Lice are very common, especially among schoolage children.
Transmission is via head to head contact and it has nothing to do with personal hygiene.
The head louse is a tiny greyish brown insect, about 2.5mm long. Head lice are usually found on the scalp and live on blood from the 'host' which they get by biting through the scalp. Adult lice mate and the female then lays eggs which are firmly attached to individual hairs close to the scalp and can be very difficult to remove. After seven or eight days the baby louse hatches out of the egg, leaving a shiny white empty egg shell or 'nit' which may be found anywhere along a strand of hair. Infection with head lice is a very common problem in the UK, especially amongst school age children.