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Saturday, August 24, 2019

Don't you believe it; Head lice are not so super.

Head lice are not easily spread by hats, pillowcases, sofa backs or rugs.

Newspapers love a good story. The Globe and Mail, one of Canada's most respected newspapers, warned readers about the growing problem of super lice⁠—lice which have developed resistance to the insecticides in the traditional treatments. Hardy, resilient, tough to wipe out: No, I am not talking about head lice but about the stories, mostly myths, surrounding the pesky, little bugs.

When the Toronto District School Board announced it was reviewing its "no nits" policy, a media fire storm erupted. The "no nits" rule, once common in schools around the world, prevents those students with visible head lice eggs, nits, from attending school. The affected children cannot return until their heads are declared nit free. The rule sounds reasonable but isn't.

Teachers, parents and even health care workers often misdiagnose head lice infestations. When the Harvard School of Public Health examined samples of head lice and nits, more than 40 percent of the samples had nothing to do with head lice. This is why a "no nits" policy results in students being barred from school for such things as hat lint or dandruff. Of the remaining samples, approximately half or 30 percent indicated non-active infestations. Do the math. 70 percent of the samples were innocuous.

The Toronto Star fanned the fires of fear by conducting a highly suspect, online poll. The loaded questions determined most readers believed "nits are damaging to the kids." This came as no surprise since the story was replete with myths. Readers were warned, "Lice are a common problem among young children because they can be easily spread by sharing items like hats, brushes or combs." No they can't. Completely untrue. A myth.

Research has shown, and this is a quote, "the odds of head lice transmission via hats of lice-infested children is sufficiently low to be considered improbable and inconsequential."

With the school board in Toronto reconsidering its approach to the head lice problem, my local paper, The London Free Press, decided to do a take on the story but with a local twist. The fact that neither the public nor the separate school board was contemplating changes to the head lice policy should have made this a non-story but it didn't stop the paper. A grabber headline, a big picture of a concerned mother intent on protecting her young daughter from head lice, a separate fact-box with the usual stern warnings and voilĂ : a head lice story.

The Thames Valley District School Board cannot be faulted for being cautious. Without community support a move to discard the "no nits" policy may fail. Progressive boards which moved too fast have been forced to reinstate the discredited "no nits" policy after facing a flood of complaints from angry parents and, in some cases, teachers.

I contacted a school board in the States that had to backpedal on its decision to drop its "no nits" policy. The person I talked to felt the local newspaper was of no help in getting out the true head lice story. The newspaper preferred yesterday's myths to today's news.

Head lice are not a health hazard, they do not spread disease, on this everyone is in agreement. What they do is carry is a nasty stigma. They spread fear, stress and anxiety. Possibly, The Free Press should have run a picture of a young mother who no longer wants her children exposed to the possibility of being barred from school for having hat lint. Don't laugh. Remember the study done by the Harvard School of Public Health.

The little critters, only as big as sesame seeds, are unable to hop, let alone leap tall buildings, yet in the press they are called "super lice." There is nothing super about them. After years of being controlled with insecticides, the little bugs have done what insects do best—adapt. Head lice have developed resistance to the insecticides in the hair treatments used to fight them. This adaptation took no one by surprise.

But this very adaptability may well be their undoing. After living thousands of years as our uninvited guests, head lice are perfectly adapted to life on a human head. Off the human head, they don't fare so well. They die. (Reportedly, 55 hours off the human head and they're dead. That said, 72 hours without a blood feeding and they are done is a more often quoted time frame.)

With newspaper stories goading them on, fearful parents toss out pillowcases complete with pillows. Hats, scarves, coats are washed or even dry cleaned at some expense. Toys are bagged and left bundled for weeks. Almost everything a child with head lice has touched is considered contaminated by these frightened folk.

Rather than focusing on the environment, parents should focus on the affected child's head. The fear-driven cleaning response is totally out of proportion to the risk and this is thanks in part to the myths spread by our newspapers.

When I contacted the local reporter who wrote the head lice story, she referred me to her source, something she found on the Web. I thought, "You can't believe everything you read on the Web." The reporter's nose was so far out of joint because I dared to question her story, she has not talked to me since. Clearly readers should not question journalists.

It's claimed that Edward R. Murrow said of his own profession, "Journalists don't have thin skins. They have no skins." Sadly, I have discovered this observation on the sensitivity of many reporters to criticism is all too accurate. In this age of the Internet, with the ability to check any and all questionable claims, journalists would be wise to listen to a little criticism.

Google enough sources and you will soon realize there is a battle being raged over head lice. I like to think one side studies lice in the lab while the other studies lice in their environment, in the community, in schools and on children's heads.

To get the whole story, the accurate story, I contacted the people behind the claims. My search led me to Richard Speare, professor emeritus, James Cook University, Australia. Speare is one of the major players in the unraveling of the myth-riddled head lice story. Speare graciously responded to my email and attached a number of documents detailing some of his work.

