Figure 6.
A growing population increases outbreak vulnerability and allows for sustained outbreaks. We show a sample time series with increasing population size (birth rate μ = 9.5 × 10−5 and κ = 1.8 × 10−9), and a starting population of N = 106. The susceptible population has been scaled by a factor of 1000 so that both the infectious and susceptible time series can be clearly seen in the figure. Initially, the reservoir transmission triggers large outbreaks and results in fast extinction events. As the size of the population and the number of susceptible individuals increases, infectious individuals tend to a dynamic endemic state with sustained outbreaks. All other parameters are as in table 2.