Head Lice - Small Parasitic Insects

Head lice (Pediculus capitis) are small parasitic insects exquisitely adapted to living mainly on the scalp and neck hairs of their human host. Their six impressive legs are elegantly evolved to grasp hair shafts and provide a striking example of biological specialization. Long associated with people, head lice have been recovered from prehistoric mummies. Head lice are equal opportunity parasites; they do not respect socio-economic class distinctions. Their presence does not connote a lack of hygiene or sanitation practiced by their host. Head lice are mainly acquired by direct head-to-head contact with an infested person's hair, but may infrequently be transferred with shared combs, hats and other hair accessories. They may also remain on bedding or upholstered furniture for a brief period. 
 

Do Head Lice cause harm?
Head lice rarely (if ever) cause direct harm, and they are not known to transmit infectious agents from person-to-person. Thus, they should not be considered as a medical or a public health problem. These lice may occasionally be burdensome because of annoyance; their presence may cause itching and loss of sleep. The louse's saliva and feces may sensitize people to their bites, thereby exacerbating the irritation and increasing the chance of secondary infection from excessive scratching.