Human Head Louse

Scientific Name: Pediculus humanus capitis

Order & Family: Phthiraptera: Pediculidae

Size: 2.0 mm to 3.0 mm (roughly the size of a sesame seed).

Human Head Louse

Natural Habitat

Human scalp and hair, most commonly found near the nape of the neck and around the ears.

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 from hair to hair. They lay eggs called nits which are glued to hair shafts close to the scalp.

Risks & Benefits

While they cause intense itching and social distress, they are not known to transmit diseases. Excessive scratching can lead to secondary bacterial skin infections.

Identified on: 5/19/2026