Head Louse

Scientific Name: Pediculus humanus capitis

Order & Family: Order: Psocodea; Family: Pediculidae

Size: 2.1 to 3.3 millimeters

Head Louse

Natural Habitat

Human scalp and hair

Diet & Feeding

Obligate blood feeder on humans

Behavior Patterns

Crawl between hosts via direct head-to-head contact; attach eggs (nits) to hair shafts near the scalp.

Risks & Benefits

Cause itching and scalp irritation due to allergic reactions to saliva; do not transmit diseases, though secondary bacterial infections can occur from scratching.

Identified on: 6/3/2026