Background: Hepatitis B Virus (HBV) remains a major global health challenge, with significant morbidity and mortality associated with chronic infections. Methods: This study examines the epidemiology, screening, and risk factors associated with HBV in Romania, focusing on a comprehensive national screening program, LIVE(RO)2, involving 320,000 individuals (majority of them considered vulnerable population). A questionnaire was used to collect information on the potential risk factors for HBV transmission. Results: The overall prevalence rate of HBV chronic infection among all the participants tested was 1.67% (confidence interval: 1.63–1.72%), with significant differences (p = 0.0001) between participants from the main geographical regions of residence (North-East 1.89%, South 1.38%, South-East 2.06%, and South-West 1.54%). Male persons aged 30–49 or 60–69 years old, from the rural and Eastern parts of Romania and non-Romanian ethnia, with a low level of education, unvaccinated, not married, unemployed, with family members with hepatitis, with personal histories of blood or blood product transfusion, surgical interventions, tattooing, hospitalizations, imprisonment, haemodialysis, unsafe sexual contacts, or with sexual transmitted infectious diseases were risk factors associated with HBsAg seropositivity. Conclusions: Our findings highlight significant demographic and epidemiological patterns of reduced HBV prevalence even in vulnerable persons, as well as modified risk factors and the impact of socio-economic factors.

Background: Hepatitis B (HBV) and Delta (HDV) virus infections pose critical public health challenges, particularly in Romania, where HDV co-infection is underdiagnosed. Methods: This study investigates the epidemiology, risk factors, and clinical outcomes of HBV/HDV co-infection in vulnerable populations, leveraging data from the LIVE(RO2) program. Conducted between July 2021 and November 2023, the program screened 320,000 individuals across 24 counties, targeting socially disadvantaged groups such as rural residents, the Roma community, and those lacking health insurance. Results: Among 6813 hepatitis B surface antigen (HBsAg)-positive individuals, HDV antibody prevalence was 4.87%, with active replication confirmed in 75.6% of HDV-positive cases. Regional disparities emerged, with higher HDV prevalence and replication rates in the Eastern region compared to the South. HDV-positive individuals were more likely to be younger, male, and from rural or socioeconomically disadvantaged backgrounds. Clinically, HDV co-infection correlated with increased liver stiffness, advanced fibrosis stages, and lower steatosis levels compared to HBV mono-infection. Psychiatric comorbidities were more prevalent among HDV-positive patients, highlighting the need for integrated care. Conclusions: This study underscores the urgent need for targeted public health interventions, including enhanced screening, education, and access to novel antiviral therapies like bulevirtide to address the significant burden of HBV/HDV co-infection in Romania.