Complex dynamics of synergistic coinfections on realistically clustered networks

Laurent Hébert-Dufresne1, Benjamin M Althouse2

  • 1Santa Fe Institute, Santa Fe, NM 87501; laurent@santafe.edu.

Insights

Network clustering can accelerate disease spread during synergistic coinfections, contrary to expectations. This occurs when coupling strength matches clustering, potentially causing explosive outbreaks on clustered networks.

Area of Science:

  • Epidemiology
  • Mathematical Biology
  • Network Science

Background:

  • Coinfection dynamics and contact network structures are typically studied separately.
  • Disease propagation is generally hindered by contact network clustering.

Purpose of the Study:

  • To investigate how contact structure clustering affects the dynamics of multiple interacting diseases.
  • To explore the conditions under which clustering can accelerate epidemic spread in coinfection scenarios.

Main Methods:

  • Developed a mean-field model for coinfection of two diseases with susceptible-infectious-susceptible dynamics.
  • Analyzed interactions on modular networks and introduced a tertiary infection criterion.

Main Results:

  • Clustering can unexpectedly speed up epidemic propagation in synergistic coinfections when coupling strength matches clustering.
  • Observed first-order transitions in endemic states, leading to explosive outbreaks.
  • Identified clustered networks as unique locations for explosive outbreaks under specific conditions.

Conclusions:

  • Clustering's impact on disease dynamics is complex and context-dependent, especially in coinfection scenarios.
  • Results highlight the importance of considering network structure in epidemiological models.
  • Called for more detailed epidemiological data on interacting coinfections.

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