Epidemic Spread Simulation with Cellular Automata

Shih Ching Fu Example output from SimDemic

This page outlines the work I completed for my Honours dissertation in 2002.

Virus and other disease outbreaks are attracting more and more media attention. Apart from the obvious health effects of infection, the economic impact can be substantial as illustrated by the avian flu outbreak in Hong Kong during 1997 and the foot-and-mouth disease (FMD) outbreak in Britain in 2000. In order to better understand, predict, and eventually contain epidemic spread, accurate models need to be devised.

Current epidemiological models are dominated by statistical and deterministic methods that do not take into account spatial variables. Considering that natural landscapes are typically far from homogeneous and uniform, it makes sense to incorporate spatial heterogeneity parameters to produce a better model. Cellular automata (CA) is a paradigm that is conducive for modelling space and my project focusses on investigating the applicability of CA to disease spread simulation.


SimDemic

SimDemic is the epidemic spread simulation that I wrote as part of my Honours research in 2002. It is based on the SIR epidemic model and uses a 2-D cellular automaton to emulate the spatial behaviour of a spreading infection.

My epidemic model is far from comprehensive and is intended only to provide preliminary evidence of CA's usefulness as a epidemic modelling paradigm.

Below are some pre-synthesized scenarios that show some of the capabilities of a CA epidemic model. Each applet runs the same set of CA rules, but has a different starting state for the cell grid. You will need Java installed on your browser for these applets to work.

The left panel of the interface depicts the extent of infection; the right panel shows the population density map. Both maps are of the same grid and updated synchronously. Note that just one infective host will turn a square red, whilst the saturation of the blue indicates how close to its carrying capacity a cell has become.

Further details can be found in my Honours dissertation provided below.

Homogeneous scenario

Varied population density

Corridors of spread

Barriers to spread


Some reading


Last modified: Tue Feb 28 09:10:30 WST 2006 Counter