Essien had hoped to return for this Sunday's home match with Stoke, but after complications in his rehabilitation from a knee injury the 27-year-old fears he may not even be ready to lead his country to South Africa.
Asked if he thought he would be fit for the World Cup, Essien said: "As at now I don't know. I am just taking it day by day and if I can make it I will.
"If not then I will have sit at home and support the team like every Ghanaian.
"Until I know how the injury improves in the coming days and weeks, it will be difficult to say whether I will make the World Cup or not."
Essien suffered the knee injury while on national team duty at the African Nations Cup in January as Ghana went on to lose in the final to Egypt.
The midfielder is central to Ghana's hopes in South Africa, but with their first game against Serbia on June 13 he is reluctant to play unless fully fit.
"Yes it will be (disappointing to miss out) but the World Cup is the best and most difficult football tournament in the world and I would rather be there fully fit," he added on his official website www.michaelessiengh.com.
"We will just have to wait and see."
Essien had originally hoped to be back in action in time for Chelsea's home Champions League leg against Inter Milan.
But his knee continued to swell up and the player underwent four lots of surgery inside a fortnight.
He began a running programme as a part of his rehabilitation last week, but suffered discomfort in his knee which further slowed his recovery and resigned him to sitting out the remainder of the season.
"I will not make the Stoke game and to be honest it is possible my season for Chelsea may be over," he added.
"It is still down to the medical team but it looks more unlikely that I will play for Chelsea again this season.
"I have been dreaming about coming back and helping the team win a trophy or two like last season but sometimes dreams don't always come true.
"I am supporting the other guys in different ways at the training ground and I have every confidence that they will deliver."
He added: "The medical team are doing a brilliant job and I can't thank them enough.
"I started running last week but had to stop because of slight pains I was feeling in my leg. It is a minor setback which I could do without but that is part of the game we play.
"It has ups and downs and one has to stay focused."