Lice are small wingless insects that infest the head. They lay eggs that adhere closely to the hair shaft. The eggs stick on the head with an almost glue like substance so they are hardest to get rid of.
Head lice can spread through direct head to head contact. Children tend to pick it up at school especially because they are in close contact with one another.
The symptoms to watch out for are itching caused by reaction to the bites, sores and bumps on the head.