After a virus kills a significant amount of the global population the United Nations uses the devastation to assert themselves as a world government. The virus started in animals and mutated to effect human. After years of the virus the UN decides to separate the infected from uninfected. Scientist haven't been able to find a vaccine for the virus and it continues to mutate. Decades after its introduction to the world the virus is now mutating the human genome. People are starting to be born with animalistic features.