Global attractivity and permanence of a delayed SVEIR epidemicmodel with pulse vaccination and saturation incidence

摘要

In this study, we formulate and analyze a new SVEIR epidemic disease model with timedelay and saturation incidence, and analyze the dynamic behavior of the model underpulse vaccination. Using the discrete dynamical system determined by the stroboscopicmap, we obtain an 'infection-free' periodic solution, further, show that the 'infection-free'periodic solution is globally attractive for some parameters of the model under appropriateconditions. The permanence of the model is investigated analytically. By computer simula-tion it is concluded that a large vaccination rate or a short pulse of vaccination or a longlatent period are each a sufficient condition for the extinction of the disease.