Pharmacists Provide Crucial Link in Heading off Lice
Williams, Craig, Drug Topics
With fall soon upon us, many parents may find their children itching to get out of the house and return to school. Unfortunately, for millions of those children, school will be the source of an entirely new and more serious itch.
While easily preventable, lice infestation (pediculosis) is an insidious problem, estimated to affect more children nationwide than all other communicable childhood diseases combined. Fortunately, pharmacists are in an excellent position to help in eradicating these pests.
"We want to be sure that pharmacists understand that they can stop the spread of head lice," said Fred Mayer, president of Pharmacists Planning Service Inc. "Pediculosis is one health problem we pharmacists can do something about."
A nit-picking problem: At the forefront of the effort is the National Pediculosis Association, based in Newton, Mass. Celebrating its 10th anniversary, NPA is preparing to launch its ninth annual National Pediculosis Prevention Month this September. This year's slogan--"Picky, Picky, Picky"--is designed to call attention to the fact that it's time to get picky about children's health care.
"We need to deliver consistent messages about responsible health behavior to children," said NPA president Deborah Altschuler. This is particularly important today, as children grow up in a world of ever-increasing health risks, such as drug abuse and AIDS, she noted.
In fact, however, head lice are not taken very seriously, as Altschuler is quick to point out. "Although the Centers for Disease Control communicates regularly with the NPA, they delegate little else to the head lice issue," she complained. We are not trying to make lice more important than they are. But to disregard the endemic state of lice is a contradiction and a lost opportunity."
Lice may be pushing their own way into the spotlight, however. According to David Taplin, professor of dermatology at the Miami University School of Medicine, secondary bacterial infections following louse bites may be more common than previously believed.
Additionally, while it is still unclear whether head lice are able to transmit serious diseases like the closely related body louse, that may simply be the result of a lack of research, said Taplin.
In fact, new research on head lice has proved eye-opening. According to Taplin, the female louse lays five or six eggs a day, which take about 10 days to develop. The shell is impenetrable, except for a series of "airholes" used by the developing nymph. Current thinking is that pediculicides reach the nymph through this series of holes.
Seconds after emerging, the new louse begins to feed. The feeding process apparatus consists of three tubes; two are responsible for injecting anticoagulant, anesthetic, and vasodilator, while the third withdraws blood, said Taplin. But potentially more important is a relationship researchers have discovered between the developing nymph and some apparently symbiotic bacteria.
At the time the eggs are laid, the female injects several bacteria into each. Without them, the eggs are nonviable. A possibility, then, according to Taplin, is to one day be able to treat pediculosis with oral antibiotics. Oral treatment could offer a simpler, perhaps more acceptable means of treatment that could improve public compliance in the war on lice.
The primary tool used now is pyrethrin, a chrysanthemum extract that has been used as an insecticide for the better part of the century. Of the top-selling OTC brands, Nix, manufactured by Burroughs Wellcome, still uses permethrin, a synthetic derivative of the natural pyrethrin that the other major brands use.
Permethrin leaves a residue that lasts about two weeks; evidence points to its possible role in preventing reinfestation. But it must be remembered that these products, or their residues, are not inert. In fact, they are pesticides and need to be treated as such, especially in small children. …