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Head lice

A parasitic disease
What is it?
Photo of Head licePhoto credit: CDC/ Dr. Dennis D. Juranek

Parasitic insects, head lice live in the hair and scalp of humans and feed on our blood. Some 6 to 12 million people worldwide get head lice each year. Head lice can infest anyone, regardless of personal hygiene. Young children and their families are most at risk.

How do I avoid it?

Avoid physical contact with anyone who has lice. Do not share personal items like hats, clothes, towels, brushes and combs. Each person should keep their items separate. If you do share, wash the item before using. Getting rid of head lice requires treating everyone in the infected household. Lice-killing medicine is available over-the-counter or by prescription. Check the scalp for several weeks until all lice and eggs are gone.

What are the symptoms?

Itching caused by an allergic reaction to the lice bites is one of the first signs of infection. Sores may develop from frequent head scratching. To confirm the presence of head lice, look closely at the hair and scalp. Adults are difficult to see, but the eggs or nits appear as small, yellowish-white droplets ìgluedî to the base of hair shafts.

How do I get it?

Head lice spread easily from person to person by direct contact. Lice can be transferred from one infected child to another during play at school or at home. People can also get head lice by using infested objects, such as combs, clothing or furniture. Pets do not spread lice to humans.

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