The 48-year-old singer was hospitalised with the potentially-life threatening illness in Vienna, Austria, last November and admits he "dodged a bullet" in returning to full health.
George - who had pulled out of a show in London`s Royal Albert Hall weeks before he was rushed to hospital - said: "It`s like I just dodged a bullet.
"I cancelled that show but didn`t get myself checked out. I took it for granted that I`d just fought off flu.
"I went and played for another three weeks in Europe. And then one afternoon I was having lunch and suddenly felt really odd and said to everyone that I need to go and lay down for half an hour on my own.
"And that`s the last thing I remember for fiveweeks. It was three weeks of them trying to save my life and two weeks awake."
George - whose new single `White Light` was inspired by his brush with death - admits he was like a "feeble old man" as he recovered from the illness and even had to learn to walk again because his muscles had wasted away.
He told BBC Radio 2`s Chris Evans: "I literally had to learn to walk again and weird stuff, because when they keep you sedated for that long your muscles literally atrophy at an incredible rate. And I just woke up like this feeble old man."
The `Faith` hitmaker still struggles to talk about the period of illness, but admits the severity of his condition was played down to avoid more scrutiny.
He said: "If they`d known how bad things were, it would have been a `death watch` kind of thing.
"So it wasn`t until I came out that we told people, that they had any clue. But for three weeks it was touch and go.
"I think maybe the reason I find it still a little bit upsetting to talk about is that because it was so random.
"When something like that happens in such a random fashion I think it takes a while to think that life is safe again."