Body Louse
Scientific Name: Pediculus humanus humanus
Order & Family: Order: Psocodea (formerly Phthiraptera), Family: Pediculidae
Size: 2.3 mm to 3.6 mm (approximately the size of a sesame seed)
Natural Habitat
Found on humans, specifically living in the seams of clothing and bedding and moving to the skin only to feed.
Diet & Feeding
Obligate blood-feeders: they consume human blood several times a day.
Behavior Patterns
They lay their eggs (nits) in the seams of clothing. They are typically spread through prolonged close physical contact or sharing infested clothing/bedding. Unlike head lice, they are associated with crowded living conditions and infrequent laundering of clothes.
Risks & Benefits
Risks include intense itching, allergic reactions to bites, and secondary skin infections. They are significant vectors for dangerous diseases such as epidemic typhus, trench fever, and louse-borne relapsing fever. There are no ecological benefits to humans.
Identified on: 3/16/2026