The spatial epidemiologic (r)evolution: a look back in time and forward to the future.

Spatial epidemiology enables you to better understand diseases or ill-health processes; investigate relationships between the environment and the presence of disease; conduct disease cluster analyses; predict disease spread; evaluate control alternatives; and basically do things an epidemiologist otherwise would have been unable to do and avoid many errors that otherwise may have been committed. Recently, the discipline of spatial epidemiology has advanced substantially, owing to a combination of reasons. The introduction of the electronic computer has clearly led this advancement. Computers have facilitated the storage, management, display and analysis of data, which are critical to geographic information systems (GIS). Also, because of computers and their increased capabilities and capacities, data collection has greatly expanded and reached a new level owing in large part to the advent of geographic positioning systems (GPS). GPS enables the collection of spatial locations, which in turn present yet another attribute (location) amenable to consideration in epidemiologic studies. At the same time, spatial software has taken advantage of the evolution of computers and data, further enabling epidemiologists to perform spatial analyses that they may not have even conceived of 30 years before. Capitalizing on these now, non-binding technologic constraints, epidemiologists are more able to combine their analytic expertise with computational advances, to develop approaches, which enable them to make spatial epidemiologic methods an integral part of their toolkits. Instead of a novelty, spatial epidemiology is now more of a necessity for outbreak investigations, surveillance, hypothesis testing, and generating follow-up activities necessary to perform a complete and proper epidemiologic analysis.