About Lice

Key points

  • Lice are parasitic insects found on people's heads and bodies.
  • Lice spread by close person-to-person contact.
  • The three types of lice affecting humans are head, body, and pubic.
  • Both over the counter and prescription medications can treat lice.
Head Louse

Overview

Lice are parasites, or insects, found on people's heads and bodies, including the pubic area. Human lice survive by feeding on human blood. Infestation or infested person means that a person has lice.

Types

There are different types of lice on areas of the body. The three types of lice that live on humans are:

  • Head louse (Pediculus humanus capitis)
  • Body or clothes louse (Pediculus humanus corporis)
  • Pubic or "crab" louse (Pthirus pubis)

Only the body louse can spread disease.

How it spreads

You get lice (head, body, and pubic) from close person-to-person contact with someone who has a lice infestation. Dogs, cats, and other pets do not carry or spread human lice. Lice move by crawling; they cannot hop or fly.

Treatment

You can treat lice infestations with both over-the-counter and prescription medications.