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arXiv · 2105.08992

Synergistic epidemic spreading in correlated networks

Shogo Mizutaka·Kizashi Mori·Takehisa Hasegawa
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Abstract

We investigate the effect of degree correlation on a susceptible-infected-susceptible (SIS) model with a nonlinear cooperative effect (synergy) in infectious transmissions. In a mean-field treatment of the synergistic SIS model on a bimodal network with tunable degree correlation, we identify a discontinuous transition that is independent of the degree correlation strength unless the synergy is absent or extremely weak. Regardless of synergy (absent or present), a positive and negative degree correlation in the model reduces and raises the epidemic threshold, respectively. For networks with a strongly positive degree correlation, the mean-field treatment predicts the emergence of two discontinuous jumps in the steady-state infected density. To test the mean-field treatment, we provide approximate master equations of the present model. We quantitatively confirm that the approximate master equations agree with not only all qualitative predictions of the mean-field treatment but also corresponding Monte-Carlo simulations.

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Shogo Mizutaka, Kizashi Mori, Takehisa Hasegawa. 2021-05-19. Synergistic epidemic spreading in correlated networks. https://doi.org/10.1103/physreve.106.034305

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