Dynamical Behavior of a New Epidemiological Model

Figure 3

Taking the initial value (3,1,1) and 𝜏=0, 𝑏=6, 𝛼=𝑑=𝑘=𝑐=𝑢₁=1, and 𝑢₂=2, then 𝑅₀=2>1, and the solution (𝑆(𝑡),𝐼(𝑡),𝐷(𝑡)) tends to the endemic equilibrium 𝐸_∗=(5.0769,0.6923,0.2308) as 𝑡→∞.