FRIDAY, Aug. 5 (HealthDay News) -- Combing wet hair with a
fine-tooth comb is a more effective treatment for head lice than
over-the-counter chemical products, a new British study finds.
The discovery is important because head lice are showing increasing
resistance to over-the-counter treatments, according to the
Head lice are tiny, wingless insects that feed on small amounts of
blood. And they are easily spread, particularly among children,
through close contact and sharing personal items such as hats.
Common chemical head lice remedies such as Nix and malathion appear
to be increasingly ineffective against head lice. Nix cured only 10
percent of head lice cases and malathion only 17 percent, the
"Our study confirms that developing insecticide resistance in head
lice to the main two actives used in pediculicides -- organophosphates
and pyrethroids -- makes them very ineffective," said lead researcher
Nigel Hill, the head science officer in the department of infectious
and tropical diseases at the London School of Hygiene and Tropical
"Whilst I feel many parents and health professionals already
believed this to be the case, our study has shown just how low success
rates with these products really are," he added.
The study results appear in the Aug. 4 online edition of the
British Medical Journal.
In their study, Hill and his team compared chemical treatments with
a product sold in Great Britain called the "Bug Buster kit." Each kit
includes special combs that remove lice and nits, and the instructions
call for using the combs along with hair conditioner while the hair is
wet. Hair washing and combing is supposed to be done four times over a
During the study, 126 children with head lice were assigned to
treatment with the Bug Buster kit or the insecticide treatments. The
researchers looked for head lice two to four days after the end of
Hill's team found that the Bug Buster kit was four times more
effective in curing a head lice infestation than the chemical
products. The cure rate for the kit was 57 percent, they reported.
"This is the first hard evidence that the methodical use of a
well-designed fine-tooth comb in wet and conditioned hair can break
the life cycle and effectively eradicate lice," Hill said. "So-called
wet combing with conditioner has been widely advocated for several
years as a treatment, but with no real evidence it worked. Our study
shows clearly it is a viable alternative to current medicated
The researchers realize that the Bug Buster results aren't totally
satisfactory. "Some may consider that the cure rate of only 57 percent
we detected with the Bug Buster kit is still unacceptable and may not
provide an efficient treatment against head lice," the authors wrote.
"We would like to see manufacturers of insecticidal compounds and
formulators of pediculicidal products urgently address the need for
novel actives to be registered for use against head lice," Hill said.
"There are already candidate compounds which are likely to be 100
percent effective, and every effort should be made to bring these to
market as soon as possible."
One expert believes the new study demonstrating the emergence of
chemical-resistant head lice could foreshadow problems in the United
"There is a scary lesson to the American public in this study,"
said Dr. Dale Lawrence Pearlman, of Family Dermatology in Menlo Park,
Calif., and inventor of a nontoxic head lice treatment, called Nuvo.
"The study concludes that in a country like England, which has
extensively used nerve poison-based stuff, you're going to produce a
population of head lice that are mean, ornery and not killable with
nerve poisons," he said.
Pearlman noted that in the United States, Nix is already considered
unreliable for treating head lice. Malathion, which has just been
released for use in the United States, may also breed resistant head
lice like those seen in the British study.
"Their result with Bug Busting suggests that you can cure about
half the kids," Pearlman said. "That's a disappointing number. In
addition, what happens two months later? It means that they can get
re-infested by the kids that Bug Buster didn't cure."
Pearlman believes the answer to head lice lies in the development
of nontoxic approaches that the lice cannot become resistant to.
"There is also the very scary scenario that parents can expect that
the more neurotoxic products are used in America, the more we are
going to have a problem of resistance like the British," Pearlman
The National Pediculosis Association can tell you more about