TURK 2025

Chronic Hepatitis B Virus (HBV) infection remains a major global health concern, particularly due to its progression to liver-related complications such as cirrhosis and hepatocellular carcinoma. In this study, we present a compartmental transmission model that captures the dynamics of chronic HBV infection by incorporating key biological and clinical factors, including antiviral treatment, vaccination, and natural immunity. The population is structured into four compartments: susceptible, infected, chronic, and recovered individuals. The model accounts for disease transmission, progression from acute to chronic infection, vaccination effects, recovery due to immune response, and mortality due to both natural causes and infection. We determine Disease-Free Equilibrium (DFE) and Endemic Equilibrium (EE) and examine their stability under different epidemiological conditions. Through mathematical analysis, we explore the dynamical behavior of the system and derive the role of antiviral treatment and immune response in reducing the burden of chronic infection. Preliminary results suggest that enhancing both treatment and natural immunity significantly contributes to lowering the chronic HBV prevalence. Finally, numerical simulations are conducted to illustrate the impact of varying treatment and immunity parameters on the long-term dynamics of the disease. This model provides a framework for evaluating public health interventions and guiding policy decisions in HBV control strategies.