Alex Lee Movie Plot

My movie will take place in a post-apocalyptic world, where an virus called "The Gastrea Virus" has infected most of the human population. People infected will eventually become a Gastrea regardless of whether or not they have died yet. Gastreas infect people by biting their victims and injecting the virus into them. Eventually, the virus alters the DNA of the host and turns them into a Gastrea. The main character named Satomi and his small group of survivors must try and find a cure for the Gastrea Virus while trying to defend themselves against the army a Gastrea.