The final line from the dvr news cast says there were many ground zeros all around the world. Leakage from Raydon Labs around the globe simultaneously turning people is very unlikely. The cities mentioned in the newscast do not share common water supplies. If Raydon labs did cause this outbreak it was on purpose, a preplanned and synchronized attack to end humanity. I could imagine an small amount of an infectious airborne agent being released on a timer in various cities. Infect a handful of people in each city and have them tell two friend and they tell two friends and so on and so on.