What Are They?
Head lice are tiny insects that live primarily on the head and scalp. They should not be confused with body lice, which may be found in clothing and bedding as well as on the body, or crab lice, which infest the pubic area. Head lice are found only on humans and should not be confused with fleas, which may be found on dogs, cats and other pets.
They hatch from small eggs, called nits (appearing as tiny white or dark ovals), which are firmly attached to the individual hairs near the scalp and cannot be easily moved up or down the hair (as could specks of dandruff.) Nits may be found throughout the hair but are most often located at the back of the scalp, behind the ears, and on the top of the head. The eggs hatch in about 10 days, with new lice reaching adulthood in about two weeks. The female louse is about the size of a sesame seed, can live for 20 to 30 days, and can lay about six eggs a day. The lice, generally found on top of the head, live by biting and sucking blood from the scalp. Lice can survive for more than 24 hours between feedings and can do so off the body.
What Are the Symptoms?
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 viewed with suspicion. Occasionally, red bite marks and scratch marks can be seen on the scalp and neck. In cases of severe infestation, a secondary bacterial infection can occur causing oozing or crusting. Swollen neck glands can also result.
Diagnosis is usually made by finding nits, which are tiny, pearl gray and oval-shaped specks attached to the hair near the scalp. Use a magnifying glass and natural light when you search for them on the hair at the back of the neck, behind the ears and on the top of the head. Live lice move quickly and are hard to see. Most children with head lice will be treated with a medicated shampoo, rinse or lotion developed specifically for head lice. These treatments are insecticides and may be toxic if not used as recommended. Do not treat unless there is a clear diagnosis of head lice. Effective treatment includes removal of all nits and environmental cleaning.
Who Gets Them and How?
Head lice are not a sign of unclean people or homes. They can occur regardless of age, gender, race or socioeconomic status. Anyone who has close contact with an infested person or shares personal items can become infested. Lice are spread only by crawling from person to person (head-to-head contact) or onto shared personal items such as combs, brushes, head coverings, clothing, bedding, towels, etc.
When Should People with this Illness Be Excluded?
Children should not be excluded or sent home early from childcare or school because of head lice. Parents of affected children should be notified and informed that their child must be properly treated before returning to school the next day. Other close contacts should be checked to determine if there are other cases. If your facility is having a problem with head lice, you should conduct morning “head checks” before the children socialize together. After proper application of an appropriate treatment, re-infestation of children from an untreated infested contact is more common than treatment failure.
“No-nit” policies requiring that children be free of nits before they return to child care or school have not been effective in controlling head lice transmission and are not recommended. Regardless of the policy, to ensure successful treatment the children need to be checked for new nits for ten days after therapy.
How Can I Limit the Spread?
To prevent the spread of head lice when a case occurs in the child care setting:
- Caregivers and parents should learn to recognize nits and regularly check children’s hair when there is a known case of head lice in the facility. Because almost all facilities will have outbreaks of head lice periodically, and because the anxiety produced by head lice is far greater than their threat to health, this is a prime area for preventive, anticipatory, parent information.
- A well-organized and prompt response to the first few cases can prevent a widespread problem.
- On the same day, screen all children in the classroom or group and any siblings in other classrooms for adult lice or nits. Notify parents of children found to have head lice or nits. Simultaneous treatment of all infested children is necessary to prevent spread back to previously treated children.
- Educate parents regarding the importance of following through with lice detection and management recommendations at home, and notifying the facility if head lice have been found.
- Although head lice are not able to survive off humans for more than 24-48 hours, many persons recommend washing clothes (including hats and scarves) and bedding in very hot water, and vacuuming carpets and upholstered furniture in rooms used by person infested with these insects. Combs and hair brushes may be soaked in hot (65º C) water for at least one hour. Flea bombs and other environmental insecticides are not effective against head lice.
