Natural human mobility patterns and spatial spread of infectious diseases

TL;DR

This paper presents a model of human mobility that captures realistic spatial epidemic spread, revealing unique dynamical features and thresholds not seen in traditional diffusion models, with implications for epidemiology and ecology.

Contribution

It introduces a bi-directional mobility model for epidemics that differs from reaction-diffusion approaches, providing new insights into epidemic front velocity and outbreak thresholds.

Findings

Epidemic front velocity saturates with increased travel rate.

A novel stochastic threshold for outbreak attack ratio is identified.

Model captures realistic human mobility effects on disease spread.

Abstract

We investigate a model for spatial epidemics explicitly taking into account bi-directional movements between base and destination locations on individual mobility networks. We provide a systematic analysis of generic dynamical features of the model on regular and complex metapopulation network topologies and show that significant dynamical differences exist to ordinary reaction-diffusion and effective force of infection models. On a lattice we calculate an expression for the velocity of the propagating epidemic front and find that in contrast to the diffusive systems, our model predicts a saturation of the velocity with increasing traveling rate. Furthermore, we show that a fully stochastic system exhibits a novel threshold for attack ratio of an outbreak absent in diffusion and force of infection models. These insights not only capture natural features of human mobility relevant for the geographical epidemic spread, they may serve as a starting point for modeling important dynamical processes in human and animal epidemiology, population ecology, biology and evolution.