The head louse is a tiny insect that infests the hair and can cause chronic itching, especially along the hairline on the back of the neck. Scratching may cause irritation, and secondary infection can develop. The presence of head lice does not necessarily reflect poor hygiene. In fact, frequent bathing will not remove the lice but can aggravate the itching of the scalp.
Head lice are highly contagious and are spread from one child to another through direct contact.
The condition can frequently spread from one sibling to another and among children at school or day care. Infested hats, scarves, combs and brushes may also spread the insects to other children. The lice multiply by laying eggs called nits, which appear as tiny dandruff flakes. Parents can identify the nits by closely examining the child's scalp. The nits are attached to the hair shaft and, unlike dandruff, cannot be easily removed.