Threshold dynamics for a tuberculosis model with seasonality.

In this paper, we investigate a SEILR tuberculosis model incorporating the effect of seasonal fluctuation, where the loss of sight class is considered. The basic reproduction number R₀ is defined. It is shown that the disease-free equilibrium is globally asymptotically stable and the disease eventually disappears if R₀ < 1, and there exists at least one positive periodic solution and the disease is uniformly persistent if R₀ > 1. Numerical simulations are provided to illustrate analytical results.