Pinworm

Natural Habitat

The human large intestine; they are found globally, frequently in children and crowded living conditions.

Diet & Feeding

They feed on host intestinal contents and colonic bacteria.

Behavior Patterns

Adult females migrate to the perianal area at night to lay eggs, which causes itching. The life cycle from egg ingestion to adult worm takes about 4 to 8 weeks.

Risks & Benefits

Risk: Causes enterobiasis, an infection characterized by intense anal itching, irritability, and disturbed sleep. Benefit: None to the host; they are purely parasitic.

Identified on: 3/28/2026