Random graphs, infectious diseases and vaccination strategies Tom Britton, Stockholm University Abstract: Random graphs of various types can be used to describe the social structures in a community. Given such a graph a simple epidemic model can be defined in which individuals may infect a subgroup of its acquaintances. In order to avoid a major epidemic outbreak the community might be partly vaccinated. In the present talk we study these types of problems with focus on graphs where the degree distribution is heavy-tailed, but other than that completely random. For such graphs we derive results determining under what criteria a major outbreak may occur, and for what vaccination policies such outbreaks are avoided.