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What are head lice?

Head lice are tiny crawling insects that live in a person’s head hair. The lice feed on blood sucked from the scalp and lay eggs—called nits—that firmly attach to the hair shafts. Infestation with head lice is also called pediculosis.

How common are head lice?

Head lice infestation is common, affecting 6 million to 12 million people each year. Lice are most common in school children, who are more likely to have close contact and to share combs, brushes and other objects. Head lice are more common in girls than in boys and are more common in Caucasians than in African-Americans. Anyone can get head lice. It is not a sign that a person is unclean.

What are the symptoms of head lice?

The most common symptom of head lice is itching, especially in the back of the head and neck and near the ears—areas where lice are more likely to live. Intense scratching can break the skin of the scalp and can lead to open sores and infection. However, it may take as long as two to three weeks after lice infestation for itching to begin.

How does a person get head lice?

Head lice spread by direct head to head contact and by sharing items — including combs, brushes, scarves and hats — with an infected person.