The 22-year-old fractured his foot during the Three Lions' 1-0 friendly win over Denmark in March and has been restricted to just two substitute appearances so far since his return.
England faces friendlies with Peru, Honduras and Ecuador prior to the World Cup, games that Wilshere is keen to use as exercises to help him return to full fitness.
"I'm not match fit. The only way you get match fit is by playing matches," he told The Sun. "So I'm as fit as I can be without playing matches.
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"I've done as much as I can, now I just need a few games. It's a different kind of fitness - it comes back quickly. If I play in a few of the friendlies, I'll definitely be match fit."
Included in the 23-man squad for the tournament despite his injury concerns, Wilshere is delighted to have been given a show of faith by manager Roy Hodgson.
"I was nervous. I would have been devastated if I hadn't gone but it's a great feeling," he enthused.
"I wasn't fit towards the end of the season so it was a bit touch and go. I think the boss at England knew that but he had been speaking to Arsene Wenger and he came to the decision that I should go. I'm delighted."