An SIS disease transmission model with recruitment-birth-death demographics

The SIS epidemiological model studied here has a general population-size-dependent disease incidence, recruitment, exponential births and deaths, disease-related deaths, disease-reduced reproduction, and vertical transmission. Explicit threshold parameters and global asymptotic stability results are obtained. The population dynamics are affected by the presence of the disease combined with disease-related deaths and reduced reproduction of infectives. The population size can decrease to a new size below its carrying capacity or the exponential growth rate constant of the population can be reduced.