Whether you kill them with hot or cold air, attack them with chemicals or natural remedies, or meticulously comb them out live, lice infesting a child’s head are a problem that demands to be addressed.

Though they generally don’t pose health risks, lice infestations can close schools and often create a major impact at home that can feel like a serious medical event to parents. Infestation carries an unfounded, but undeniable, social stigma. Half the time, mothers pick up lice from their kids by the time the family infestation has been discovered.

But the array of treatment options can be perplexing. Drugs and equipment to treat lice are a $1.9 billion market growing at a 6.5% pace, according to analysis by Market Research Future. And the market has been fundamentally changed by the rise of lice that are resistant to the common over-the-counter treatments, lice-removal professionals said.

“My first thing for parents is: Don’t panic,” said Dana Mead-Campion, co-owner of the Simply Nitty lice-removal salon in Edina, Minn. “I try to explain, ‘This is not an emergency. You’re OK.’ The coaching that we do is probably 90% of our jobs.”

This year, the Ladibugs clinic in Hopkins quietly launched a new medical-device treatment that uses cold air to kill the bugs. Called Zyma Air Therapy, it should be available to other lice clinics nationwide by year’s end. Based on a cold-air blower manufactured by the device company Zimmer, the therapy is being patented and registered with the U.S. Food and Drug Administration.

Many other anti-lice solutions are promoted to parents, from prescription and over-the-counter lotions and shampoos, homeopathic sprays and home remedies. Other medical devices are registered or cleared with the FDA, like specialized “nitpicking” combs, as well as the proprietary hot-air blower used at hundreds of Lice Clinics of America locations, including one in St. Cloud where teachers and nurses can get free lice-removal treatments.

While finding lice sends parents into a frantic search for information, it doesn’t help that much of the information on the topic found online is either old or incomplete.

The Centers for Disease Control and Infection promotes the use of over-the-counter “pyrethroid” drugs, even though most lice in the U.S. have a genetic resistance to them. The Food and Drug Administration promotes only drug treatments, though it has cleared or registered several medical devices, including lice combs. The Minnesota Health Department website still promotes “alternative” treatments like slathering the head in mayonnaise or olive oil.

No government agency publishes official statistics on head lice incidence, but many publications quote from a speculative estimate published by the CDC in 2013 of 6 million to 12 million infestations annually in the United States among children 3 to 11 years of age. Some studies suggest girls get head lice more often than boys, “probably due to more frequent head-to-head contact,” according to the CDC publication.

Go to a pro?

Guidance published in 2015 by the Illinois-based American Academy of Pediatrics said that while head lice are not a health hazard, more physician involvement with lice cases is recommended, because of the potential for misdiagnosis and the recent emergence of newer drugs following the discovery of treatment-resistant lice.

“Optimal treatments should be safe, should rapidly rid the individual of live lice, viable eggs, and residual nits, and should be easy to use and affordable,” the guidance report says. “Because lice infestation is benign, treatments should not be associated with adverse effects and should be reserved for patients on whom living lice are found.”

Deborah Altschuler, president of the National Pediculosis Association in Massachusetts (“pediculosis” is the medical term for lice infestation), said it might not be bad idea to see a doctor for lice because sometimes children can get secondary infections from scratching or have allergy issues with medications.

“Some parents simply have no confidence in what to do and need the reassurance of their family physician,” Altschuler said. “That said, guidelines that ‘drive’ people to the physician are still a red flag that it’s industry-initiated — often wanting that person to get a script for one or more of the more expensive (and not necessarily more effective)treatments.”

Altschuler said parents can take care of the problem at home through diligent use of a special nitpicking comb called the LiceMeister, developed by the association and available online for about $12. “The comb is the most important tool in the management of head lice,” she said.

Stop them cold

A whole industry of small “nitpicking” clinics emerged in the past decade, all revolving around the use of such combs, along with various types of natural or nonpharmacologic goo that can either suffocate the bugs or chemically break down their exoskeletons.

Simply Nitty is one such clinic in the Twin Cities. Lice-removal pros there are certified in the Shepherd Method, which involves examining and combing 50 to 100 strands of hair at a time. Co-owner Mead-Campion said parents armed with a good comb can do this job at home, given enough time, patience and familiarity with lice, though she said, “We wouldn’t be in business as professionals, honestly, if lice were easy to get rid of.”

Rather than waiting for outbreaks, she encourages parents to do routine screenings with a clean comb at home to catch lice before they are contagious. She endorses the Terminator comb from Nit Free, for about $12.50.

Other parents might want the assurance of having the bugs killed before combing them out.

That’s where clinics offering treated air come in. The most well known is Lice Clinics of America, a fast-growing chain with 330 outlets in 36 countries. LCA uses an FDA-cleared technology called AirAllé, which applies air heated above 130 degree to dehydrate lice and nits, killing more than 99% of eggs in an hourlong treatment that may also include combing out the bugs afterward.

“Remember, it’s a slow build. It always starts out with one or two bugs. And they lay three to five eggs per day,” said Rainya Strack, a former school nurse who now runs the LCA clinic in St. Cloud, Minn. “Typically by the time families get to our clinic, it’s been four to six weeks.”

The newest alternative is Ladibugs’ Zyma Air Therapy, which blows air cooled to 20 degrees. The Ladibugs clinic in Hopkins is a former LCA location, but recently dropped that affiliation to offer Zyma therapy. The device is expected to be available to other authorized clinics before the end of the year.

Just going outside on a cold winter day won’t kill lice because the bugs live close to the scalp where it’s warm, but Zyma involves blowing cooled air at the hair roots just above the scalp for 30 minutes, followed by a comb-out.

Ladibugs co-founder Lisa Rudquist said the FDA-registered system has been used in more than 700 cases, with a 100% success rate, though the data are not yet published. And unlike chemical-based treatments, air therapy won’t breed stronger bugs, she said.

“When you kill lice with something natural like cold air … there’s no perpetuation of lice resistance. So we stop that process,” Rudquist said. “There is not going to be any lice that are resistant to cold air.”