1634 Days to Live

I never would've thought something like this would happen. I always believed these kind of things only existed in movies and fictional stories.
If someone would've asked me how I'd want the world to end, I would've laughed and said a zombie apocalypse. We all think it would be so cool to kill some zombies, smash their brains, and use creative ways to dispose of them. We'd even joke about becoming one of them and eating our friends.
A pharmaceutical company claimed to have found the cure for Alzheimer's disease. They tested it on various geriatricians who, at first, seemed to respond well to the cure until they started convulsing one by one. Their heart rates started increasing, their blood pressure started rising. Until suddenly, they just... stopped. They laid immobile for a moment or so until their pulses started to beat again. It shocked everyone when the patients ripped off their restraints and attacked the scientists. Little by little, the madness started spreading until the entire world was infected. Only a few survivors remained.
How do I know?

Because I was there when it happened.