Head Lice Summary Head lice are parasitic wingless insects. They live on people’s heads and feed on their blood. An adult louse is about the size of a sesame seed. The eggs, called nits, are even smaller – about the size of a knot in thread. Lice and nits are found on or near the scalp, most often at the neckline and behind the ears. Lice spread by close person-to-person contact. It is possible, but not common, to get lice by sharing personal belongings such as hats or hairbrushes. Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to do with getting head lice. Head lice do not spread disease. Symptoms are Tickling feeling in the hair Frequent itching Sores from scratching Irritability and difficulty sleeping. Head lice are most active in the dark. Treatment is recommended for people who have an active infestation of head lice. All household members and other close contacts should be checked and treated if necessary. Some experts also recommend treating anyone who shares a bed with an infested person. It is important to treat everyone at the same time. Centers for Disease Control and Prevention National Institute of Allergy and Infectious Diseases Find an Expert Centers for Disease Control and Prevention Centers for Disease Control and Prevention National Institute of Allergy and Infectious Diseases National Institute of Allergy and Infectious Diseases Start Here Head Lice American Academy of Dermatology Head Lice Centers for Disease Control and Prevention Head Lice American Academy of Family Physicians Head Lice: Frequently Asked Questions (FAQs) Centers for Disease Control and Prevention Array Head lice Treatments and Therapies Head Lice (Beyond the Basics) UpToDate Head Lice: Malathion Frequently Asked Questions Centers for Disease Control and Prevention Head Lice: Treatment Centers for Disease Control and Prevention Head Lice: Treatment Frequently Asked Questions (FAQs) Centers for Disease Control and Prevention Children Head Lice (For Parents) Nemours Foundation Head Lice (Pediculosis Capitis) Logical Images Head Lice: Information for Parents Centers for Disease Control and Prevention Lice Aren’t So Nice Nemours Foundation Diagnosis and Tests Head Lice: Diagnosis Centers for Disease Control and Prevention Head Lice: Disease Centers for Disease Control and Prevention Prevention and Risk Factors Head Lice: Prevention and Control Centers for Disease Control and Prevention Journal Articles Head Lice Patient Handouts Treating Head Lice Food and Drug Administration NIH MedlinePlus Magazine Understanding and Managing Head Lice
