These worms live in the human intestines by attaching to the intestine wall and feeding off of the nutrients there. These worms can live for years and can reach up to 60 feet in length if not killed. The eggs of these worms get passed on to the next host when they eat foods that are contaminated with eggs from feces. Since pigs and cows can also be infected, the meats of these animals can sometimes pass on the worm if not cooked enough. The worms can sometimes migrate through the intestines to other areas of the body where they cause anything from belly problems to seizures.