Marleen Boelaert, M Arbyn, P VanderStuyft
Tropical Medicine & International Health
Geographical information systems (GIS) allow the mapping and analysis of spatial data. The multi-layer structure of GIS databases is an important feature of most such systems. If the basic map layer contains the administrative boundaries of an area other information layers can be superposed and displayed simultaneously. GIS also permit the spatial transformations of data such as the selection of all events within a certain radius around a point location. GIS therefore facilitate the progression from descriptive to analytical epidemiological work and help raise hypotheses about associations. Advanced features of GIS include tools for spatial statistical analysis as well as for spatial modeling. Industrial GIS applications have been growing at the annual rate of 25-35% over the past decade and are slowly invading the domains of tropical medicine epidemiology and public health. Mapping through GIS can help considerably in the assessment of environmental health risk. GIS are also being introduced in tropical disease control programs against sleeping sickness Chagas disease leishmaniasis schistosomiasis guinea worm and malaria. Cartographic display available through GIS can help national health policymakers identify risk areas their subsequent targeting and monitoring of interventions to those areas. Environmental epidemiologists are using GIS in research. GIS can also be effectively used in health services management at the district level but only after a thorough cost/benefit analysis has been conducted for given regions.