Development of a risk-priority score for category A bioterrorism agents as an aid for public health policy.

In developing public health policy and planning for a bioterrorist attack or vaccination of military personnel, the most common method for assigning priority is using the probability of attack with a particular agent as the single criterion. Using this approach, smallpox is often dismissed as an unlikely threat. We aimed to develop an evidence-based, systematic, multifactorial method for prioritizing the level of risk of each category A bioterrorism agent. Using 10 criterion, anthrax scored the highest, followed by smallpox. Tularemia was the lowest scoring agent. We suggest that such a system would be useful for developing public policy, stockpiling of vaccines and therapeutics, vaccination of military personnel, and planning for public health responses to a bioterrorist attack.