Velocity and hierarchical spread of epidemic outbreaks in scale-free networks

Phys Rev Lett. 2004 Apr 30;92(17):178701. doi: 10.1103/PhysRevLett.92.178701. Epub 2004 Apr 27.


We study the effect of the connectivity pattern of complex networks on the propagation dynamics of epidemics. The growth time scale of outbreaks is inversely proportional to the network degree fluctuations, signaling that epidemics spread almost instantaneously in networks with scale-free degree distributions. This feature is associated with an epidemic propagation that follows a precise hierarchical dynamics. Once the highly connected hubs are reached, the infection pervades the network in a progressive cascade across smaller degree classes. The present results are relevant for the development of adaptive containment strategies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Disease Outbreaks*
  • Immunization / methods
  • Infections / epidemiology
  • Infections / transmission
  • Models, Theoretical*
  • Poisson Distribution