A Model for the Transmission of Dengue

In this paper, we formulate a dengue model to explore the complex dynamics induced by antibody-dependent enhancement (ADE). The basic reproduction number Ro is calculated. We analyze the regions of existence and stability for the steady state solutions. Numerical simulation manifests that backward bifurcation may occur and there may be a stable endemic equilibrium even if the basic reproduction number is below 1, which implies that the basic reproduction number is not enough to describe whether dengue will prevail or not. We should pay more attention to the initial states.