Figure 4.

Sample paths for the number of infecteds observed in Monte Carlo simulations. Sample paths for the number of infecteds observed in Monte Carlo simulations of the stochastic process corresponding to dynamics (7). One hundred independent runs are illustrated by thin lines. Thick broken lines indicate the deterministic trajectory (A). The histogram shows the distribution for the times at which viruses went to extinction (B). 38 out of 100 runs never go to extinction, and cause outbreaks. The parameters are the same as in Figure 3, and K = 10⁸.