Invasion threshold in heterogeneous metapopulation networks

Vittoria Colizza; Alessandro Vespignani

doi:10.1103/physrevlett.99.148701

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arXiv · 0802.3636

Invasion threshold in heterogeneous metapopulation networks

Vittoria Colizza·Alessandro Vespignani

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Abstract

We study the dynamics of epidemic and reaction-diffusion processes in metapopulation models with heterogeneous connectivity pattern. In SIR-like processes, along with the standard local epidemic threshold, the system exhibits a global invasion threshold. We provide an explicit expression of the threshold that sets a critical value of the diffusion/mobility rate below which the epidemic is not able to spread to a macroscopic fraction of subpopulations. The invasion threshold is found to be affected by the topological fluctuations of the metapopulation network. The presented results provide a general framework for the understanding of the effect of travel restrictions in epidemic containment.

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Vittoria Colizza, Alessandro Vespignani. 2008-02-25. Invasion threshold in heterogeneous metapopulation networks. https://doi.org/10.1103/physrevlett.99.148701

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