Firstly, it is spelled "different".Secondly, an intestinal parasite populates the gastro-intestinal tract in humans and other animals. A parasite may be attached to an organism at any other location....
Yes, it feeds on the intestinal walls of the host.
It is also know that the worm leaves it's fecies or crap in the humans lower intestine and the human can occasionally throw it up.
Though I don't know exactly what you should do, I see a lot of intestinal parasite medications for fish in petstores liek PetSmart. I suggest you go look in there. There are several tablets that I...