Ederson, Scott Carson, Tommy Doyle, Eric Garcia, Cole Palmer and Ferran Torres all missed the midweek win over Manchester United due to the virus, whilst Gabriel Jesus and Kyle Walker were named on the bench for the first time since their recovery.
Guardiola says Ederson, Doyle and Torres could all return to training before the Birmingham game if they return negative tests, but whether Jesus and Walker are fit to start will depend on how ready they feel.
“Kyle and Gabriel came back on the bench for Old Trafford - we will see how they react in the training sessions,” he said at his pre-match press conference.
“It’s a mystery how the people who test positive will react afterwards. We don't know, every case is different.
“Some feel exhausted, some feel better. That's why you have to see how they feel after training sessions.
“But it’s incredibly good news they are back, they are healthy and they can join the team again.”
Sergio Aguero remains in line for a start against Birmingham.
With his minutes being carefully managed, the Argentine striker has made just four substitute appearances since returning from injury in December.
However, Guardiola says there have been encouraging signs in training that the Club's record goalscorer is getting back to peak fitness and he is expecting him to start on Sunday.
“Yesterday he trained really well,” added Pep.
“Today we are off. If tomorrow he feels good, he will play, yeah. His mood is better than ever, this is important. In the last two weeks, his reaction in his knee has been really good.
“He is going to start and his performance and his knee will dictate. We want good quality minutes.
"It will be great to have Sergio back and in good condition. He is optimistic.
"He says he wants to come back and score goals. We don't put pressure, but most of the games we need him because he is a striker."
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