Method to measure force required to remove Pediculus humanus capitis (Phthiraptera: Pediculidae) eggs from human hair.
Head lice are very common and mainly affect children between 3 and 12 yr old. Little is known about the way nits, the eggs of the head louse, are attached to the hair. In this report, an objective measurement procedure for the ease with which nits can be removed is presented. The first peak force, associated with the start of nit movement, and the average and maximal force during the sliding of the nit were measured. The three force variables correlated with the length of the cylinder by which the nit was attached to the hair. A negative correlation was found between the maximum force exerted and the distance of the nit from the scalp. The method described in this report can be used to determine the in vitro efficacy of various products to remove nits.
Lapeere
Hilde
H
Department of Dermatology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
Brochez
Lieve
L
Haeghen
Yves Vander
YV
Mabilde
Cyriel
C
Stichele
Robert Vander
RV
Leybaert
Luc
L
Naeyaert
Jean-Marie
JM
D000818:Animals; D001696:Biomechanical Phenomena; D002648:Child; D002675:Child, Preschool; D006197:Hair / Q000469:parasitology*; D006801:Humans; D010373:Lice Infestations / Q000469:parasitology; D010063:Ovum / Q000502:physiology*; D010374:Pediculus / Q000502:physiology*