What lessons can we learn from the Japanese sarin attacks?

On 27 June 1994 a Japanese terrorist group, Aum Shinrikyo, released sarin in Matsumoto. Some 600 people were exposed: 58 were admitted to six hospitals and all recovered: seven casualties living close to the sarin release died outside hospital. This release followed an earlier attempt by Aum Shinrikyo to use sarin to kill the head of a religious sect perceived as a threat. In December 1994, a former supporter of the group was murdered by Aum Shinrikyo using VX. On 20 March 1995, Aum Shinrikyo launched a coordinated attack using sarin on the Tokyo subway system. Over 5000 "casualties" sought medical attention of whom 984 were moderately poisoned and 54 were severely poisoned; 12 died. Despite some initial difficulties, Japanese emergency units and local hospitals were able to respond reasonably rapidly. Analysis of the events reveals a number of important lessons for authorities as well as physicians to consider when preparing for such incidents.