Pinworm

The human gastrointestinal tract, primarily the large intestine and rectum

Content of the human intestine and digestive matter

At night, gravid females migrate to the perianal area to lay thousands of eggs, which can cause intense itching (pruritus ani).

Causes enterobiasis infection. While typically not dangerous, it leads to discomfort, itching, and sleeplessness; it is highly contagious through ingestion of microscopic eggs.