Lice: The Real Nitpicking

I can’t remember how old I was when I figured out that the term nitpicking must have come from picking lice nits. And if it didn’t, well that’s what I always associate it with anyway.

We had lice in our family 11 years ago, just before Christmas. It had bypassed us for so many years, I guess we were lucky. My boys were in 2nd and 6th grade, and my daughter in 4th.  We hear so much about lice that I figured it must have fairly high infection rates. But, according to a press release issued by JAMA, although it one of the most common childhood infections, it affects between 1% percent and 3 % of 6- to 12-year-olds in industrialized nations.

One of the most tedious and frustrating part of getting rid of lice is checking the hair for tiny nits that could be easy to miss. In fact, in my experience, children who were sent back to school too early, meaning that they still had lice but it wasn’t yet apparent, had nits that their parents or caregivers missed.

A study published in the most recent issue of JAMA says that we may be going about looking for those nits the wrong way. Instead of looking for them in dry hair, we should be looking through wet hair. In the study, children were examined with their hair dry. The researchers used the standard technique of using an object, in this case an applicator stick, to part the hair and look for nits. After the children were examined, a second researcher, who didn’t know what the first one found or didn’t find, applied some conditioner to the children’s hair and then combed the length of hair with a fine-tooth comb. The comb was then wiped and if there were any objects on the comb that transferred to the paper, they were examined under a microscope.

What were the results?

“Visual inspection underestimated the true prevalence of active infestation by a factor of 3.5,” the authors write. Wet combing had a significantly higher sensitivity for detecting active infestations, correctly identifying them in 90.5 percent of the children (vs. 28.6 percent for visual inspections). However, visual inspection had a higher sensitivity for the identification of historic infestations (86.1 percent vs. 68.4 percent).

You can read more about the study and its findings in this press release: Wet combing more accurate than visual inspection for identifying active head lice infestation.

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Images: MorgueFile.com