Abstract
Infectious diseases pose threats from natural and manmade sources, and arguably the situation is getting worse. The outbreak of the coronavirus causing the severe acute respiratory syndrome (SARS) shows that the world is linked by thousands of people traveling millions of miles every single day who can spread SARS or new strains of influenza with pandemic potential. The world is also becoming a more dangerous place, with rogue nations and terrorist networks aggressively seeking nuclear, chemical, and biological weapons. Of these, biological weapons are the cheapest to produce and likely the most attractive because they can be used anonymously.