Human Head Louse
Scientific Name: Pediculus humanus capitis
Order & Family: Order: Psocodea, Family: Pediculidae
Size: Adults: 2–3 mm (about the size of a sesame seed). Nits (eggs): 0.8 mm.
Natural Habitat
The human scalp, primarily near the hairline, behind the ears, and at the nape of the neck.
Diet & Feeding
Obligate hematophagous; they feed exclusively on human blood multiple times a day.
Behavior Patterns
They are wingless and cannot jump or fly; they move by crawling. They glue their eggs (nits) to hair shafts near the scalp. They cannot survive more than 24-48 hours away from a human host.
Risks & Benefits
Risks include intense itching, scalp irritation, and secondary bacterial infections from scratching. They do not transmit diseases. There are no ecological benefits known to humans.
Identified on: 3/7/2026