A pulse vaccination SIR model with periodic infection rate β(t) have
been proposed and studied. The basic reproductive number R0 is defined. The
dynamical behaviors of the model are analyzed with the help of persistence,
bifurcation and global stability. It has been shown that the infection-free
periodic solution is globally stable provided R0<1 and is unstable if
R0>1. Standard bifurcation theory have been used to show the existence of
the positive periodic solution for the case of R0→1+. Finally, the
numerical simulations have been performed to show the uniqueness and the global
stability of the positive periodic solution of the system.Comment: 17pages and 3figures, submmission to Mathematical Bioscience