Dunne is likely to return to competitive action for the Republic of Ireland against Sweden in Dublin on Friday evening with Austria waiting in the wings in Vienna four days later as the Group C campaign comes to a head.
But the 33-year-old QPR defender has played only 25 minutes for his country since the Euro 2012 finals after missing an entire domestic season through injury, and O'Dea is on red alert.
He said: "I will be ready either way, as will everyone in the squad.
"But certainly he looks fit and well and knowing the Championship well, if he can get through games in that, he can get through games in anything.
"He is obviously fit and strong. It is good news. We want to qualify for the World Cup and he is obviously a massive part of it, so it's good news for the whole squad.
"We will wait and see. It's up to him and the manager, but certainly, I will be ready either way."
Dunne's fitness problems meant he missed the 0-0 draw with the Swedes in Stockholm in March, a game which saw Ireland effectively shackle dangerman Zlatan Ibrahimovic.
However, while the onus will be on Giovanni Trapattoni's defenders to keep the Paris St Germain striker at bay once again, O'Dea insists that task is one which will involve the whole team.
He said: "Sometimes you can concentrate too much on one player.
"If you can stop the service to him and him actually getting the ball in the first place, you go a long way towards stopping him.
"When you played against Manchester United, everyone talked about Ronaldo and Rooney - really it was Paul Scholes you needed to stop because if they don't have the ball, they can't do much with it.
"I think we will try to stop him from the front and not let the ball get anywhere near him, really."
Former Celtic defender O'Dea, 26, joined up with his international team-mates having swapped Toronto and the MLS for Ukraine having joined Metalurh Donetsk on a three-year deal.
However, a gruelling journey to his new club took its toll and led to an enforced lay-off.
He said: "I had travelled to Kansas with the Toronto squad to play, had to travel to Toronto and then on to Munich, to the Ukraine, and then 48 hours later I was playing my first game, and I never recovered after it, really.
"Basically my body collapsed, I just gave in. I had done too much. I was pushing it.
"I was halfway through a season, so I was very fit, but when I started in the games, I just felt drained.
"But they have been fantastic with me there. They just shut me down for a while. I did a little mini-pre-season, just to get moving again, and now I feel great."