It was the first day of school, and Mallory, a Twin Cities teacher, had a problem.

A lice problem.

Because of it, she couldn't go to work.

Desperate to get rid of the itchy bugs and return to her job, she sought the help of professional nit-pickers whose novel approach to killing lice — using heated air instead of chemicals — caught her eye.

"It wasn't until I got lice that I was looking at their website and saw that they had this new product," said the Plymouth woman, who did not want her last name published.

There, on the Ladibugs Treatment Center website, she saw a picture of a machine that resembled a vacuum cleaner with a claw-like comb attached to it. Called the AirAllé (pronounced air-a-lay), it is becoming a popular weapon in the fight against lice.

Two dead lice on a specialty comb used for picking out the bugs.

The rise of "super lice," strains that have developed resistance to chemicals found in many over-the-counter and prescription products, has driven demand for new safe and effective ways to kill lice.

An estimated 6 million to 12 million U.S. children, ages 3 to 11, get head lice annually, according to the U.S. Centers for Disease Control and Prevention. The popularity of tablets and even smartphones can help spread lice, as children's heads touch while watching videos or playing games together. There's also the selfie effect — when kids' heads touch while posing for group selfies.

It takes just 30 seconds of head-to-head contact to spread lice from one person to another, according to Ladibugs. Sharing caps, clothes and other wearables from someone with head lice also can spread it.

And though lice can happen at any time, the back-to-school season is an especially busy time for professional nit-pickers.

Rachel Knutson and Lisa Rudquist started Ladibugs in Hopkins seven years ago. They have been using the FDA-cleared AirAllé since they opened. They say it kills head lice and 99 percent of their eggs through dehydration in just one session.

Although the device resembles a vacuum, it acts more like a blow dryer.

"It doesn't suck. It actually blows out heated air," Knutson explained.

The airflow is three times faster than that of a hair dryer and doesn't get as hot (the temperature is about 138 degrees), she said. This makes it safer than a blow dryer, which can burn the scalp, she added.

Following safety guidelines, the Ladibugs staff members do not use the device to treat children under age 4.

Avoiding chemicals

The Saturday morning of the Labor Day weekend, Mallory was lying in bed when she felt her scalp itch. She scratched. The itchies were concentrated near the nape of her neck. Based on her experience as a teacher who has checked students' heads for lice, she knew the nape of the neck was a common hot spot for lice, she said.

Immediately, she jumped out of bed and asked her husband to check her scalp. Sure enough, she had lice.

She tried an over-the-counter product, but it didn't get rid of all the bugs in her hair. Instead of using a stronger chemical solution, she opted for the hot air approach.

On the day of her appointment, Mallory sat quietly in the chair at the Ladibugs salon while manager Christina Doran, spoke to her in a soothing voice about what was about to happen.

"It will feel warm and relaxing," Doran assured her.

Then Doran placed the claw-shaped end on top of Mallory's head, moving across her whole head in a "switchback" pattern to ensure that she did not miss a spot. She wore a wrist timer that beeped every 30 seconds, prompting her to move the claw comb to another section of hair and blow hot air there.

After Doran finished heating Mallory's head, she applied a thick, oil-based serum to her hair and scalp — saturating the hair from roots to end to suffocate any remaining lice. Then she used a "nit comb" to rake through the hair and remove the debris.

Ladibugs charges $229 for the treatment and comb-out, which takes about an hour. For Mallory, it was worth it.

"The peace of mind is priceless," she said.

Allie Shah • 612-673-4488

@allieshah