Human Lice (Head louse / Body louse)

Scientific Name: Pediculus humanus

Order & Family: Order: Psocodea. Family: Pediculidae.

Size: 2.0–3.0 mm (approximately the size of a sesame seed).

Human Lice (Head louse / Body louse)

Natural Habitat

Exclusively on the human body; head lice inhabit the hair and scalp, while body lice live in clothing and move to the skin to feed.

Diet & Feeding

Obligatory hematophages; they feed exclusively on human blood several times a day.

Behavior Patterns

They are wingless and cannot jump or fly, spreading through direct contact or shared personal items. They undergo hemimetabolous metamorphosis: egg (nit), nymph, and adult.

Risks & Benefits

Risks include intense itching, allergic reactions to saliva, and secondary skin infections from scratching. Body lice specifically can transmit serious diseases like epidemic typhus and trench fever. There are no known ecosystem benefits.

Identified on: 1/13/2026