This is the most unbelievably disgusting thing I have ever heard.

It’s Maggot debridement therapy, or basically the medical use of sterilized maggots on open wounds. From the link on Boing Boing:

The larvae preferentially consume dead tissue (steering clear of live), they excrete an antibacterial agent, and they stimulate wound healing.

I think I can speak for everyone when I say: yeeech!