The Kameido anthrax incident: A microbial forensic case study

The Aum Shinrikyo, a Japanese religious sect, first came to worldwide attention in 1995 when the sect attacked the Tokyo subway system with sarin, a chemical nerve agent. Subsequent investigations revealed that the members had also attempted to develop and utilize biological weapons. In mid-1993, a bioterrorist attack with an aerosol containing Bacillus anthracis spores had been launched in Kameido, Japan. The attack’s impact was limited to complaints about foul odors lodged with environmental health authorities by neighborhood residents. Investigations in 1999-2000 proved that B. anthracis had been released, and that the involved strain was identical to that used in the Sterne veterinary anthrax vaccine. Epidemiological surveys found no evidence of associated human illness. The investigation’s success was possibly due to application of molecular strain subtyping. The lessons learned from the Kameido incident and their implication for law enforcement activities related to bioterrorism are discussed.