Optimally Allocating MedKits to Defend Urban Areas from Anthrax Attacks

Abstract

The deliberate release of aerosolized anthrax spores in a large city will expose thousands to this deadly disease. Although state and local health departments have developed contingency plans for promptly opening points of dispensing (PODs) and distributing antibiotics to those exposed after an attack is detected, other risk mitigation strategies have been proposed. This study focuses on the pre-event placement of pharmaceuticals in individual households for use only as directed by public health authorities. The pre-deployed medications are commonly known as “MedKits.” This paper considers the problem of a defender who wishes to minimize the expected fatalities of an anthrax attack by allocating a limited number of MedKits to various urban areas. Under the condition that the attacker wishes to maximize the expected fatalities, the defender’s optimal policy is to keep all of the potential targets equally attractive. The paper presents a methodology for finding this optimal policy. The paper considers a specific example using ten urban areas in the United States and compares the optimal policies with those in which the MedKit allocations are proportional to population. The approach can be adapted to consider a wide range of scenarios and local factors to help public health officials manage the risk of an anthrax attack. Having good solutions to this problem should be valuable to public health officials who are considering how to pre-deploy MedKits.