RE: a 14 year old which had survived.
Is the boy now IMMUNE from the ebola virus?
Is he immune? I would say at least for a time. Tingle those antibodies...and I believe they'll tingle easier the next time. But as the years progress, they tire...almost like it takes a smaller group of antibodies so why exist...and they deplete themselves.
Almost totally depleted, years later, you have lost that immunity.