Genotypic variability and the mutational landscape of the hepatitis B virus among HIV‑infected patients living in the regions of Western Siberia (Russia)

Abstract Background. Hepatitis B is a major public health problem due to its prevalence, complications, and genetic variability, which requires detailed molecular characterization for effective treatment. HIV‑HBV co‑infection exacerbates the course of hepatitis B, increases the risk of liver damage and death, and also reduces the effectiveness of antiviral therapy. The genetic diversity of the hepatitis B virus in HIV‑positive individuals has not been sufficiently studied, so such research is extremely important for developing more effective control and treatment strategies. Materials and methods. The study analyzed 708 blood serum samples were collected from patients with confirmed HIV infection. For primary screening for HBV DNA, a commercial "AmpliSens HBV-FL" kit was used. For the selected positive samples, next-generation sequencing on the Illumina MiSeq platform was used to obtain full-genomic HBV nucleotide sequences, which were serotyped, genotyped, and analyzed for the presence of clinically significant mutations Objective. To identify and characterize the variants of hepatitis B in HIV‑infected patients from three geographically close regions of Western Siberia (Novosibirsk Region, Tomsk Region, and the Altai Republic). Results. The incidence of HBV genetic material in the study group was 8.5% (95% CI = 6.6–10.8). The work analyzed 60 full-genomic sequences of the identified HBV variants. All studied HBV variants were assigned to genotype D, and the distribution of HBV subgenotypes in the regions was different and consistent with previously obtained data. The overall detection rate of mutations in the hepatitis B virus surface antigen (S gene) was 55.0%, BCP mutations – 28.3%, PreCore mutations – 66.7%, mutations in the Core and X genes were detected in each of the 60 analyzed genome-wide sequences of HBV variants. Conclusion. The results highlight the importance of continuous molecular monitoring for the development of diagnostic strategies, improving the effectiveness of vaccination, and clinical management of HBV patients, especially among people living with HIV.