Body Louse

Scientific Name: Pediculus humanus humanus

Order & Family: Order: Psocodea (formerly Phthiraptera), Family: Pediculidae

Size: 2.3 to 3.6 millimeters (about the size of a sesame seed).

Body Louse

Natural Habitat

Typically found in the clothing and bedding of infested humans; they move to the skin to feed.

Diet & Feeding

Strict blood-feeders (obligate hematophages) that feed on human blood several times a day.

Behavior Patterns

They live and lay eggs (nits) in the seams of clothing and only crawl onto the skin to feed. They are most common in crowded living conditions where hygiene is poor and clothing is not regularly laundered.

Risks & Benefits

Risks: Can cause intense itching and skin rashes (pediculosis). They are significant vectors for serious diseases such as epidemic typhus, trench fever, and louse-borne relapsing fever. Benefits: None.

Identified on: 12/27/2025