Where the Wild Things Are : Never mind that a case of head lice is considered harmless. Experts agree that the hardy bloodsuckers are devilishly tricky to get rid of.

Head lice are wondrous beasts. Consider their claws: perfectly formed for clutching hair and swinging slim louse bodies from strand to shining strand. Consider their keen sense of smell, temperature, gravity and more: Not for them Rover’s hide, nor Kittycakes’ pelt, nor other hairy spots upon the human host. Put a louse on a person and it creeps its way up till it reaches that forested pinnacle and sinks its fangs, if not a flag, into the fleshy floor.

Some people are drawn to lice. Scientists seek them out, teasing through fur and feathers of everything from mammals in Missouri to ospreys in Ontario and diligently cataloging every little beastie they find. They’ve even ventured into jails to harvest lice off people’s heads so they can study fine points of louse ecology.

And who among us would not be touched by that beautiful Dutch painting, “A Mother’s Duty,” of a kneeling child, head in mommy’s lap, getting deloused?

Any parent whose kid has had head lice, that’s who.

Every year, an estimated 6 million American kids will get infested with these wingless, six-legged crawlers, kids more often than grown-ups, girls more often than boys, Caucasians more often than African Americans. Louse infestations are probably the No. 1 reason for school absences, says Karen Maiorca, director of district nursing services for the Los Angeles Unified School District. But the district doesn’t record the precise number of infestations. Lice, health-wise, are small fry.

“Nobody dies from head lice,” or even gets sick from them, says Suzanne Rue, LAUSD’s communicable disease resource nurse. Not that Rue considers them any kind of picnic--”Oh, please” were the first words she uttered when the “L” word came up. But she and her colleagues save their case-tracking efforts for serious stuff like meningitis, scarlet fever and tuberculosis.

Head lice are simply a gross but harmless occupational hazard of being a kid--of clumping together in giggling, hair-braiding gaggles, of romping in a heap in the schoolyard, of pressing close to whisper secrets or snuggling, three heads to a pillow, at a sleepover. The cunning louse spreads and thrives via some of the loveliest cameos of childhood.

Which doesn’t make parents hate them any less. Lice, after all, too often mean that dreaded call from school with instructions to drop all, pick up Johnny or Janie, and spend hours applying insecticide, washing brushes and bedding, and dragging a comb through snarly locks.

And, for a creature that does no harm, the lowly louse incites a heck of a lot of passion, disagreement and confusion.

A Research Field Lousy With Controversy

In February, a San Francisco law firm filed a lawsuit in state court in San Francisco County against four companies that make head lice shampoos, claiming their products don’t work when used as instructed. Spokesmen for Pfizer, the maker of Rid, and Warner-Lambert, which makes Nix, said they don’t comment on pending litigation.

And last year, a Newton, Mass., consumer group, the National Pediculosis Assn. (pediculosis is the medical term for having lice) enraged Harvard scientists by leaking results of a louse study before they were published. The study supposedly showed that louse populations from several U.S. cities are developing resistance to permethrin, the active ingredient of Nix, a leading head lice treatment. (Other reports suggest American lice are fighting back against chemicals found in other head lice remedies.)

Some scientists who study lice see a conflict of interest in the NPA’s advocacy for combing as the sole treatment for eradicating lice, noting that the group also markets a $14.95 comb called the LiceMeister.

Meanwhile, debate rages about the best way to handle infestations. Some experts feel it’s unnecessary and unfair to pull kids out of class instead of sending them home with a note at day’s end. That it’s Draconian to insist every last louse egg (or nit) be removed before kids can return to school (the so-called no nit policy). Nits--when they’re hatched, or just dead--aren’t contagious, they argue.

“There’s no logical, rational basis for those policies,” says Richard Pollack, an entomologist at the Harvard School of Public Health. “It’s very hard to remove all the eggs. Yanking hair for hours--it’s nothing I would want to do with my child.”

Others--many school nurses, and the NPA--are strong supporters of the no-nit policy, which is enforced in many districts, including 700,000-student L.A. Unified district. Nurses can’t check every nit, they say.

“It’s a time issue,” says Rue. “It doesn’t make any sense to have anything other than a no-nit policy.”

If all this makes you want to tear your hair out, relax. Here, at last, is agreement: You don’t need to do that (or shave your child’s head) to get rid of lice.

Nor is it recommended that you rub hair with mayonnaise or olive oil to smother the brutes. (Neither of these home remedies work, experts say.) Another remedy, petroleum jelly, may indeed asphyxiate unwelcome visitors but is hard to get out of hair, traps lint and leaves, and makes nits harder to see.

And under no circumstances should you douse hair with flea or tick sprays. Gasoline or kerosene are no-no’s too, since they can cause nasty burns when children wander too close to flames.

