Threadworm
Threadworms are very small, they infect intestines of humans. They range from 3 to 15 millimeters long. They infect little children, the most common parasite in children in the U.S.The threadworm effects mostly children throughout the world. The eggs are caught by ingesting them, and then the eggs hatch. The worms grow and infect your bowels, usually not noticeable.
They are structurally the same as the roundworm, the round worms can be much larger than the threadworm. The threadworm is white and very small and skinny, becoming hard to study fully.