As kids head back to school…
some facts you may need to know about head lice
Head lice can cause uncomfortable itching and embarrassment, but do not cause serious disease.
Head lice, or Pediculosis capitus, can occur at any age, but is most common in children three to twelve years old. Parents often know little about head lice, and receive conflicting and confusing advice about what to do. Here are the answers to the questions they usually have.
What are head lice?
Head lice, or Pediculus humanus capitus, are insects, which are obligate human parasites, in other words, they require humans to stay alive. They infest, feed, and breed on human bodies, chiefly the scalp.
What are the symptoms of head lice?
Itching is the primary symptom, resulting from an allergic reaction to the louse (singular) saliva injected into the skin during a bite. Sores on the skin can result due to scratching and secondary infection.
Are head lice dangerous?
Head lice can cause uncomfortable itching and embarrassment, but do not cause serious disease. (However, body lice, a related but different parasite, can transmit disease to humans.)
Are head lice contagious?
Head lice are spread by direct person-to-person contact. Lice cannot jump or fly between individuals. They survive less than twenty-four hours off the human body, so spread by contact with infected surfaces like bed- linens is possible but not likely.
How do I know if my child has head lice?
The diagnostic sign of head lice are white specks found attached to the hair, sometimes mistaken for dandruff. These are called nits and are the eggs laid by an adult louse. The adult louse lives at the base of the hair shafts or on the scalp, but can be difficult to see without bright light and magnification because it is only one eighth inch (3 millimeters) long. A physician should be consulted if the diagnosis is uncertain.
My child has head lice. How do I get rid of them?
Head lice are usually treated with topical medication. Because some of the eggs will survive treatment, a second course after seven to ten days is often necessary.
Most doctors recommend pyrethrin (Rid) or permethrin (Nix) as first line therapy, both available without a prescription. These solutions are applied to the scalp and hair, left on for at least ten minutes then rinsed off. They can be used in children over (2) two months old. No known adverse effects have been documented in women who are pregnant or nursing.
If either or both of these fail, a physician may prescribe an alternate drug, malathion. It is highly effective but potentially more toxic. After application, it is left on for eight to twelve hours before washing out. Unlike the two previous medications, malathion is not approved for use in children under (6) six years old.
An oral medication, ivermectin, can be effective in treating lice in a single dose. However, it is not FDA approved for this use and cannot be given to children weighing less than thirty-three pounds (15 kilograms).
Non-drug treatment can be used as an alternative to medication, but alone is not very effective. They are the only option in infants under two months, and can supplement use of the topical medications. Combing wet hair with a fine-tooth comb may remove nits.
Another method involves suffocating the adult louse by occlusion. About thirty to forty grams of petroleum jelly is applied to the hair and scalp and left on overnight. (A shower cap can be placed over the head to minimize the messiness.) This treatment can be repeated nightly as needed. Thorough and multiple washings with regular shampoo will remove the petroleum. This method is best for eyelash and eyebrow lice involvement.
What should be done about family and school contacts?
Because lice are spread only by direct person-to- person contact, household and school contacts need not be treated routinely unless they have shared a bed with the affected child. It is reasonable to inspect close contacts for the presence of lice and treat if found. It is not necessary or wise to bar the child from attending school during treatment.
How can I keep lice from coming back after treatment?
Adequate and correct use of the treatment medications is the first step in eradicating lice for good. The medicines must be applied to the hair and scalp thoroughly and left on long enough to be effective.
Lice may still be living in recently used bedding and clothing so a thorough washing in hot water, heated drying, or dry cleaning should be performed. Upholstered furniture, carpets, and car seats can be vacuumed. Wash combs and brushes in hot water.
Parents should teach their children not to share combs, brushes, or hats with other people. Some parents might want to check young children once a week for lice or just after situations where transmission might occur, such as camp or a sleepover.
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"As kids head back to school…
some facts you may need to know about head lice"
Dr. Aletha Oglesby practices family medicine at the Utica Park Clinic in Tulsa, Oklahoma. She has an interest in international health issues and has traveled overseas on numerous humanitarian medical trips....