Pinworm

Natural Habitat

Human large intestine (caecum and colon), often migrating to the perianal area

Diet & Feeding

Intestinal contents and epithelial cells of the human host

Behavior Patterns

Adult females migrate to the perianal area at night to lay thousands of eggs, which causes itching. Eggs are transmitted via the fecal-oral route through contaminated hands, surfaces, or dust.

Risks & Benefits

Causes enterobiasis, characterized by intense anal itching (pruritus ani), restlessness, and insomnia. While not life-threatening, it is highly contagious within households but provides no ecosystem benefits.

Identified on: 5/26/2026