What should you know about CDC head lice?

Lice are crawling insects that live close to the scalp; their eggs, called nits, are attached firmly to individual hairs. An itchy scalp is common, although a newly affected person may have little or no itching at first. Scratching can leave small sores and may irritate the skin. Head lice do not jump or fly, and finding a nit alone does not always prove that it is viable, so an active crawling louse is the clearest sign.

Use a bright light and a fine-toothed detection comb on wet, conditioned hair, working in small sections from the scalp outward. If live lice are found, follow the product instructions exactly; some treatments need a repeat application because eggs can survive the first treatment. Wash or heat-dry recently used pillowcases, towels, hats and clothing, and soak combs and brushes in hot water. Avoid sharing these items and check household members, especially anyone with close head contact. See Head Lice Treatment for options and technique.

Arrange a GP Consultation if you cannot confirm what you have found, treatment has not cleared live lice, or scratching has caused painful, crusted or oozing areas. Seek urgent help for facial swelling, breathing difficulty or widespread blistering after a lice product.

Ask whether live lice are present, which treatment suits the person's age and scalp, when it should be repeated, and how to manage persistent itch or broken skin.