There was a This American Life/Radiolab story about a guy who rolled his own Helminthic Therapy. If it weren't for the fact that the therapy was illegal (which is a whole other issue) and therefore very difficult for him to get, it would hardly have been a "story." Just an amazing cure for allergies/autoimmune problems. But the story was really in how he had to wander all over Africa shuffling through latrines to get a few hookworms. http://www.thisamericanlife.org/radio-archives/episode/404/e... . It's act 3.

Apparently the correct term is helminthic therapy. Interesting.

I gather that that sort of thing mostly has applications where autoimmune issues are concerned.