head lice

head lice Pediculus humanus capitis, parasitic insects found on the human scalp. They lay eggs on the hair shaft close to the root, and hatched lice stay mostly on the scalp. Head lice infection is very common and easily acquired by coming in close contact with someone who has head lice, infested clothing, or infested belongings. Preschool and elementary school children and their families are infested most often. Symptoms of head lice infestation include a tickling feeling of something moving in the hair, itching caused by an allergic reaction to the bites, irritability, and sores on the head caused by scratching. Although lice are very small, they can be seen on the scalp when they move. The eggs (nits) are easily seen on hair shafts. Treatment involves a combination of topical insecticidal medication and manual removal of all nits with a lice comb or the fingers.