Human Head Louse (Nits)
Scientific Name: Pediculus humanus capitis
Order & Family: Order: Psocodea; Family: Pediculidae
Size: Nits are approximately 0.8 mm long; adults are 2-3 mm long (about the size of a sesame seed).
Natural Habitat
Exclusively on the human scalp and hair; nits are firmly glued to hair shafts close to the scalp for warmth.
Diet & Feeding
Strictly hematophagous; they feed on human blood several times a day.
Behavior Patterns
They cannot fly or jump; they move by crawling. Nits take about 7-10 days to hatch. Infestations spread primarily through direct head-to-head contact.
Risks & Benefits
Risks include intense itching, scalp irritation, and potential secondary bacterial infections from scratching. They do not spread disease. No ecosystem benefits.
Identified on: 3/7/2026