Abstract:

In this article, an SIRS epidemic model spread by vectors (mosquitoes) which have an incubation time to become infectious is formulated. It is shown that a disease-free equilibrium point is globally stable if no endemic equilibrium point exists. Further, the endemic equilibrium point (if it exists) is globally stable
with a respect ``weak delay". Some known results are generalized.

Key words: SIRS epidemic model, time delay, global asymptotic stability, lyapunov functional