Head Lice

Fact Sheet Pediculosis Capitus (Head Lice)

Head lice are tiny insects that live only on people’s scalps and hair. Head lice hatch from small eggs, called nits, that are firmly attached to individual hairs near the scalp and cannot be easily moved up or down the hair shaft (as could specks of dandruff or hair casings). Nits may be found throughout the hair, but are most often located at the back of the scalp, behind the ears, and at the crown of the head. Eggs hatch in about ten days, with new lice reaching adulthood in about two weeks. The female louse, about the size of a sesame seed, typically lives for twenty to thirty days and lays about six eggs a day. Lice live by biting and sucking blood from the scalp. Lice can survive off the body although generally not for longer than forty-eight hours.

The major symptom of head lice is itching caused by the bite of the louse. Persistent scratching of the head and back of the neck should be cause for concern. Red bite marks and scratch marks may be observed on the scalp and neck. A secondary bacterial infection can occur causing oozing or crusting. Swollen neck glands may also develop.

Head lice should not be considered a sign of unclean individuals or homes. They may affect individuals of any age or gender. Anyone who has close contact with an infested individual or shares personal items can become infested. Lice are spread only when they crawl from person to person directly or crawl onto shared personal items, such as combs, brushes, head coverings, clothing, bedding or towels. They cannot hop, jump or fly. An infested individual can transmit head lice to others continuously until undergoing treatment to kill the insects and eggs.

Diagnosis is usually made be detecting nits, tiny pearl gray, oval shaped specks attached to the hair near the scalp. In some cases, with close inspection, live lice may be seen moving on the scalp or in the hair close to the scalp.

Treatment consists of getting rid of the lice from infested individuals, their surroundings and their personal items. All household members and individuals with close contact should be examined for lice and, if necessary, treated with one of the recommended shampoos or hair rinses. Pyrethrin products, available over-the-counter, are often recommended for treatment.
Treatment includes shampooing or rinsing the hair with medicine. The procedure is best done over a sink in order to limit the area of the body coming in contact with the shampoo since it does contain some toxins.

1. Before applying treatment, remove all clothing from the waist up.

2. Apply lice medicine, also called pediculicide according to label instructions. If your child has extra long hair, you may need to use a second bottle.  WARNING: Do not use a creme rinse or combination shampoo/conditioner before using lice medicine. Do not re-wash hair for 1-2 days after treatment.

3. Have the infested person put on clean clothing after treatment.

4. If some live lice are still found 8-12 hours after treatment, but are moving more slowly than before, do not retreat. Comb dead and remaining live lice out of the hair. The medicine sometimes takes longer to kill the lice.

5. If no dead lice are found 8-12 hours after treatment and lice seem as active as before, the medicine may not be working. See your health care provider for a different medication and follow their treatment instructions.

6. A nit comb should be used to remove nits and lice from the hair shaft. Alternatively, the nit can be removed by sliding it off the hair shaft between your fingernails or by cutting the hair strand above the nit. All nits removed should be placed in a sealable plastic bag for disposal.

7. After treatment, check hair every day and use a nit comb to remove any nits or lice you see.

8. Retreat in 7-10 days.

9. Check all treated persons for 2-3 weeks after you think that all lice and nits are gone.

1. Machine wash all washable and possibly infested items in hot water. (130?) Dry them in a hot dryer.
2. Put non-washable items (furry toys, pillows) in a hot dryer for at least 20 minutes or dry clean them.
3. Place items that cannot be washed or dried in a tightly sealed plastic bag for two weeks.
4. Soak combs, brushes and hair products in hot soapy water for 10 minutes, or wash them with a shampoo approved to kill lice.
5. Thoroughly vacuum rugs, upholstered furniture, car seats and mattresses.
6. DO NOT use insecticide sprays or “bombs” in an attempt to stop the spread because they are ineffective and may be harmful to people and animals.


Individuals found to have an active case of head lice should be treated as soon as possible. Parents will be notified and dismissal will then be as timely as possible. Students will be allowed to return to school after:
1. They have been treated with a recommended product that kills lice.
2. They have had as many nits as possible removed.
3. They have had contact items cleaned and stored.
4. They have been checked by the school nurse.

PLEASE NOTE: It is the responsibility of parents to inspect the child’s head daily for at least two weeks. The School Nurse is available to assist parents with inspection and identification of lice or nits at any time.

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