What works? And to what level of Blitzkrieg must you subject your home? You won’t find 100% agreement among louse experts--in part because there’s still a lot unknown about just how lice spread.

Head Lice Are Homebodies

We should thank our lucky stars that of the 4,000 known louse species, people only get infested by three kinds. (You won’t catch lice from your pet, or give them yours.) There are pubic lice (or crabs), the head louse and the body louse, which lives in the seams of people’s clothes.

Body lice are responsible for a lot of the bad press head lice get. They flourish wherever people are clustered together under unsanitary conditions--by wars, natural disasters and poverty--and can spread dread diseases like typhus. There’s no evidence the head lice can do this.

Instead, the head louse passes its innocent, 30-day life biting its host every few hours, the females laying five to 10 shiny eggs a day, fastening them securely to the hair.

When it’s time to hatch, the baby louse sucks in air, then expels it, and pops out from the nit sheath. Voila: a cute baby louse.

Lice are most easily spread, experts agree, via head-to-head contact. Terri Meinking, assistant professor at the University of Miami School of Medicine, has artfully captured such spread in action.

While working in a small village in Panama where lice are more commonly accepted than in this country, she took 20 lice each from four girl volunteers, then painted each girl’s lice with a different dye: pink, green, yellow and turquoise. She returned each painted louse to the child whence it came, and sneaked in with a flashlight as the sisters slept together in a hammock. She saw that the dots of colors were now mixed evenly among the four heads. The lice were roaming freely in their newly expanded territory.

Head-to-head contact is one thing. But can you catch lice from farther afield--from stray hairs, the floor, bedding and combs? Ian Burgess, louse researcher at the Medical Entomology Center, a private consulting group in Cambridge, England, isn’t convinced.

Lice, he says, are homebodies unless another head comes close. And no wonder. Unlike the larger, sturdier body louse, a head louse will dry out and die if it doesn’t get frequent meals of blood.

Thus, while scientists have maintained colonies of body lice in labs for decades, no lab has ever spawned a head louse colony.

“I’ve tried keeping them in humidified chambers in the lab, giving them regular meals on the back of my hand,” sighs Burgess. “They can’t survive on four meals a day.”

Burgess says it’s unlikely you’ll catch a louse from a brush, batting helmet, bed linen or favorite teddy bear. Yet washing bedding, bagging toys, soaking combs and scrunchies, or spraying the house with louse sprays, are all recommended in the louse-busting literature. Burgess thinks this is overkill.

Meinking takes a more conservative position. Best to vacuum, wash bedding and soak those hair accouterments in louse shampoo or rubbing alcohol overnight, on the slim chance a hair with a live nit is lurking. She doesn’t recommend insecticidal sprays.

Here are some more of her tips.

Unlike the NPA, she doesn’t believe in fighting infestations just by combing. She’s had experience combing hair with living lice in it.

“I was sitting there watching the lice crawl toward me,” she recalls. “I looked down, and there were lice walking on my pants. On the floor. Fifteen feet away, climbing onto the arm of somebody who just happened to be sitting there.” Everyone, she said, got lice.

She does, however, agree with the NPA that one particular louse-killing chemical--lindane--should be avoided. Lice these days are pretty resistant to it. And it builds up in tissues and has been linked with some seizures in children.

And she doesn’t believe in routinely using any anti-louse shampoo for prevention. That’s where resistant head lice come from.

If you’re using prescription or over-the-counter shampoo, she says, don’t skimp on it. And rub it in to dry hair (so the insecticide doesn’t get diluted). Treat again in a week to catch lice you missed and new babies. No head louse shampoo will kill all the eggs.

If the lice come back, then switch to another product. Your lice may be resistant to the first brand.

For combing, use a good, fine-toothed comb. Applying hair conditioner will help the comb slide better. Nit-loosening products may or may not be effective.

Today, companies are working on developing new lice treatments. Scientists are studying the genetic structure of the louse to better understand how lice spread through communities.

In the meantime, we’ll just have to cope with this lousy situation. Remember: A head louse never killed anyone. Some cultures like their lice--or don’t, at least, get totally wigged out by them.

And, as any primate anthropologist will tell you, mutual grooming helps strengthen social harmony within family and tribe.

You’re not buying it, are you?

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Checking for Lice

Pay close attention to the nape of the neck and behind the ears. Lice are small, tan to grayish-white, with no wings.

Also look for:

* Tickly, itchy scalp

* Presence of louse eggs (nits). Look for tiny, shiny blobs attached neat the root of the hair. Unlike dandruff, nits won’t flake off.

* Check everyone in your household. Lice like your head just as much as they like your child’s.