IBM has already put some processing muscle into the fight against world health problems. Now they're adding a bit of software to the battle. Over the weekend, it announced the release of the source code and Windows and Linux executables for its Spatiotemporal Epidemiological Modeler, or STEM. The software was released under the Eclipse license.
As its name implies, STEM is dedicated to the modeling of epidemics, especially emerging diseases, as they spread through our increasingly connected world. According to an IBM software engineer, "STEM will allow public health officials to model the spread of a disease much like modeling a storm or hurricane—it allows us to produce a public health 'weather map' for the spread of a particular disease."
Lots of epidemiologists have generated specialized models of disease spread in the past, but IBM claims that STEM is flexible enough to handle anyone's needs: "The ultimate goal of STEM is to provide a common modeling platform powerful enough to be sufficient for all modeling scenarios and extensible in a way that allows different researchers to combine their efforts in developing exceptionally good models."
To that end, the package comes with extensive GIS data for most countries, which includes information on population density and transportation links. Researchers can then specify details of their specific disease models via XML files; other parameters are configurable via a GUI. Output can include animations of disease spread across maps of the countries being modeled. IBM is promoting the avian flu as a great use of STEM as a tool, and the project does seem promising: it allows researchers to overlay the disease's spread in human and domestic bird populations, and run the simulations in parallel. Other example projects are available for download.
STEM has been in the works for a while; a paper that describes it dates from early 2006. This release is the 0.2.0 version, but it's not clear what is new and different compared to earlier releases. The bigger question is whether a general but extensible model can ever outdo the performance of one specialized for a specific disease. Given the resources of IBM and many of the government health organizations it is working with, it seems entirely possible that STEM may manage this feat.