Bloodborne infections in dental practice: prevalence of markers and phylogenetic analysis of circulating strains

INTRODUCTION: Human immunodeficiency virus (HIV) and hepatitis B (HBV) and C (HCV) viruses remain among the most dangerous bloodborne pathogens, posing a significant global public health threat. The aim of our work was to assess the prevalence of HIV, HBV, and HCV markers among dental patients and provide a molecular genetic characterization of the identified pathogens. MATERIALS AND METHODS: We analyzed 497 plasma samples from individuals who sought dental care in St. Petersburg for serological and molecular markers of target infections. Viral genome fragments were sequenced and analyzed when molecular markers were detected. RESULTS: Anti-HCV were detected in 3.8% (19/497) of participants, with HCV RNA in 1% (5/497). HIV Ag/Ab was found in 1.2% (6/497), with two cases (0.4%, 2/497) confirmed by immunoblot; no HIV RNA was detected. HBsAg prevalence was 2.4% (12/497), with anti-HBs in 32.0% (159/497) and anti-HBc in 25.6% (127/497) of participants. Significant age-related trends were observed: anti-HBs predominated in younger groups while anti-HBc was more frequent in older individuals. HBV DNA was detected in 3.8% (19/497) of cases, including 1.8% (9/497) HBsAg-negative infections. Predominant in the Russian Federation viral genotypes were identified (HCV: 1b, 2a, 3a; HBV: D1, D2, D3). One HCV isolate carried mutations associated with resistance to dasabuvir, sofosbuvir, and voxilaprevir. Multiple HBV isolates harbored concurrent mutations causing diagnostic escape (HBsAg-negative variants), reduced vaccine efficacy, viral reactivation, and disease progression. CONCLUSIONS: The study reveals high viral hepatitis prevalence among dental patients. Detection of drug-resistant HCV variants and immune-evading HBV strains underscores the need for enhanced molecular surveillance, improved diagnostic protocols, and strengthened infection control measures.