FIG. 4.

For SIR dynamics, effect of local behavioral response on epidemic prevalence and threshold: (a) epidemic prevalence R^∞ as a function of transmission rate λ for different values of α; (b) contour of R^∞ with respect to λ and α, where the white line is the prediction of Eq. (20). The gray region under the pink dash link indicates the epidemic prevalence $R^{\infty }<7\times {10}^{-4}$. Since the number of the initial infected seeds is I₀ = 5, we have $R^{\infty }\ge 5/N=5\times {10}^{-4}$ for the steady state. Other parameters are the same as for Fig. 1.