Head Louse

Natural Habitat

The scalp and hair of humans; they cannot survive long away from a human host.

Diet & Feeding

Hematophagous; they feed exclusively on human blood several times a day.

Behavior Patterns

Head lice are wingless parasites that crawl but cannot jump or fly. They attach their eggs (nits) firmly to the base of hair shafts. They spread primarily through direct head-to-head contact.

Risks & Benefits

Risks: Causes intense itching (pruritus due to an allergic reaction to saliva), scalp irritation, and sleep disruption. Secondary bacterial infections can occur from scratching. No environmental benefits as they are obligate parasites.

Identified on: 2/10/2026