It was long believed that the Dracunculus medinensis parasite, which causes guinea worm disease in humans, has a fairly simple life cycle: A person drinks water contaminated with copepods, or water ...

A brain-invading worm spread by rats and snails is making inroads into the United States. A study this week seems to show the nematode Angiostrongylus cantonensis, a.k.a. the rat lungworm, is now ...