Hair length and personal cleanliness are not factors in infestation rates. Lice infestation more often causes social embarrassment and isolation of the patient, rather than medical complications. All races are affected. Reported incidence in African Americans in the US is relatively less than in whites. Prevalence is higher in females than in males.
Pubic lice are more common in adults.
Patients may come to the ED after discovering lice or nits, which indicate infestation. Sometimes children are brought to the ED for evaluation when concerned parents learn about a case of lice at their child's school or daycare center. However, such findings are nonspecific. Although head lice are found on any part of the scalp, they most commonly are found in the postauricular and occipital areas. Eggs depend upon body warmth to incubate.