Spatial modeling of cholera epidemic: A Law of Large Numbers

TL;DR

This paper introduces a stochastic spatial model for cholera spread on a lattice, proves a Law of Large Numbers linking it to a deterministic model, and discusses potential fluctuations and scaling limits.

Contribution

It establishes a Law of Large Numbers for a spatial cholera epidemic model, connecting stochastic and deterministic approaches.

Findings

Stochastic model converges to deterministic model in large populations

Framework for analyzing fluctuations and deviations in epidemic spread

Discussion of different scaling limits for the model

Abstract

In this paper we propose a Stochastic model for studying a spatial cholera epidemic spreading where communities (Humans and Bacteria) are spatially distributed on a one-dimensional lattice and the bacteria are transported along a network links that are thought as the hydrological connection in the studied area. We prove a Law of Large numbers which suggest that in large communities (both Human and Bacteria) the stochastic model behave as a deterministic spatial model proposed and studied in the literature and therefore it is quite unavoidable to ask how large fluctuations effect can occur between these two version. That question will be treated in a forthcoming work as large deviations estimates. We also discuss at the end of the work different possible scaling that could be treated using similar mathematical tools and which lead to different limits.