Head lice

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Head lice

Nit on human hair

Lice, head - nits in the hair with close-up

Head louse emerging from egg

Head louse, male

Head louse - female

Head louse infestation - scalp

Head lice

Definition:

Head lice are tiny insects that live on the scalp. They can be spread by close contact with other people.

These lice only live in hair and occasionally eyebrows and eyelashes.

See also:

Body lice

Pubic lice

Alternative Names:

Lice - head; Nits; Pediculosis capitis - head lice

Causes, incidence, and risk factors:

Head lice infect hair on the head. They are easiest to see on the neck and over the ears. Tiny eggs on the hair look like flakes of dandruff . However, innstead of flaking off the scalp, they stay put.

Head lice can survive on clothing, carpets, or bedding for up to 10 days. Their eggs can live for more than 2 weeks.

Head lice spread easily. You can get head lice when you come in close contact with an infested person or touch their clothing or bedding. Head lice are more common in close, overcrowded living conditions. Lice spread easily among school children.

Having head lice is NOT an indicator of poor hygiene or low social status.

Head lice causes intense itching, but does not lead to a serious medical problem. Unlike body lice, head lice never carry or spread diseases.

References:

Long SS, Pickering LK, Prober, CG, eds. Principles and Practice of Pediatric Infectious Diseases. 2nd Ed. New York, NY: Churchill Livingstone, 2003.

Mandell GL, Bennett JE, Dolin R, eds. Principles of Infectious Diseases. 5^th Ed. New York, NY: Churchill Livingstone, 2000:2972-2973.

Goetz CG, Pappert EJ. Textbook of Clinical Neurology. 2^nd Ed. Philadelphia, PA: Saunders; 2003.

Review Date: 3/17/2006
Reviewed By: John Goldenring, MD, MPH, Department of Pediatrics, Children's Hospital, San Diego, CA. Review provided by VeriMed Healthcare Network.

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