Head lice - two words that produce untold anxiety, fear, dread and shame for any parent. Are these worries justified? Should parents face humiliation from a scalp infected by a tiny bug named Pediculus humanus var. capitus?
The presence of head lice causes itchy scalps and may lead to poor sleep and irritability. The result of constant scratching frequently causes scalp infections that, in this era of resistant staph infection, can endanger health. In addition, children may become socially stigmatized when they are unnecessarily removed from schools that have no-nit policies.
A head lice infection is not associated with poor hygiene or an unclean environment. Lice pass from the head of one child to another's during ordinary play. While they may be transmitted by shared use of a comb or a pillowcase, the incidence of that is quite rare. Because lice must suck blood from a scalp at least every six hours, they quickly weaken and die in environments away from a host's head.
When should parents be concerned? If a child is constantly scratching his scalp, or if close relatives, classmates or playmates are diagnosed with an infestation, an inspection is warranted. A close inspection, in good light, may reveal tiny lice (the size of the head of a pin) moving in the hair or nits (eggs) tightly attached to the hair shaft near the scalp. If a parent or caregiver feels squeamish or unable to do this examination, a pediatrician or other experienced health-care provider can often locate lice missed on cursory examination.
Treatment at one time was quite simple and effective. Prescriptions were written for Lindane (Kwell) or Permethrine (Nix). Parents were told to use it once or twice, a week to 10 days apart, and to use a "nit comb" to groom the hair frequently. This therapy, however, is now inadequate. Lice have developed resistance to these drugs and products. In addition, we now know these medications have little effect on louse eggs, and soon after the last treatment, new larvae hatch to carry on infection.
Numerous other strategies have been used to treat lice infections. Head shaving is probably effective, as hair shafts are required for louse survival, but the practice is fashionably questionable for girls and for most elementary-school boys. Attempts to smother lice by coating the hair with peanut butter, mayonnaise, alcohol or vinegar prove unsuccessful, because it's nearly impossible to smother a louse.
There is a new combination prescription product on the market that contains malathion as the main ingredient. In the United States, where it is available mixed with alcohol and terpineol, it has proven very effective with no signs of resistance. It kills both nits and lice, and requires two applications, seven to nine days apart.
Some physicians believe that close household and school contacts of an infected child should also be treated since the treatment is safe and a diagnosis could be missed. Once treatment is documented, the student should be disease-free and able to return to school immediately. But if a case is missed, the disease can spread quickly and extensively.
Even though the louse does not live long off the scalp, a number of steps should be taken to limit spread and recurrence. Avoid sharing combs, brushes, hair bands, barrettes, scrunchies and other grooming tools. Wash stuffed animals, toys and bedding in hot water or, if not washable, place them in a dryer for 15 to 20 minutes to prevent the possible further spread of head lice.
Most importantly, don't be embarrassed or feel inadequate as this bug, like other infections, is passed from patient to patient regardless of good parenting. Though a nuisance, the infestation is not life-threatening and will go away with effective treatment.
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Dr. Edward Bailey is chief of pediatrics at NSMC North Shore Children's Hospital, on staff at Mass General Hospital for Children and a father of three. You can contact him at ebailey@aap.org.
