Figure 1

Two possible cases of the intersection of the curves \(\pmb{G(I)}\) and \(\pmb{H(I)}\) indicating the existence of positive equilibria. (a) \(\Lambda=15\), \(\beta_{1}=0.0008\), \(\beta_{2}=0.0006\), \(m=30\), \(\mu=0.05\), \(\gamma=0.2 \). \(R_{0}=0.96<1\). (b) \(\Lambda=15\), \(\beta_{1}=0.002\), \(\beta_{2}=0.0018\), \(m=30\), \(\mu=0.05\), \(\gamma=0.2 \). \(R_{0}=2.4>1\).