Body Louse / Head Louse (Nits and Adults)
Scientific Name: Pediculus humanus
Order & Family: Order: Psocodea (formerly Phthiraptera), Family: Pediculidae
Size: 2.0–3.5 mm (adults), nits are about 0.8 mm
Natural Habitat
Human body hair and clothing; head lice reside specifically on the scalp and hair, while body lice live in clothing seams and move to the skin to feed.
Diet & Feeding
Obligate hematophages; they feed exclusively on human blood several times a day.
Behavior Patterns
They are wingless and crawl instead of jumping. Females glue 'nits' (eggs) to hair shafts or clothing fibers. They cannot survive for more than 24-48 hours away from a human host.
Risks & Benefits
Cause intense itching (pediculosis) and skin irritation. While head lice do not spread disease, body lice can transmit epidemic typhus, trench fever, and louse-borne relapsing fever. They have no ecosystem benefits.
Identified on: 1/11/2026