When my twins were young and just finishing up chicken pox (this is before the vaccine), the one with pale, thin skin (I think of it as Irish skin, inherited from his father) developed a rash that wouldn't quit. The doctors (several of them) fixated on scabies as a cause, and we went through all sorts of decontamination, then washed the whole famiy with some fairly toxic stuff. No effect, and the lesions kept changing from rash-like to whole-body itch and redness. I finally took him to a dermatologist who once more diagnosed scabies, but did mention that it could be a surface bacterial infection. A thorough bath in iodine (Povodine, actually) soap cured it in a couple days. If it's a fungal infection (candidiasis), the Povodine will kill it. Antibiotic ointments will not. The Povodine looks pretty bad (dark brown) but usually doesn't hurt like alcohol solution of iodine does, and washes out easily from most fabrics. It can't hurt, and if it works it's a diagnosis.