Louse (Head Louse or Body Louse)
Pediculus humanus capitis (Head Louse) or Pediculus humanus humanus (Body Louse)
- Order & Family
- Order: Psocodea (formerly Phthiraptera); Family: Pediculidae
- Size
- 2 to 3 millimeters long (about the size of a sesame seed).
Natural Habitat
Exclusively on the human body; head lice are found on the scalp hair, while body lice live in clothing and bedding but move to the skin to feed.
Diet & Feeding
Hematophagous (feed exclusively on human blood several times a day).
Behavior Patterns
They are obligate parasites that cannot fly or jump. They move by crawling rapidly along hair shafts using claw-like legs specialized for grasping. They lay eggs (nits) glued firmly to the base of hair shafts.
Risks & Benefits
Risks: They cause intense itching (pruritus) and social stigma. Scratching can lead to secondary bacterial skin infections. Body lice (but not head lice) are vectors for diseases like typhus, trench fever, and relapsing fever. Benefits: None known to humans.