Human Head Louse
Scientific Name: Pediculus humanus capitis
Order & Family: Order: Psocodea (formerly Phthiraptera), Family: Pediculidae
Size: 2 to 3 mm in length (roughly the size of a sesame seed).
Natural Habitat
The scalp and hair of human beings; most common in hair around the ears and at the nape of the neck.
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. They lay eggs (nits) near the base of the hair shaft. They cannot survive for more than about 24 to 48 hours away from a human host.
Risks & Benefits
Risks include intense itching (allergic reaction to saliva), sores from scratching, and secondary bacterial skin infections. They are not known to spread diseases. There are no known benefits to humans or the ecosystem.
Identified on: 3/12/2026