I see one simple issue with your OP: Viruses cannot be cured, only treated. Vaccinating an infected individual would not turn them back if they already died, only help the body fight off the infection if they were merely sick. That would mean that those who turned initially and up until a vaccine was found would permanently be dead. Sorta like how you can't give someone a vaccine for polio after they already died of polio. 

Aside from that logic loophole I spotted, I'm interested in giving this a whirl.