Speare and his cohorts accepted that hats were considered high-risk items but could find little hard data supporting the all-too-common claim. The research team examined over 1000 hats in four schools. They also examined the students. The team found no head lice in the hats but over 5500 head lice on the students' heads. One myth busted.

The Australians also investigated the possibility of contacting head lice from contaminated floors. 2,230 children were examined from 118 classrooms. A total of 14,033 lice were collected from the children but not one louse was recovered from a floor. Researcher Deon Canyon doesn't mince words. He calls the risk of contacting head lice from a floor "zero." It is, he says, another groundless myth.

The out-of-proportion fear and stigma attached to head lice can make the lives of our most sociable little children quite miserable. Why the most sociable? Because they are the kids most likely to be making the head to head contacts that are almost always the source of the problem.

The reward for their social nature can be exclusion from school, isolation from friends, over-treatment and under support. Toddlers can find themselves ostracized by their best friends. It can be emotionally traumatizing. It doesn't have to be this way. The next time I see a story in the newspaper on head lice, I want to see a picture of a mother protecting her child from unwarranted emotional trauma. This would be a great story and this would be news.

The Centers for Disease Control and Prevention (CDC) in the United States has listed solid reasons for discontinuing "no nits" policies:
  • Nits more than ¼ inch from the scalp are usually not viable and thus are unlikely to hatch.
  • If nits are easily visible, they are most likely empty shells or nit casings.
  • Nits are cemented to hair shafts and are unlikely to be transferred to other people.
  • Misdiagnosis of nits is very common, resulting in children being banned from school in error.
  • Misdiagnosis can result in a child undergoing unnecessary chemical treatment.

Female head lice glue their eggs to the base of human hair shafts close to the scalp. And it must be a hair on a human head. A human body hair won't do. Nor will the hair of a favourite pet.

Also, the distance the egg is from the scalp is important. The eggs, called nits, are incubated by the warmth of the scalp. A growing hair can carry a nit too far from the warmth. It will fail to hatch. No oh-so-close warm scalp, no hatching. It's that simple. Adaptation is a weakness as well as a strength.

Now you can understand why the presence of nits does not indicate an active infestation. If the nits are easily seen, they are most likely not viable. Or the nits may be nothing but empty egg casing or bits of dandruff and the like, all misidentified by the untrained eye. The CDC knows all this but not all school boards and not many parents and certainly not many reporters.

It is claimed head lice have become difficult to eradicate. But it is not just head lice that have developed resistance to the insecticides used. Many parents have also developed strong resistance to the neurotoxins used in the treatments. More and more parents are hesitating to douse their child's head with powerful, poisonous chemicals to kill a benign pest.

Image courtesy: Community Hygiene Concern, Joanna Ibarra
The approach du jour is bug busting. A lubricant, often conditioner, is used with water to wet the hair. The lubricant makes it difficult for the lice to move quickly and thus avoid the fine-toothed nit comb sliding through the hair from the roots to the tips.

Bug busting is nit picky. The goal is to physically remove all nits and lice from the infested head. Many people have neither the time nor the patience to see the process through. The failure rate is quite high.

Others believe an oil, such as coconut oil, will coat the bugs and suffocate them. It will certainly slow them down but lice are resilient. This approach has yet to find clear support from scientific testing but those wanting to asphyxiate the little critters may be on to something.

One product available in Canada, Nyda, combats head lice by using the asphyxiation method but kicks it up a notch. During an interview on Radio New Zealand, Professor Rick Spears was asked, "How essential is a nit comb for getting rid of head lice and nits?" The professor answered:

With some of the new dimethicone based products, some of the silicone based oils penetrate the egg too, so the embryos die as well. In that case you don't have to comb them all.

That's Nyda! Nyda is a dimethicone based product. And it claims not only to kill lice but also nits. In many cases one treatment is often sufficient, the maker says. If necessary a second treatment ten days later guarantees a lice-free head. No neurotoxins are involved. Nyda is safe but keep it out of the eyes. You don't want a child fighting head lice to also be fighting the caregiver, you, and the treatment.

I chatted with a family that used Nyda as directed. The parents told me that Nyda appeared to eradicate the head lice after just one treatment. But the affected child was treated again after ten days just to be sure. The family asked me not to go into too many details as they had discovered the London school their child attends does not follow the "no nits" policy but mum's the word. It is a school policy and not a board directive. The principal and teaching staff are clearly enlightened.

The parents read The Free Press article and realized the paper wasn't enlightened. The paper and the reporter were still living in the head lice dark ages. Mythology still rules.

If it makes you feel better, wash that toque, put those sheets in the dryer and set it to hot, bag those toys, vacuum the floor and carefully dispose of the dust bag. But do try to relax, shake off your fears. Take comfort in the facts and forget the myths.

Remember: head lice are adaptable and they've adapted to heads. Off the human head they are dead within as little as six hours. You see, the damn little things aren't so super after all.
Other links:

Follow link and do a search of the pages for chapter titled Lousy Science.

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