Louse (likely human head louse)

Scientific Name: Pediculus humanus capitis

Order & Family: Order: Psocodea (formerly Phthiraptera), Family: Pediculidae

Size: 2-3 mm (roughly the size of a sesame seed)

Louse (likely human head louse)

Natural Habitat

Exclusively inhabits the human scalp and hair, clinging to individual hair shafts; survives only vertically close to a host.

Diet & Feeding

Obligate hematophagy (feeds exclusively on human blood several times a day).

Behavior Patterns

Wingless insects that cannot jump or fly; they move by crawling from hair to hair. They lay eggs (nits) glued firmly to the base of hair shafts near the scalp for warmth.

Risks & Benefits

Risks include intense itching (allergic reaction to saliva), skin irritation, and possible secondary bacterial infections from scratching. Unlike body lice, head lice are not known to transmit systemic diseases.

Identified on: 1/13/2026