ATLANTA (CBS Atlanta) – New worries for parents treating children with head lice.
A new study finds the critters have developed a genetic resistance to over-the-counter treatments.
Researchers from Southern Illinois University collected lice from 30 states.
“We are the first group to collect lice samples from a large number of populations across the U.S.,” explained lead author Kyong Yoon. “What we found was that 104 out of the 109 lice populations we tested had high levels of gene mutations, which have been linked to resistance to pyrethroids.”
Pyrethroids are a class of insecticides that includes permethrin, the active ingredient in some of the most popular lice treatments.
The researchers found lice with genetic mutations that increase their resistance to pyrethroids in 25 states, including California, Texas, Florida and Georgia.
Intermediate levels of pyrethroid-resistance were found in four states: New York, New Jersey, New Mexico and Oregon.
Of the 30 states the researchers looked at, only Michigan had lice that was still vulnerable to treatment with pyrethroids.
The National Pediculosis Association warns that if a lice treatment doesn’t work, parents should stop using it, and should not use any other product to avoid exposing the child to too many pesticides.
It warns parents should not use Lindane (a prescription treatment that can cause serious side effects), kerosene or pet shampoos.
The Association advises manually removing the nits, or lice eggs, with a nit-removal comb.
The Centers for Disease Control and Prevention as many as 12 million American school children between the ages of 3 and 11 get them each year.
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