K.D.
There is an anti-viral cream that a dermatologist can prescribe that will take care of it, but you have to follow the directions exactly for several weeks. It is a pain for little ones, as once the cream is applied, the spots then have to be covered up with bandages, etc. And there is a schedule that HAS to be followed, or it won't work. The other option is to just wait it out, as eventually the child with develop the anti-viral properties in their blood stream and they will go away but it can take years for that to happen. My son and several of classmates got those in Indonesia when we lived there. They call them water warts in Asia, as most kids get exposed to them in the swimming pools.
Hope this helps!