Johnson, whose Ospreys side face Leinster in Dublin for the right to be crowned Magners League Champions next weekend, is recovering well from viral encephalitis, more commonly known as inflammation of the brain.
The Australian was taken ill just before the Ospreys' vital Magners League win over the Scarlets on April 2 and missed the away trips to Ulster and Leinster as a result.
But while Johnson admits that he has not yet recovered 100 per cent, he isn't letting the illness stand in his way of giving the Liberty Stadium outfit the best chance of being Celtic Kings on May 29.
"I'm not 100%, not where I want to be but certainly much better than I was a few weeks ago," said the former Wales and USA coach who joined the Ospreys last year.
"I'm up on my feet doing as much as I can with people around me.
"But when you're at this level and late in the year, you probably do less anyway.
"I came down with something and I wasn't sure what it was as I don't get sick a lot. It certainly took me by surprise.
"I took ill the week before the Biarritz match. Probably one of the dumbest things I did was fly to Biarritz. What really killed me was the flight, I certainly paid for it since."
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