Tests in 25 states have revealed an outbreak of drug-resistant “super lice” that are immune to current over-the-counter treatment options. Of course, this news comes as no surprise to scientists who have been reporting samples of head lice with very high levels of resistance to pyrethroids, the chemical found in most over-the-counter lice medications.

Although pyrethroids used to work 100 percent of the time back in 2000, research showed a drop in effectiveness to 25 percent by 2013. The Lice Clinics of America recommend using AirAllé, an FDA-approved medication that has shown promise in treating this drug-resistant strain. It costs $170 and is covered by most insurers.

“We use heated air and we dehydrate the lice and the eggs in a single treatment,” Claire Roberts, CEO of Lice Clinics of America, told KSDK. “It takes about an hour, and we guarantee it.”

From six to 12 million children between the ages of 3 and 12 contract head lice each year. Above all else, healthcare experts recommend prevention as the best treatment method for lice. That means avoiding hat and hairbrush sharing and actual contact with hair or another head. Clothing and bed sheets that have come into contact with lice should be washed and dried using hot water and hot air.

Dermatologists and pediatricians expressed concern for drug resistant strains of head lice back in 2013. A report presented at the American Chemical Society National Meeting and Exposition last August revealed that head lice throughout America are evolving to resist over-the-counter drugs containing pyrethroids.

Researchers have also tied an increase in head lice cases among teenagers to the rise of social media. Dr. Sharon Rink, a pediatrician from Wisconsin, said that selfies were to blame for a lice outbreak among teens.

“Teenagers don’t usually get lice because they’re not sharing hats and things like that,” Rink told ABC affiliate WBAY. “And lice can’t jump, so the only way they can transmit lice is touching their heads together, and that’s happening with all these photos. People are doing selfies like every day, as opposed to going to photo booths years and years ago. So you’re probably having much more contact with other people’s heads.”

While head lice are often associated with young children, anyone can contract them. Children are just more likely to have close physical contact with each other. Remember, lice cannot survive after going without blood for 24 hours. Contact your doctor before starting any hair lice treatment and avoid combining shampoo and conditioner with hair lice medication.