Epidemiology of head lice infestation in school children at Peshawar, Pakistan.

An epidemiological survey of head lice infestation among school children at Peshawar (Pakistan) was conducted from April to December 1986. Lice were detected by visual inspection and combing of the head. A total sample of 2287 students (1499 girls, 788 boys) aged 8-16 years from six schools revealed an overall prevalence of 46%, with girls showing a higher infestation rate (49%) than the boys (40%). The infestation in girls was more common in one of the three girls' schools surveyed, while in boys it did not differ significantly among different schools. The prevalence decreased as a linear function of age in both sexes. Pediculosis was directly related to hair length, and the rate of decrease with age was uniform in the three hair length categories compared. The infestation was directly related to crowding at home, and was negatively associated with dandruff. Like prevalence, the degree of infestation was higher in girls than in boys and decreased linearly with age in both sexes.