Absence of epidemic threshold in scale-free networks with degree correlations.
Random scale-free networks have the peculiar property of being prone to the spreading of infections. Here we provide for the susceptible-infected-susceptible model an exact result showing that a scale-free degree distribution with diverging second moment is a sufficient condition to have null epidemic threshold in unstructured networks with either assortative or disassortative mixing. Degree correlations result therefore irrelevant for the epidemic spreading picture in these scale-free networks. The present result is related to the divergence of the average nearest neighbor's degree, enforced by the degree detailed balance condition.
Boguñá
Marián
M
Departament de Física Fonamental, Universitat de Barcelona, Avenida Diagonal 647, 08028 Barcelona, Spain.
Pastor-Satorras
Romualdo
R
Vespignani
Alessandro
A
D004812:Epidemiologic Methods; D008962:Models, Theoretical; D016571:Neural Networks, Computer; D012944:Social Support