best take them to the vet--your son will have ringworm next--very contagious. i one battled it for over a year.hope someone can give you a cheaper solution, but, myself, this is what i would suggest.

We had a kitty with ringworm, and I'm sorry to say there was no cheap solution. Lime sulfur dips work wonders...perhaps your vet will allow you to buy some and bathe at home.

Keep in mind that ringworm spores can live forever and that lime sulfur or bleach are the only two things that really kill them. When Birdie had ringworm we quarantined her in her own little room, which we bleached top-bottom each week. We also had special clothing we wore in there and only in there, which was washed every other day with bleach.

Neither my husband nor I ever got it....and our other animals never got it either. Our vet was amazed considering the fact that he said Birdie's was the worst case he'd seen. I chalk it up to our diligence. It was WELL worth it in the end!
Gina

A few drops of Tea Tree oil spread on it every day should clear it up quickly.

We brought a kitten into the house that was covered. Our vet told us to get the powder from WalMart that is for athlethe's foot. Can't remember the name, but it stated right on the plastic bottle that it will treat ring worm. He had us dust each one of the liasions with the powder and brush it into the area with a tooth brush 3x's a day. None of the other kitty's nor house dogs got it and not my dh or it.....and it only took about a week to get them healed. It costs about 5 dollars for the powder. Be sure to use gloves when you do it and dust them good.. hope this helps.
there is a vacinne for it but vet said it's really not effective as a cure and only marginal for a preventive....

arkiema

I have been battling ringworm spots found on my three dogs . Athlete's foot cream worked really well . Buy the cheapest one you can find- I got some at Big Lots for 99 cents.
I ordered sulfur lyme dip from the internet- much cheaper than from the Vet . I bathed the dogs every two weeks with good long soaks .
All three dogs are clear and healthy now and no human caught ringworm . It was hardest to clear up the ringworm on my oldest dog - 15 years old . Should be much easier with a small kitten .

one of my cats ended up with ringworm and about 60 dollars later we cured it. Vet had to call in a prescription to Walmart and then I had to go pick it up and they mixed it with something there. Some type of flavoring for kitty to eat as well as a creme.....not a cheap visit that time....wish I had heard of some of these things before.......