Head lice are small parasitic insects that thrive in human hair by feeding on tiny amounts of blood from the scalp. An estimated six to 12 million infestations occur in the U.S. annually. It is particularly common among pre-school and elementary school children. Head lice do not transmit any diseases, but they are very contagious and can be very itchy. They are characterized by the combination of small red bumps and tiny white specks (also known as eggs or nits) on the bottom of hair closest to the skin (less than a quarter-inch from the scalp).
Head lice are visible to the naked eye. The eggs look like yellow, tan or brown dots on a hair. Live lice can also be seen crawling on the scalp. When the eggs hatch, they become nymphs (baby lice). Nymphs grow to adult lice within one or two weeks of hatching. An adult louse is about the size of a sesame seed. Lice feed on blood from the scalp several times a day. They can also survive up to two days off of the scalp.
Head lice are spread through head-to-head contact; by sharing clothing, linens, combs, brushes, hats and other personal products; or by lying on upholstered furniture or beds of an infected person. You can determine if your child has head lice by parting the child's hair and looking for nits or lice, particularly around the ears and nape of the neck. If one member of your family is diagnosed with head lice, you'll need to check on every member of the same household.
Application of a medicated cream rinse or shampoo is usually effective treatment for head and/or pubic lice. Specific instructions need to be followed. Discuss this with your physician. Examples of medicated cream rinses or shampoos include the following: