The Spain international has missed the Blues' last three games due to hamstring and groin issues, and also spent some time in hospital with a virus.
Mourinho has confirmed that the virus was not the reason why the prolific striker was absent from Sunday's 1-1 draw with Manchester United, but rather his injury concerns.
"The virus is fine," the Daily Star quotes Mourinho as saying. "It was hard when he went to hospital and obviously it doesn't help to recover from the injury. But he didn't travel to Old Trafford because of the injury, not because of the virus.
"He aggravated the hamstrings because he played two matches in three days, and was not with us. QPR - one week more, I hope so."