Head Louse

Natural Habitat

The human scalp and hair, most commonly found behind the ears and near the neckline at the back of the head.

Diet & Feeding

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

Behavior Patterns

They are wingless and cannot jump or fly; they move by crawling. Eggs (nits) are glued to hair shafts. They require a human host to survive and typically die within 24–48 hours if they fall off.

Risks & Benefits

They do not spread disease. The main risk is intense itching (pruritus) caused by an allergic reaction to their saliva, which can lead to secondary skin infections from scratching. They provide no known ecosystem benefits.

Identified on: 4/25/2026