By Deborah Z. Altschuler
“They use combing to validate an active infestation, quantify lice and nits by counting what the comb removes from their test subjects, as well as confirm and compare therapeutic efficacy.”
The March 11, 2010 New England Journal of Medicine published a study comparing the use of a pesticide called malathion to the use of an oral antibiotic called ivermectin to determine the efficacy of each in treating children with head lice (pediculosis). http://content.nejm.org/cgi/content/short/362/10/896
According to this report, head lice are universal human parasites affecting over 100 million people worldwide each year. The study was conducted on children who had already been treated with topical insecticides yet continued to have live lice. “Infestation was confirmed and monitored by means of fine-toothed combing.” Adverse events for the participants included gastroenteritis, nausea, vomiting, impetigo and convulsions.
The ivermectin (antibiotic) comparison study was performed on children as young as 2 years of age. Earlier studies using malathion have been performed on children as young as 6 months of age. A list of various other new products for killing lice are being studied with future ivermectin trials scheduled for very young children.
Study after study reminds us that none of the experimental treatments, or those already cleared by the FDA, are 100% effective against lice and nits (lice eggs). This is why the product label for pediculicides (pesticides) recommends retreatment in 7-10 days. It also reminds us that children are exposed to 2 applications of pediculicides with the purchase of one treatment. Therefore it is curious that the NEJM article offers “that in real life, the persistence of live lice one day after insecticide application strongly suggests resistance.” There are many variables to account for treatment failure. Resistance is just one of them. Remaining nits that hatch new lice is another.
And while we have documented evidence of lice resistance to some of the most widely used products, it is unimaginable that physicians would choose to use a heavy hand with antibiotics when safer choices are available.
Rather than take the inherent health risks of following one insecticide or chemical or prescription with another, a more rational approach would be the same method researchers rely on to account for their scientific findings. They use combing for lice and nits to validate an active infestation, quantify lice and nits by counting what the comb removes from their test subjects, as well as confirm and compare therapeutic efficacy. In fact, the development of effective combs has been a boon to clinical studies – allowing for more objective data collection. The combing method is accepted and published as an integral part of clinical trials.
Perhaps with a dose of irony, the NEJM article is another example in which combing is required for research and product development. This includes a study NPA found not only promising as an important compliment to combing, but also as a much more rational non-chemical alternative to pesticides.
As published in 2006 Pediatrics: “After using a louse comb to confirm infestation, one side of each participant’s scalp was combed thoroughly to remove all lice and eggs as a control. The child’s whole head was then treated, followed by a thorough combing of the non-control side of the head.” (Italics added for emphasis). http://pediatrics.aappublications.org/cgi/content/full/118/5/1962
Perhaps the greatest benefit to recent clinical studies is the way in which they offhandedly and consistently stress that “all lice and eggs” can be removed and accounted for with combing.
And it’s not just about live lice as the NEJM article seems to imply. Nits must also be accounted for. Infestations are established by lice laying eggs that hatch new lice. This is their cycle of life -– their basic biology.
Combing is a scientifically reliable method to remove all lice and nits – which is another way to say it can end an infestation – literally. Combing is the safest and most cost effective approach that accomplishes what chemicals cannot. It enables families to be self-reliant, proactive, and preventive. It allows for regular screening and early detection which makes the combing approach even more practical and realistic.
While chemical treatments, pediculicides, and broad spectrum antibiotics develop resistance and potentially adverse health effects, nothing compares to the kindness of a comb.
Deborah Z. Altschuler
National Pediculosis Association