It may be that the sooner this disease is caught, under competent medical treatment, the better your chances to survive.
However, it is true that had he survived, the floodgates would probably have opened to sick people. They've already opened anyway.
I don’t want to believe there was any nefarious reason Duncan died or wasn’t treated like anyone else in his condition. His treatment was very delayed, and there were other factors like no ZMapp and no matching blood type. It sounds like the hospital staff did everything humanly possible to save his life.
It may be that the sooner this disease is caught, under competent medical treatment, the better your chances to survive.
However, it is true that had he survived, the floodgates would probably have opened to sick people. They’ve already opened anyway.