DYNAMICS OF AN SIRS EPIDEMIC MODEL WITH TIME DELAY AND FREE BOUNDARIES

In this paper, an SIRS epidemic model with time delay and free boundaries is studied. At first, we prove the global existence and uniqueness of the solution. And then we obtain criteria for spreading and vanishing. Moreover, the long-time behavior of the solution is given by a spreading-vanishing dichotomy. Finally, the numerical simulations are provided to illustrate our results. Our results indicate that the time delay can slow down the spreading of epidemic.