHB is over 75 million, 25% of whom will presumably die from liver disorders. In East and South Africa, the HBsAg prevalence is relatively low and corresponds to the average level [1], whereas in such North African countries as Tunisia, Algeria, Egypt, and Morocco, the level is below 2% [4]. This can partially be explained by differences in risk factors and transmission routes in different countries. The prevalence estimates at the country level indicate a high infection burden in sub-Saharan Africa [1]

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