Periodic solutions of seasonal epidemiological models with information‐dependent vaccination.

In this paper, we study nontrivial periodic solutions for seasonal epidemiological models with information‐dependent vaccination. Using Leray–Schauder degree theory, we establish new results concerning the existence of at least one nontrivial periodic solution for the SIS$$ SIS $$ and SIR$$ SIR $$ models with seasonality, state‐dependent vaccination coverage and delayed information. Some numerical simulations are presented to illustrate the effect of such vaccination coverage. [ABSTRACT FROM AUTHOR]