My kids have changed school recently and they started bringing head lice home, at first we thought that was one time instance, but there are few families (including parents) that do seem to carry lice and don't treat them as they have nits clearly visible for some weeks now.
I went through two bottles of anti-lice shampoo and was wondering is there some treatment like dog collars for humans that one could simply carry with/on himself to avoid getting lice.
