“…Figure 2 represents the flow of individuals into the different compartments and it has been constructed with these assumptions: recruitment is by births only, a variable population, a constant mortality rate, no permanent immunity to tuberculosis, no immediate infectivity. Parameters: λ , recruitment by births, β , force of infection, µ , death rate of humans, α , disease induced deaths in humans due to active tuberculosis, 1 α , disease induced deaths in humans due to MDR tuberculosis, γ , recovery rate of infected humans from active tuberculosis, δ , recovery rate of infected humans from MDR tuberculosis, h λ , , rate at which the exposed become infectious, σ , rate at which the infected with active tuberculosis become resistant ρ , rate at which recovered humans become susceptible.…”