The Arsenal winger damaged knee ligaments with an hour played in the Three Lions' recent 2-2 draw with Ecuador in Miami.
Oxlade-Chamberlain picked up his ankle injury in the game with Ecuador in Miami
However, after extensive treatment and rehabilitation work, he is targeting a return very soon - motivated by the chance to play in his first World Cup
"It's coming along," he revealed. "Considering when the injury was, I'm really happy – as are the medical team – with how it's progressed.
"I'm doing some good fitness work. We'll keep pushing it – not too quickly, obviously – but I'm really positive about it and so is the medical team.
"We are not sure about timescales - we just know we are very positive about it."
He added: "Because it is a World Cup it is on a bigger scale and more people watch it - that gives you the extra motivation and buzz.
"It is what you watch as a kid growing up; it is what everyone back home is watching, everyone here and everyone around the world.
"But first things first, I have to get through my rehab, get back into training and push on. If selected and if needed, I will try to do what I usually do."
The 20-year-old was showing some dazzling flashes against the Ecuadorians - his first game in six weeks following another spell on the sideline with a groin injury.
But his contribution to that game was brought to a premature end in innocuous circumstances after a second-half tangle with Carlos Gruezo, and he admits his immediate concerns were that the injury would put an end to his hopes for Brazil.
Oxlade-Chamberlain was in good form against Ecuador prior to his injury blow
"I didn't think it was over completely, but I thought there might be a chance it was over," said Oxlade-Chamberlain.
"If this had happened in the season with your club, it's a blow, but it's not a massive injury. I wouldn't take took long to get over it.
"But just because of the timing with the World Cup, everyone panics. You do fear the worst. I knew it wasn't as bad as the other injury I'd had earlier on my knee.
"I actually sat in the scanner with the fingers crossed on both my hands for the whole 25 minutes.
"At the end I couldn't feel my fingers. That's literally how I sat. After I came out, our Doc saw the scan results and was pretty happy with them, considering what they'd feared.
"They'd thought it could have been a lot worse than it was. I was obviously a bit worried."
After watching on from the sidelines as England lost the first game of their World Cup campaign to Italy, Oxlade-Chamberlain wants to be back in the reckoning as soon as he can.
Inspired by his goal against Brazil in the Maracana a year ago, the former Southampton winger believes that he can recapture the form he was showing against Ecuador and hit the ground running again.
"Before the Ecuador game I hadn't played since the Semi-Final of The FA Cup," he explained. "In training, the way we train, it's so sharp it's like a match anyway.
"When I came back from the five-month injury it does take a bit longer to get into the swing of it, but with short-termers it's easier to hit the ground running.
"Having that taste last year, and being able to score against Brazil in the Maracana, and now being in the World Cup with a chance to emulate that, it's a massive motivation.
"I took that coming into this tournament and I still have that same thought in my head now, trying to emulate that.
"It's a nice memory for me to cling on to for the rest of my life. Hopefully there are more memories like that."
