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Head Lice

URL of this page: http://www.nlm.nih.gov/medlineplus/headlice.html

Also called: Also called: Pediculosis

Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult is called a louse and is about the size of a sesame seed. The eggs, called nits, are even smaller - almost like a dandruff flake. Lice and nits are easiest to detect at the neckline and behind the ears.

Head lice are extremely contagious. Close contact or sharing personal belongings, such as hats or hairbrushes, puts people at risk. Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to do with getting head lice.

Symptoms are

The most important step in treating head lice is to treat the person and other family members with medicine to kill the lice.

Centers for Disease Control and Prevention

Start Here Overviews Diagnosis/Symptoms Treatment Prevention/Screening Related Issues Clinical Trials Journal Articles
References and abstracts from MEDLINE/PubMed (National Library of Medicine)
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The primary NIH organization for research on Head Lice is the National Institute of Allergy and Infectious Diseases - http://www.niaid.nih.gov/

Head Lice - Multiple Languages - http://www.nlm.nih.gov/medlineplus/languages/headlice.html

Date last updated: July 16 2008
Topic last reviewed: June 16 2008