More nits to pick: Head lice resist treatment

In the arms race against lice, the insects have a leg or six up.

Researchers say lice have mutated to develop a resistance to many over-the-counter remedies that parents and health officials have traditionally used to combat the tiny pests. Resistant lice are dominant in 42 of 48 states researchers studied.

In a study published in the Journal of Entomology and presented at the American Chemical Society National Meeting, researchers found the superbugs are resistant to pyrethroids and pyrethrins, which are the key ingredients in many over-the-counter treatments. The resistant mutations “are widely and uniformly present in U.S. lice,” the researchers wrote.

“It’s kind of alarming,” lead researcher Kyong Sup Yoon of Southern Illinois University told Yahoo Health. “A ton of products are not working.”

Back to school, with its lice hazards

Head lice tend to pose problems when kids return to school and start sharing personal items and cubbies or lockers.

Lice are tiny and nimble insects, which make them hard to see. Your child may tell you about itchiness or a tickling sensation along the hairline or on the scalp. You may notice redness, red bumps and dandruff flakes that aren’t easily brushed away. Examine your child’s head for lice under a bright light with a magnifying glass or strong reading glasses.

Lice are annoying pests, but they aren’t dangerous, experts say.

“The good news is head lice don’t carry disease,” Yoon said earlier this year. “They’re more a nuisance than anything else.”

Learning about lice

The study was published in the Journal of Medical Entomology.

The news web site Boston.com reported that Yoon’s research was partly funded by companies selling alternatives to traditional over-the-counter treatments for lice. The alternatives are mostly available only by prescription, reported the site. But the study was peer-reviewed before publication.

Providence Health Plan has information about how parents can detect the presence of head lice, treat the scalp when they are found and avoid spreading them. See “Heading off head lice.”

The U.S. Centers for Disease Control and Prevention responds to Frequently Asked Questions on its website. Sample question: If the treatment for head lice doesn't seem to be working, does this mean the lice are resistant and I need a different treatment? The answer: Not necessarily.

If lice have already infested your family, talk with your health care provider about the best way to eradicate them. You can find a Providence provider in our directory.