SARS

The ability to distinguish living people from walking corpses becomes nearly impossible when the SARS virus turns the majority of the world population into zombies, and only 1,000 survivors remain. In 2009 the virus made the leap from insects to humans, sealing the fate of the human race. Six years later the world as we know it has ended, and a dark new age has dawned. With the human population dwindling to a dangerous low, the few uninfected now struggle to find a place to start a new life, away from the infected ghouls that stalk them relentlessly.