Asymptotic behavior of a nonlinear infection-age-dependentepidemic model

Dynamical behavior of a nonlinear infection-age-dependent SIS epidemic model is studied and the threshold,a basic reproductive number which determines the outcome of the infectious disease is founded.When the basic reproductive number is not greater than 1 meaning the disease will die out,there exists only a disease free equilibrium which is globally asymptotically stable except that the basic reproductive number equals 1.When the basic reproductive number is greater than 1 meaning the disease will persist,there are two equilibria,the disease free equilibrium which is unstable and the endemic equilibrium which is locally asymptotically stable.