Lice are parasites known as Pediculus humanus capitis. They are about 2-4 mm long and when they hatch they leave empty sacs of chitin sticking to the shafts of hairs, known as nits. The live lice require human tissue to live and can't survive after 24 hours without a "meal". Head lice causes severe itching of the scalp. Usually the transmission occurs directly from one head to the other by close contact. Sometimes shared combs and brushes which have human hair cells in the bristles from vigorous brushing can keep lice alive long enough to be transferred to others. A nit can't be easily removed or knocked off the shaft.

Because of the itching and the subsequent scratching some children develop infections of the scalp and this can result in lymph node enlargement and hair loss. For unclear reasons lice are rarely seen but the nits are commonly found in the hairline at the nape of the neck and above the ears. Sometimes a secondary dermatitis develops on the neck and earlobes and this is generally treatable by treating the lice and using topical steroids to quiet the itch. The treatment of choice is permethrin 1% cream rinse (NIX) applied for 10 minutes with a repeat application in 7-10 days. All household members should be treated at the same time. Nits can be removed with a fine- toothed comb after a 1;1 vinegar-water rinse. Clothing and bed linens should be laundered in very hot water or dry cleaned and brushes and combs should be thrown away or washed with NIX for 15 minutes and then boiled.

Head lice outbreaks occur every Fall in schools and there is usually a tremendous outcry from parents and administrators to remediate the situation. The best way to handle these outbreaks is to insist on school wide education regarding controlling the infestation when it occurs and then frequent and thorough head checks for new cases. Description Lice are parasites known as Pediculus humanus capitis. They are about 2-4mm long and when they hatch they leave empty sacs of chitin sticking to the shafts of hairs, known as nits.

How it is spread

Live lice require human tissue to live and can't survive after 24 hours without feeding. Usually transmission occurs directly from one head to the other by close contact. Sometimes shared combs and brushes which have human hair cells in the bristles from vigorous brushing can keep lice alive long enough to be transferred to others days later.

Course of Illness

Head lice causes severe itching of the scalp and therefore some children develop infection and enlargement of nearby lymph glands and even hair loss. Sometimes a secondary dermatitis develops in response to the bites and adds to the general itching and discomfort. Untreated outbreaks can spread for months and rarely resolve spontaneously unless severe measures such as head shaving is undertaken. For this reason early treatment with a pediculocide shampoo is essential.

Treatment

The treatment of choice is permethrin 1% usually in a cream rinse formula applied for 10 minutes and reapplied in 3-10 days depending on whether new nits appear in that time. All household members and close contacts should also be treated and linens should be laundered in very hot water or dry cleaned. Brushes and combs need treating with permethrin as well and then boiling. Nits may be more easily removed with a fine toothed comb after a 1:1 vinegar-water rinse. In cases of secondary rash, topical steroid s can be applied to reduce the itch.

When to seek help

Bringing your child with head lice to the doctor is a very unpopular thing to do. If there is no response to usual treatment or your child has a fever in association with an oozing scalp rash, your pediatrician may need to examine your child to rule out other infections such as impetigo. Call ahead to the office so that they are prepared with an isolation room when you arrive in order to prevent spread in the waiting room.