Dynamical behaviour of an anti-HBV infection therapy model with time-delayed immune response

Mathematical models have been used to understand the factors that govern infectious disease progression in viral infections. In this paper, based on the standard mass action incidence, an anti-HBV therapy model with time-delayed immune response is set up. The time-delay is used to describe the period of time for antigenic stimulation to generate CTLs. The globally asymptotically stable analysis of the infection-free equilibrium is given in the paper. Some conditions for Hopf bifurcation around endemic equilibrium to occur are also obtained by using the time delay as a bifurcation parameter.