 Why did Charles think he was the last person alive?
There should be an epitaph for every man, big or little, but a really grand and special one for Loner Charlie. New York lay quietly below him. To any man, WHO HAPPENED TO BE THE LAST MAN ON EARTH! Within a year it was obvious to everyone that man was the only animal left on earth. Less than a month ago no more than a few thousand people remained in New York. And now.... "I've got to find out," Charles told himself. And again at the age of 10 each child returned to the Bureau for a recheck. Charles activated the switches that would flash a schematic map of New York on the screen. Charles was by himself, the last person alive in all of New York City.
 He had some sort of immunity
 His sickness was taking longer  He had some sort of immunity  He was the reason for the plague  He was meant for greater things