Mead, who was England's top scorer in their European Championship title win last year, ruptured her anterior cruciate ligament while playing for her club Arsenal.
England are in Group D at the World Cup, which will be held from July 20th to August 20th in Australia and New Zealand, and Wiegman told reporters it was too soon to be making any decisions about the striker.
"It's a little early to say. I don't want to push it," the Dutchwoman added.
"She's had so many things going on in her life. We'll see how her rehab goes then we'll look at the future. I don't want her to look too far forward right now because of her situation."
Wiegman also wanted to give Mead time to recover following the death of her mother due to ovarian cancer last month.
"She had of course other private issues. I left the knee situation until now as I just wanted her to be OK and get settled with the situation and sadness she had around her," Wiegman added.
"She told me she's doing well. She really wants to make it (the World Cup). First, she needs to settle and we will see from there. For now, I won't push that."
