Figure 2

Numerical simulations of the solutions for system (17) and the corresponding deterministic system (2), when \(\mathcal {R}_{0}^{s}>1\) with \(\tau_{1}=\tau_{1}^{*}=0.8\) & \(\tau_{2}=0.1<\tau_{2}^{*}\), \(a=0.08\), \(\delta=0.19\), \(\alpha=1.6\), \(c=0.6\), \(K=1\), \(\mu=0.9\), \(r=1\), while the intensities of Brownian motions are relatively small \(\sigma_{1}=0.004\) & \(\sigma_{2}=0.0001\). We can observe a damped periodic solution