One pathogen does not an epidemic make: a review of interacting contagions, diseases, beliefs, and stories

Laurent Hébert-Dufresne1,2,3,4, Yong-Yeol Ahn5, Antoine Allard1,6

  • 1Vermont Complex Systems Institute, University of Vermont, Burlington, VT USA.

Npj Complexity
|September 4, 2025
PubMed

Insights

Contagion models across sciences often ignore interactions between spreading elements. This review explores how incorporating these interactions improves understanding and calls for a unified science of contagions.

Area of Science:

  • * Utilizes interdisciplinary approaches in mathematical modeling and network theory.
  • * Bridges natural sciences (epidemiology, genetics) and social sciences (sociology, economics).

Background:

  • * Contagion models are widely applied across diverse scientific fields, from biology to computer science.
  • * Current models often treat contagions in isolation, neglecting real-world interactions.
  • * Interactions within and across hosts significantly impact contagion dynamics.

Purpose of the Study:

  • * To review interaction mechanisms in social and biological contagions.
  • * To survey existing models and frameworks for incorporating these interactions.
  • * To identify challenges and future directions in contagion modeling.

Main Methods:

  • * Comprehensive literature review of contagion models and interaction mechanisms.
  • * Analysis of mathematical frameworks for modeling coupled spreading processes.
  • * Synthesis of findings from natural and social science contagion studies.

Main Results:

  • * Interactions between contagions are prevalent and significantly alter spreading dynamics.
  • * Existing models often fail to capture these crucial interdependencies.
  • * Challenges exist in inferring interactions and scaling complex models.

Conclusions:

  • * A unified science of contagions is needed, integrating social and biological perspectives.
  • * Future research should focus on developing scalable models that account for interactions.
  • * Interdisciplinary collaboration is essential for advancing contagion science.

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