Childhood: Combing Through Wet Hair May Be Best Way to Find Lice
NICHOLAS BAKALAR
Published: Tuesday, March 24, 2009 at 3:30 a.m.
Last Modified: Monday, March 23, 2009 at 5:11 a.m.
Figuring out whether a child has head lice may require more than just taking a look.
German scientists examined 304 children at five primary schools that reported persistent head lice infestations. First, a researcher examined their scalps, parting the hair at five places where eggs or lice are often found. Then a different investigator, unaware of the results of the first test, examined the same children, this time wetting the hair with conditioner and running a fine-tooth comb from the scalp to the end of the hair. The results appear in the March issue of The Archives of Dermatology.
Visual inspection found eggs or nits — that is, evidence of prior infestation — in 68 of the 300 children, while wet combing found such evidence in 54, so visual inspection was quite good at finding the eggs. But living lice are the moving transmitters of the epidemic, and visual inspection found only 6 cases, while wet combing found 19. In other words, the odds of finding moving lice were about three times higher with wet combing.
“Interrupting the epidemic means finding out who is infectious and who is not,” said Dr. Hermann Feldmeier, the senior author and a professor of microbiology at Charité University Medical School in Berlin. “For this purpose, the only suitable diagnostic technique is wet combing.”