Possibly Tinea. A wide spread fungus. Makes lots of folks quite miserable.
If it is Tinea - then its fixable with this simple do it yourself home remedy method.
May take several weeks.
Also called ring worm, as over time it can creep, and leaves a curved scar behind.
It is a fungus. It's wide spread everywhere in the world.
1. wash the area with antiseptic soap
2. let it dry
3. sand the area with an emery board, gently
4. paint the "sanded" area with liquid iodine, with a small paint brush
5. do this twice a day. Take care - Iodine stains. So put the bottle in a box to make sure it does not tip. Make up a small kit box; Iodine, emery boards, paintbrush.
Always uses a clean towel, every time you bathe.
Means lot of washing, but that helps keep the fungus at bay.