The Wendigo is a type of spirit among some peoples of the East Coast and Great Lakes. They are said to be spirits that cause cannibalism, and turn others by giving them a craving for flesh.
In my home state, we have a similar spirit, the Wechuge. It is a person whose spiritual ally is that of a spiritual beast or ancient giant who persuades them and hunts through them, causing them to taint themselves by feeding of man flesh.
These spirits are not so much a problem in the Athabaskan culture, they are potent spirit allies, that some identify with, and use in spiritual quests. The cure of course is the opposite of the spirits of wilderness, like the warm fire of camp life.
Interesting enough, there are similar spirits in europe, particularly that of Haggis spirits and Werewolves
A good book on the subject is Divine Hunger.