My 4 yr old granson has a rash that started on is upper back and head. The sores are round, red, scaly and itchy. The scab over, bleed and now are becoming painful New sores are appearing on his genetiles, face, arms. They start out small and grow in the same spot and nothing is helping them get better. Multiple creams have been tried with no relief. The only thing that seems to help at all is if he goes swimming they begin to clear up? Any ideas?