OK, let's try this until your next vet visit is scheduled (and perhaps you can find another vet in the meantime?)
Pick up any anti-fungal cream that says it treats 'ringworm' on the label. Dab it on these areas (carefully avoiding eyes/mouth) two or three times a day. Make sure you keep hands washed after every time you touch her.
Ringworm, if this is what it is, is not a 'worm', but a fungus. It often self-resolves (which may explain why this goes away and returns), but it is contagious to other animals and humans (it would look pretty much the same).
It's not uncommon in pet store and/or shelter animals; however, shelters usually find it and treat it before releasing the animal.
Since you're having her treated through the ASPCA, she's probably from Pet Smart? A rescue adoption? This would mean she was foster-homed before coming to you and was likely in with other rescued cats. It's really no one's fault that this might have been missed.
If it's not better in 3 to 10 days with treatment of anti-fungal, perhaps the next visit should evaluate for mange.
Mange might sound ominous, but these days it's very manageable once properly diagnosed.
Sound reasonable?
__________________
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You remain responsible, forever, for what you have tamed.
