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 human clothing and bedding, only coming onto the skin to feed.

Diet & Feeding

Strictly hematophagous; they feed exclusively on human blood several times a day.

Behavior Patterns

They live and lay eggs (nits) in the seams of clothing and bedding rather than on the body. They are most common in crowded conditions where hygiene is poor and clothing is not regularly laundered.

Risks & Benefits

They are a significant public health risk as they can transmit serious diseases such as epidemic typhus, trench fever, and louse-borne relapsing fever. They cause intense itching and skin irritation (pediculosis corporis).

Identified on: 1/8/2026