It is called cutaneous larva migrants, and it occurs when humans become infected with hookworms. H​umans, especially children get hookworm from touching dog or cat feces .....then putting their hands in their mouths!!! This can happen while playing in YOUR yard !!! You can also get this by walking barefoot through dirt or sand, where poop has been left behind. The larve can penetrate bare skin....so please keep in mind to Always have your yard and play area free from poop !!!