The model presented here served maily the purpose of illustrating the capabilities of Epigrass for simulating and analyzing reasonably complex epidemic scenarios. It should not be taken as a careful and complete analysis of a real epidemic. Despite that, some features of the simulated epidemic are worth discussing. For example: The spread speed of the epidemic, measured as the time taken to infect 50% of the cities, was found to be influenced by the centrality and degree of the entry node (figures 9 and 10). The dispersion tree corresponding to the epidemic, is greatly influenced by the degree of the point of entry of Spread of the epidemic starting at the city of Salvador, a city with relatively small degree (that is, small number of neigh-bors) Figure 8 Spread of the epidemic starting at the city of Salvador, a city with relatively small degree (that is, small number of neighbors). The number next to the boxes indicated the day when each city developed its first indigenous case.