The helpless (Liam Payne)

In 2014, a young boy was diagnosed with an unknown disease.
His doctor called him "The helpless."
They found no cure, and the disease was very contagious.
It was said to spread when the victim died, some kind of toxic gas would be released from the corpse.
If you were close enough, it would be passed on to you.
What happens when the world is filled with death?
Who will make it out?
Who will survive?