The 26-year-old's participation in the tournament was thrown into some doubt earlier this week after the winger sustained a groin injury in the 2-0 win over Manchester United.
As a result, Mirallas is poised to miss the Toffees' tussle with Arsenal for Champions League qualification, but says that he is thankful that his injury allows him to recover in time for his upcoming international commitments.
"In England, at first they thought I could not play in the World Cup," he told RTBF. "I was a bit dejected but when I returned to Belgium on Wednesday, I redid the tests and I'm relieved.
"It was confirmed that I was out for three to four weeks. It's better that it happened now than in three weeks, but I really wanted to finish the championship with Everton.
"I will miss playing. I wish I was still at Everton as we are still in the race for the Champions League."
Belgium were drawn into Group H alongside Algeria, Russia and South Korea.