Head Lice Infestation
(Pediculosis)

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Head lice facts

  • Head lice are parasites that are found on human heads. The word lice is plural for louse.
  • Head lice are spread by personal contact or the sharing of combs, brushes, caps, and other clothing.
  • Head lice are a common problem with preschool and schoolchildren.
  • Head lice cause a tickling feeling of something moving in the hair, itching, and sores on the head.
  • The affected individual, family members also infected, and the home all should be treated.
  • Remember: one head louse + one head louse = two head lice = the beginning of a head-lice infection.
  • Very young children should be evaluated by a health-care professional before beginning medications.

What are head lice?

Head lice are parasites that can be found on the heads of people. Infection with head lice is called pediculosis. (The head louse, Pediculus humanus capitis, is different from the lice that cause body and pubic-hair infections.)

How common is head lice infestation?

Head lice infection is very common. It has been estimated that up to one in every 10 children in school acquires head lice at some time.

Who is at risk for getting head lice?

Anyone who comes in close contact with someone who already has head lice, or even their contaminated clothing and other belongings, is at risk for acquiring head lice. So it is easy to transmit head lice from one person to another. Preschool and elementary-school children (3-10 years of age) and their families are infected most often. Girls contract head lice more often than boys, and women contract more head lice than men. African-Americans rarely acquire head lice.

Medically Reviewed by a Doctor on 7/18/2014

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Head Lice - Describe Your Experience Question: Please describe your experience with head lice infestation (pediculosis).
Head Lice - Treatments Question: What treatment was effective for your head lice?
Head Lice - Signs and Symptoms Question: What were the signs and symptoms experienced with head lice in you or a relative?
Head Lice - Prevention Question: What methods have you used to prevent head lice infestation? What do you tell your children?
Head Lice - Home Remedies Question: Please share effective home remedies for head lice. Who in your household was treated?

Head Lice Symptoms

Although itching may be a sign of a lice infestation, most often individuals are asymptomatic. Keep in mind that although the only reliable sign of an infestation is the presence of a live louse or nymph (juvenile louse), the presence of nits may be a sign that there is or has been an active infestation.