Skin Problems When is ringworm healed

How do I know when ringworm is healed. I have 3 piggies with it but they have it in varying degrees. I have been treating them for a week and Cocoa just has one spot on her nose that the hair has grown back and one behind her ear that looks better. Butterscotch has a big patch about the size of a quarter on his back that the hair has grown in a 1/4 of an inch and one spot on his nose that the hair is growing back too. My third Brownie has it bad!!! the top of his nose/between his eyes is growing back in a few places, his ears look better. Between his ears is a pencil eraser size that no hair is growing back in and his worst spot on his neck that is oval but an inch and a half wide and as tall as a penny has some hair growing back on the right side but the other is bald as can be but I don't see the red ring as much just an overall redness. Oh yeah I notice yesterday on his nose/top lip a small crusty area that I started treating yesterday. Do I keep treating them all till all of them are healed? And what is considered healed. My daughter got it from them and I have been treating her for a week and her two spots are almost gone. I can barely see them so I know that her treatment is almost over but she can show more rings for 2 more weeks so I have to keep an eye on her.