Wet Combing More Effective for Detecting Head Lice than Traditional Visual Inspection


Published: September, 2005

Head lice are minute, parasitic insects that live in hair. They easily spread from person to person, especially among children at school or in day care, and they are responsible for many school absences. Because lice are barely visible, finding lice eggs, called nits, is the easier way to detect an infestation. These tiny, white flecks cling to hair shafts. Researchers at Belgium’s Ghent University recently found that carefully sweeping a fine-toothed comb through wet, conditioned hair is more effective for detecting lice than the traditional, dry-scalp visual inspection.

The study, published in the British Medical Journal, compared the two methods on 224 school children. Two trained teams independently examined the students: one using the wet comb technique, the other using the visual test. Wet combing found lice in 49 children, while the visual test only detected 32 of these cases. In addition, the traditional inspection mistakenly identified 14 uninfected children as having lice.

The results suggest that compared to traditional, visual inspection, wet combing would allow for more accurate head lice detection, meaning more infestations detected before they can spread, and fewer non-infested children receiving unnecessary treatment with insecticides.

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