Figure 2
Pandemic probability for a range of between-region travel rates and a range of transregional pandemic definitions. The “pandemic threshold number” refers to the minimum number of regions that must experience epidemics before a pandemic is declared. The pandemic probability is, in general, sensitive to the pandemic definition used, but the degree of sensitivity depends on network structure and travel rates. (a) Pandemic probability for a star network. The pandemic probability is, in general, highly sensitive to the pandemic definition used. (b) Pandemic probability for a fully connected network. The sensitivity of the pandemic probability to the pandemic definition used is significantly reduced at high travel rates.
