Introduction to Unit 6: GIS and Infectious Diseases

This is the sixth unit in the module ‘GIS for the Analysis of Health’. This unit describes the application of GIS for analysing infectious diseases. Infectious diseases are spread by a specific kind of contact and are caused by a living organism such as a virus or bacteria. During the course of an outbreak, the spatial distribution of an infectious disease often changes very rapidly over time. Thus, many of the GIS techniques used with infectious disease data assess patterns in both space and time.

There are 5 subsections in this unit:

1. Spatial diffusion
2. Infectious disease and population movement
3. Variability in disease agents
4. Temporal and geographical trends in disease outbreaks
5. Map sequences

 
This first subsection provides an overview of ‘spatial diffusion’, the process by which disease spreads from one location to another. The second part of the unit, ‘infectious disease and population movement’, considers the origins of data on infectious disease cases. The origins of case data are important, since apparent geographical patterns may be an artifact of data compilation procedures and may not reflect the actual spatial distribution of disease risk.

The third subsection describes the use of GIS to analyse spatial ‘variability in disease agents’. Disease agents are the bacteria, viruses and other pathogens that cause infectious diseases. Different biological strains of these agents exist and may differ in their virulence and patterns of diffusions. GIS may be used to identify such differences.

The fourth part of the unit, ‘temporal and geographical trends in disease outbreaks’, looks at the methods by which infectious disease outbreaks may be analysed, given their inherently temporal nature. This part of the unit focuses especially on the Knox test, which identifies disease cases clustered together in space and time. The fifth subsection looks at how ‘map sequences’ can be used to visualize infectious disease outbreaks and focuses especially on the use of map animation for this purpose.
Expect to spend about 1 week working through these materials. Note that there is no assessed work for this unit.

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