I don't know of any way to get the hair to grow faster. It will grow back though, and that is the important thing.
Blue Star is an over the counter ointment used for humans, for fungal infections. That is what Ringworm is, a fungal infection of the layers of skin.
Anytime we have had to use it, one time worked, cleared it up, and the hair started growing back.
You should be able to find it at any Wal-Mart, Walgreen's, or any drug store. Just ask the pharmacist for it.
A real cheap fix to a show cattlemens nightmare!!!