By Dr. Mallika Marshall

BOSTON (CBS) – New clothes and a long list for the office supply store are all part of starting the school year. So too are concerns about head lice. The CDC estimates as many as 12 million children are infested every year and experts say it is getting harder to treat.

Kerri Verrette of Danvers found that out the hard way when she got a call from her daughter’s school last year. “Hi your child has head lice and you have to go and pick them up,” she said.

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The phone call wasn’t the worst part. Trying to treat her daughter at home proved to be a real challenge. “[There were] lots of tears. I don’t know if I cried more or if they cried more,” she said smiling at six-year-old Jordyn.

Lice (WBZ-TV)

Lice (WBZ-TV)

If misery loves company, Kerri has plenty of it. A study from the Journal of Medical Entomology found lice tested in 44 states, including Massachusetts, were resistant to over-the-counter chemical treatments.

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Eventually Kerri and Jordyn ended up at Lice Clinics of America in Danvers where technicians carefully combed the lice out of Jordyn’s long, blonde hair. They also used a warm air machine they say kills the bugs and eggs by dehydrating them.

Lice treatment at Lice Clinics of America (WBZ-TV)

Lice treatment at Lice Clinics of America (WBZ-TV)

Most home remedies require days or weeks of diligent combing to make sure every bug and nit is gone, but not here. And there’s a guarantee. “It’s one and done. We average about an hour per treatment,” explained technician Michelle D’Agostino, who has noticed a trend of older teenagers coming in for treatment. Believe it or not, she blames their phones. “Selfies is the big culprit with the older kids,” she said.

The phone is not an issue for Jordyn and she now knows to avoid sharing brushes or hats with other kids. “It’s really hard to go through lice,” she said.

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There are prescription treatments that are more effective against the parasites, but diligent coming for about a week is still recommended.

Dr. Mallika Marshall