Abstract
This paper considers two S-DI-A models in random environments. Firstly, using Has'minskii theory of periodic solution, we show that stochastic periodic S-DI-A model has a nontrivial positive periodic solution if
. Then, we construct stochastic Lyapunov functions with regime switching to obtain the existence of ergodic stationary distribution of the solution to S-DI-A model perturbed by white and telephone noises. Finally, examples are introduced to illustrate the results developed.