Pinworm

Natural Habitat

The human large intestine (cecum, appendix, and ascending colon); eggs are often found in the perianal area or household environments.

Diet & Feeding

They feed on intestinal content, colonic bacteria, and potentially the host's epithelial cells.

Behavior Patterns

Gravid females migrate out of the anus at night to deposit thousands of eggs on the perianal skin, causing intense itching. This induces scratching, which leads to the transfer of eggs to hands and surfaces, facilitating transmission via the fecal-oral route.

Risks & Benefits

Risks include enterobiasis (pinworm infection), characterized by perianal itching, restless sleep, and irritability. While generally not dangerous, secondary bacterial infections can occur from scratching. They provide no known benefits to humans.

Identified on: 3/14/2026