Fig. 2.

The solution trajectory of system (2) with values from Table 2 starting from $\left(N_1\left(0\right),I_1\left(0\right),V_1\left(0\right),N_2\left(0\right),I_2\left(0\right),V_2\left(0\right)\right)=\left(\mathrm{900,200,0,10,5,0}\right)$ and time $T=7000$ days for several values of $u_1\left(t\right)=0.2,u_2\left(t\right)=0$ (upper panel), $u_1\left(t\right)=0,u_2\left(t\right)=0.2$ (middle panel), $u_1\left(t\right)=0.2,u_2\left(t\right)=0.2$ (lower panel). Final values are given in Table 3.