A mathematical study of how anthrax spreads through the mail

A mathematician at Vanderbilt and an expert in infectious diseases at the New York University School of Medicine have teamed up to produce a mathematical model of how anthrax can be spread through the mail.

The model, which appears in the May 14 issue of the Proceedings of the National Academy of Sciences, simulates the recent outbreak of mail-borne anthrax deaths in the United States and demonstrates that all the known cases of infection can be explained by contamination spread through the mail from six original envelopes.

The analysis concludes that original anthrax-filled envelopes must have contaminated an additional 5,000 pieces of mail with significant but much lower levels of anthrax spores in order to account for the two deaths that appear have occurred from such cross-contamination. In the case of any future attacks of this type, the model provides a framework that can be used for the rapid identification and containment of any further outbreaks.

The model was developed by Glenn F. Webb, professor of mathematics at Vanderbilt, and Martin J. Blaser, the Frederick H. King Professor of Internal Medicine, chairman of the department of medicine and professor of microbiology at the NYU School of Medicine.

By David F. Salisbury
May 15, 2002