It's been two years since anthrax-tainted mail terrorized the nation in the wake of the September 11 attacks. Over the course of several weeks, five people died and 17 others became sick after being exposed to anthrax. No one has been arrested in those attacks. Michael OH-ster-holm is the Director of the University of Minnesota's Center for Infectious Disease Research and Policy. He says one of the most sobering discoveries to come out of the anthrax investigation is how easy it is to disperse the dangerous POWDER.