Lice are tiny insects that commonly live on the scalp and cause itching. Learn how to spot the signs of head lice and eliminate them for good.


What Are Head Lice?

Lice are tiny, wingless insects that can infest humans, and the most common type is head lice. Head lice are the size of sesame seeds and are a brownish color. They live on the scalp where they glue their eggs (nits) to hair follicles, and after one to two weeks, the eggs hatch and the lice suck blood on the scalp for nourishment. The presence of the lice creates an allergic skin reaction, causing the scalp to get itchy.

Lice are contagious and can easily spread among children in close contact with each other, especially family members and classmates. Epidemics are common in day-care centers and schools with children between 3 and 12 years old. Head lice are usually transferred through head-to-head contact or by the sharing of hats, caps, clothes, hairbrushes, combs, and pillows. Although head lice seldom lead to complications, repeated scratching can cause secondary skin infections on the scalp, with a crusted, oozing rash, as well as swollen lymph nodes on the neck and throat. This is from repeated scratching of the scalp.

Symptoms and Signs of Head Lice

When a child has head lice, the most pronounced symptom is an itchy scalp, and the child may have sores and marks on the scalp from scratching. To see the lice and their eggs, it is often necessary to use a magnifying glass and a special lice comb, with closely spaced teeth. Head lice are usually found around the neck area, behind the ears, and on the top or crown of the head. Their oval-shaped, yellow-white eggs are found low down on the hair shaft, very close to the scalp.

How to Prevent Head Lice

Having a case of head lice is not a sign of poor hygiene and does not mean the child's house is unclean. Encourage your child not to exchange or borrow head coverings (hats, helmets, towels), hair accessories (barrettes, hair bands), and hairbrushes or combs from other children. Your child should not lie on bed linens or pillows that have been used by people with head lice. Examine your child's head closely every few days for a while if you have heard that one of his playmates has lice. Otherwise, if your child has a confirmed case of head lice, inform the day care or school immediately so that other children can be examined and treated.

Treatment for Head Lice

Contact your doctor immediately if you suspect your child has head lice. The doctor will recommend that your child's scalp be treated with medication in the form of a cream, shampoo, or lotion. Follow the treatment instructions and use as directed. Treatment works best when combined with using a special, closely spaced lice comb. The treatment should be repeated after 7 to 10 days because the eggs may have survived the first treatment. If you still see lice after treatment, consult your doctor again for another form of treatment, but do not use more than one remedy at a time. If the child has developed a secondary bacterial infection in the scalp, antibiotics may be needed.

Wash combs and hairbrushes in lice shampoo or hot, soapy water. Lice need to be around people to survive and they will starve if the clothes are not worn for a week, so remove the lice from clothes, hats, scarves, and other headgear. Wash all the garments in hot, soapy water and then put them in a dryer at a high setting.

Other family members and children should be examined actively for the infection, but only people who are truly infected by lice should be treated and, ideally, all infected persons should be treated at the same time to prevent a new outbreak. Pets cannot get head lice or spread infection. Because lice do not live long when away from people, extensive house cleaning generally is not necessary.

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