Global stability results in a SVIR epidemic model with immunity loss rate depending of the vaccine-age (original) (raw)

In this paper, we formulate a susceptible-vaccinated-infected-recovered (SVIR) model by incorporating the vaccination of newborns, vaccine-age and mortality induced by the disease into the SIR epidemic model. It is assumed that the period of immunity induced by vaccines varies depending on the vaccine-age. Using the direct Lyapunov method with Volterra-type Lyapunov function, we show the global asymptotic stability of the infection-free and endemic steady states. Keyword: Age-dependent epidemic model; Vaccine-age; Waning vaccine-induced immunity; Volterra-type Lyapunov function; Global stability