Adult head lice live about 1 month on their host and seldom longer than 2 days when removed. A female head louse may deposit 4 eggs per day totaling 50 to 150 eggs during its adult life span. Eggs hatch in approximately 7-10 days. This process causes intense itching. Scratching to alleviate the itch may lead to secondary infections that may form sores.
Pediculosis is the medical term used to describe the condition of being infested with lice.
Head lice can infest anyone due to their communicable mode of transmission. Spread is usually direct from person to person contact or indirectly through shared objects such as combs, hairbrushes, caps, scarves, coats, sheets and pillowcases. Head lice are poorly adapted for survival off the host. They do not flourish on desks, carpet, lockers, chairs, school bus seats or other objects. The first sign of a head louse infestation is constant scratching of the head.