We study by analytical methods and large scale simulations a dynamical model for the spreading of epidemics in complex networks. in networks with exponentially bounded connectivity we recover the usual epidemic behavior with a threshold defining a critical point below that the infection prevalence is null. On the contrary, on a wide range of scale-free networks we observe the absence of an epidemic threshold and its associated critical behavior. This implies that scale-free networks are prone to the spreading and the persistence of infections whatever spreading rate the epidemic agents might possess. These results can help understanding. computer virus epidemics and other spreading phenomena on communication and social networks.


Originally published in Physical Review E, v.63 no.6 (2001), 66117. DOI:10.1103/PhysRevE.63.066117. Dr. Vespignani is affiliated with Northeastern University as of the time of deposit.


complex networks, epidemics, containment, endemic states, dynamical models, scale-free networks

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Computer viruses, Computer networks




American Physical Society

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©2001 American Physical Society

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