Selective Smallpox Vaccination After Bioterror Attack? Computer modelling weighs in

The U.S. and European nations are stockpiling smallpox vaccines and training personnel to hand them out quickly if the disease is ever unleashed by bioterrorists.

But exactly how, when and to whom would the vaccines be administered? Ideally, all the public would be vaccinated. But this is almost impossible to do in an emergency.

Research published in Nature (summarized in Yahoo! News) describes a study that used a high-powered computer model to simulate exactly how the disease would spread through Portland, Oregon. Using traffic flows, knowledge of shopping habits and social contacts, the simulation revealed there are predictable times and locations where people mingle and are ripe for contagion.

That throws up several options other than mass vaccination as a reply to a bioterror attack, according to the authors, led by Stephen Eubank, of Los Alamos National Laboratory (LANL) in New Mexico. The possibilities include vaccinating the most gregarious individuals in a population, closing down the most-visited locations, such as big shopping complexes or vaccinating everyone who visits them.

The LANL study is one of four being funded by the MIDAS (Models of Infectious Disease Agent Study) initiative, sponsored by the National Institute of General Medical Sciences (NIGMS), a part of the National Institutes of Health (NIH). Three MIDAS grants will support the creation of mathematical models to study various aspects of infectious disease epidemics and community responses. The fourth funds researchers to develop a central database to organize information from the other three groups. It also supports the development of user-friendly computer modeling tools for the broader scientific community, policy makers and public health officials to use to simulate epidemics and response strategies.