The world had fallen apart because the world pretty much ended, not leaving many humans left alive. A big astroid had hit the earth destroying more than the half world. There was many wildfires, tsunamis and storms leaving the worold in shambles

When a laboratory got destroyed a virus that killed humans and turned them into "creatures" broke out and killed many humans. There sas no cure and no one knew how to stop it. The virus affected the brain and made them agressive and if you get bitten or scratched you get infected. Ko one knows if theyre gonna find a cure or how many people are left on earth.