My kids got it years ago from an 2 adopted cats their grandpa brought home. This was years ago so maybe things have changed but the vet dipped the cats in this horrid smelling medication and that took care of the cats immediately.
For the girls it took a little longer. One thing that I use and think it rules for a number of things is Tea Tree Oil. Here is a website but I'm sure there are plenty of others.
http://www.teatreeoiluses.com/tea-tr...es-human-2.htm