The U.S. Anthrax Letters
A Confirmed Case of BW Agent Use
LEONARD A. COLE
A half-dozen letters, perhaps more, containing powdered anthrax spores were sent through the U.S. mail to journalists and politicians starting about a week after the attacks of September 11, 2001.1 As a result, 22 people became infected, half with cutaneous anthrax, half with inhalation anthrax; five of the latter died. In several instances, initial diagnoses failed to recognize Bacillus anthracis as the cause of infection; the first case was not confirmed until October 4. The outbreak was characterized as intentional soon after, as spores were found at improbable locations, but the extent of illness and contamination of buildings, offices, and postal facilities was not grasped for several more weeks. Attribution as to the perpetrator proved elusive and remained uncertain more than six years later.
The anthrax bioattack of 2001 confounded many earlier assumptions about use of a biological agent for hostile purposes, from the manner of delivery to the health effects on infected survivors. This chapter reviews the unfolding events, from the first case to be confirmed in early October through the last one on November 21, and subsequent efforts to clarify uncertainties about the attack.
Although much about the anthrax letters is now understood, important questions remain unanswered: still unknown are the motivation as well as the identity of the perpetrator; the manner of exposure by which two women were