Moment approximation of infection dynamics in a population of moving hosts

Bruno Bonté1, Jean-Denis Mathias, Raphaël Duboz

  • 1Laboratory of Engineering for Complex System (LISC) of the French National Research Institute for Science and Techniques in Environment and Agriculture (IRSTEA), Aubière, France.

Plos One
|December 29, 2012
PubMed

Insights

This study introduces a moment approximation (MA) method to efficiently model host contact dynamics in epidemiology. The MA model closely matches individual-based models (IBMs), improving disease spread simulations in animal populations.

Area of Science:

  • Epidemiology
  • Computational Biology
  • Mathematical Modeling

Background:

  • Epidemiological models often use static networks, but real-world host contact structures are dynamic.
  • Simulating large populations with individual-based models (IBMs) is computationally intensive.
  • Understanding host movement and contact is crucial for disease spread dynamics.

Purpose of the Study:

  • To develop and validate a moment approximation (MA) method for approximating stochastic individual-based models (IBMs) in epidemiology.
  • To assess the accuracy of the MA method compared to IBMs and mean-field (MF) models.
  • To apply the MA method to model avian influenza (H5N1) spread in poultry flocks.

Main Methods:

  • Developed a moment approximation (MA) method to create a deterministic model from a stochastic individual-based model (IBM).
  • Compared simulation results from the MA model, an IBM, and a mean-field (MF) model.
  • Applied models to simulate the spread of avian influenza (H5N1) in a poultry flock.

Main Results:

  • The MA model demonstrated close agreement with the IBM simulations.
  • The study highlights the necessity of incorporating host displacement and contact processes into epidemiological models.
  • The MA method provides a computationally efficient alternative to IBMs for large populations.

Conclusions:

  • The moment approximation (MA) method is a viable and accurate approach for modeling dynamic contact processes in epidemiological studies.
  • Accurate representation of host behavior, including movement and contact, is essential for effective disease spread modeling.
  • This work offers a reusable framework for approximating complex stochastic models in epidemiology and other fields.

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