Fig 2. Fraction of susceptible individuals at long times.

(a) Fraction S_∞/N of susceptible individuals that remain at long times as a function of the basic reproduction number R₀ for different degrees of population heterogeneity characterized by the values of α. The limit α → ∞ corresponds to the classic case with homogeneous populations (green). In the limit α → 0 populations are most heterogeneous (blue). (b) Fraction S_I/N of susceptible individuals as a function of R₀ at the peak where the number of infected is maximal for different α. (c) Ratio of infections after the peak S_m − S_∞ and infections before the peak N − S_m as a function of R₀.