Pinworm

Natural Habitat

Human gastrointestinal tract, primarily inhabiting the colon and rectum; eggs can be found in household dust and on surfaces.

Diet & Feeding

Absorbs nutrients from the host's intestinal contents.

Behavior Patterns

Nocturnal activity where gravid females migrate out of the anus to deposit eggs on the perianal skin, causing itching. Life cycle depends entirely on a human host.

Risks & Benefits

Risk: Causes enterobiasis, characterized by intense anal itching and potential secondary infections from scratching. No ecosystem benefits; exclusively a human parasite.

Identified on: 2/19/2026