Definition of Pinworms:

Pinworms are small worms that infect the intestines. They are common in children and easy to treat.

Causes, incidence, and risk factors:

Pinworms are the most common worm infection in the United States, primarily affecting school-age children. Pinworm eggs are spread directly from person to person or by touching bedding, food, or other items contaminated with the eggs.

Typically, children are infected by unknowingly touching pinworm eggs and putting their fingers in their mouths. The eggs are swallowed, and eventually hatch in the small intestine. The worms mature in the colon. Female worms then move to the child's anal area, especially at night, and deposit more eggs. This may cause intense itching and the area may even become infected. When the child scratches the itching anal area, the eggs can get under the child's fingernails and be transferred to other children, family members, and items in the house.