Hello. My Granddaughter Has Eczema And Was Recently Diagnosed With

Hello. My granddaughter has eczema and was recently diagnosed with scabies. I don't know where she could have picked this up. She is 2 years old and don't attend daycare nor have any siblings at home. She is covered with bumps and they came all of a sudden. The allergist prescribed permethrin. I've done one application and I see a lot of them starting to look like they are dried up. Does this means the cream is working, and about how long before these bumps disappear. Also how could she have picked up scabies to begin with? Thanks for your time.