TUESDAY, May 8 (HealthScout) -- Just because your kid's got a head full of lice eggs doesn't mean that child should be sent home from school, says a study from the Centers for Disease Control and Prevention (CDC).
Most nits (lice eggs) more than one-quarter inch away from the scalp, won't grow into lice, and most kids with hair nits will not become infested with lice, the researchers say. Automatically sending children home from school because of nits is overkill, they say. Nits are just the casings for lice eggs; some contain developing embryos; others are just empty shells.
The CDC experts says training school personnel to keep screening children for nits and lice is better than sending the kids with nits home.
"I have a number of documents supporting the fact that nits that are further than one-quarter inch from the scalp do not have the proper conditions for incubation and hatching," says Mary Shepherd, a medical information specialist with the CDC in Atlanta. "And the nits [with embryos] that fall off usually die very quickly, so they are not a threat. Very often, the people who are doing these lice inspections in children misidentify the nits because they look like pieces of dandruff or a piece of skin from the scalp."
To see if kids with nits developed lice, the CDC investigators screened 1,729 children in two Atlanta, Ga., elementary schools. Twenty-eight children (less than 2 percent) were infested with lice, while 63, or less than 4 percent, had nits but no lice.
After two weeks, only nine of the 63 children with only nits developed head lice, the investigators say. Having nits near the scalp turned out to be a risk factor for lice infestation, as did having greater than five nits within one-quarter inch of the scalp.
The distance is important because it indicates the age of the nits, say the CDC researchers. Eggs are laid and attached to hair close to its base. However, based on the growth rate of human hair, nits more than one-quarter inch from the scalp probably are too old to hatch and are just casings that won't turn into lice.
The findings are in the May issue of Pediatrics.
About two-thirds of all U.S. school systems have no-nit policies that send children home for treatment and only allow them back in school after all traces of the lice are gone. The study only suggests that school personnel be better trained to reinspect students to make sure nits do not develop into lice because "the CDC just does not have that kind of jurisdiction," Shepherd says. "That's ultimately up to the local school systems and health departments."
Lice is common among children. An estimated 6 million to 12 million cases are reported worldwide each year, says the CDC. Head lice are one of three types that infest people. The insects (about one-tenth to one-eighth of an inch long) make their home in human hair and feed on human blood. Head lice multiply rapidly, laying small grayish-colored, oval-shaped eggs or nits, which they glue to the base of the hair.
Head lice rarely cause harm, and they are not known to transmit germs. They are spread by either direct head-to-head contact with an infested person, or shared combs, hats and other hair accessories, according to the Harvard School of Public Health. They may also stay on bedding or upholstered furniture for brief periods.
Getting rid of school no-nit policies is appropriate, says the National Association of School Nurses. "A no-nit policy is probably not necessary, and it keeps kids out of school so they can't benefit from their education," says Judith Harrigan, the association's training coordinator in Castle Rock, Colo. "Having nits alone and not letting the kids go to school is not necessarily the best course action."
But the no-nits rule will remain in schools in Johnston County, N.C.
"It would be my recommendation for our school system to continue a no-nit policy," says Linda Beckett, the school nursing coordinator for the county school system. "Our recurring cases of head lice have been reduced since we initiated a no-nit policy." Beckett says that Johnston County started a no-nit policy three to four years ago because they had too many recurring cases of head lice.
Beckett rejects the notion that sending a child home for treatment is "excessive." "Honestly and truthfully, it doesn't affect them for weeks and weeks if the parent treats the problem properly. In our policy, a child is excused for up to three days, and rarely does a child need three days before they come back cured."
Beckett says the biggest problem is not the kids. "Parents are not following or are inadequately following instructions to get rid of head lice. That was our problem. But the people at the CDC have to realize that we are dealing with dual-income as well as single-parent families with multiple children, and then there is a time factor involved in taking care of this problem."
"The real issue with eradicating nits, is infestation in a house, not on a child's head," she says.
"Thankfully, parents and health professionals do not need permission or scientific studies to appreciate the importance of keeping their children lice and nit free," says Deborah Altschuler, President of the National Pediculosis Association in Newton, Mass.
What To Do
For more information on lice, see the Harvard School of Public Health or the CDC.
And read these other HealthScout stories on lice.
