The Alpha-Omega vaccine was a vaccine designed to counteract the Alpha-Omega virus.
General Matthew Shrieve had developed a vaccine so he and his men can kill off most of Hong Kong's population with the Alpha-Omega weapon without harming themselves. Amanda Waller later revealed it's existence to Oliver Queen, who later used it on himself, Tatsu, Maseo, and Akio Yamashiro. Unfortunately for Akio, he was too young and his immune system was not yet strong enough to be stimulated by the vaccine to counteract the virus.
Behind the scenes
- The portrayal of the vaccine is not accurate in real life. When a person is inoculated with a vaccine, it actually takes about two weeks for their immune system to fully develop anti-bodies against a specific virus or bacteria. As such, if it actually cured them of the virus, it would actually be a cure not a vaccine. However, it could contain a combination of both.