Are you sure its ringworm?
It could just be some sort of toxin coming out.
Thats what I suspect anyways, all kinds of weird things can happen.
Ringworm is a fungal infection and I dont think its that common unless you
are around animals (I got it a few times when I worked in an animal shelter for a year, the cats ALWAYS had it).
I say just keep going with the humaworm and see what happens, if it worsens you can look into getting some anti fungal cream for it and see if that helps.