Modeling the effect of tobacco smoking on the in-host dynamics of HIV/AIDS

In this paper, a simple model for the effect of tobacco smoking in the in-host dynamics of HIV is formulated with the aim of studying how tobacco smoking affects HIV in-host dynamics. The basic reproduction number here known as smoking induced reproduction number R0is computed, disease free and endemic equilibria are derived and conditions for their stability are established. Analytical results show that smoking affects both T-cells and Macrophages however, its effects are severe in macrophages than in T-cells. Stability for disease free and endemic equilibria is analyzed. High smoking rate renders disease free equilibrium to be locally and globally unstable. Low smoking rate leads to globally unstable endemic equilibrium. Numerical results reveal that tobacco smoking which confers insensitivity to T-cells and reducing phagocytosis in macrophages can promote in-host HIV dynamics.