SIS Epidemic Spreading under Multi-layer Population Dispersal in Patchy Environments

TL;DR

This paper models SIS epidemic spreading in multi-layer networks with patchy environments, analyzing stability, equilibria, and optimal interventions using Lyapunov methods and convex optimization.

Contribution

It introduces a multi-layer network model with dispersal via CTMCs and provides stability analysis, equilibrium characterization, and optimal intervention strategies.

Findings

Existence of multiple equilibria under different parameters.

Almost global asymptotic stability of equilibria.

Effective intervention strategies derived from convex optimization.

Abstract

We study SIS epidemic spreading models under population dispersal on multi-layer networks. We consider a patchy environment in which each patch comprises individuals belonging to different classes. Individuals disperse to other patches on a multi-layer network in which each layer corresponds to a class. The dispersal on each layer is modeled by a Continuous Time Markov Chain (CTMC). At each time, individuals disperse according to their CTMC and subsequently interact with the local individuals in the patch according to an SIS model. We establish the existence of various equilibria under different parameter regimes and establish their (almost) global asymptotic stability using Lyapunov techniques. We also derive simple conditions that highlight the influence of the multi-layer network on the stability of these equilibria. For this model, we study optimal intervention strategies using a convex optimization framework. Finally, we numerically illustrate the influence of the multi-layer network structure and the effectiveness of the optimal intervention strategies.