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

Found on human bodies and primarily lives in the seams and folds of clothing/bedding, crawling onto the skin only to feed.

Diet & Feeding

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

Behavior Patterns

They are highly dependent on human warmth and blood; their entire life cycle occurs on or near the host. Females lay eggs (nits) in the seams of clothing.

Risks & Benefits

Risks include intense itching, allergic reactions, and the potential transmission of dangerous diseases such as epidemic typhus, trench fever, and louse-borne relapsing fever.

Identified on: 6/3/2026