Lice are tiny, gray insects that can affect a person's hair or skin. Head lice attach themselves to the hair shafts. Body lice live in the seams of clothing and come out to bite the person's skin.

What is going on in the body?

Head lice cause itching and scratch marks on the scalp. Body lice actually live in the seams of clothing, not on the skin. The lice will leave the clothing to bite the infected person. The lice leave eggs, also called nits, attached to the hair shafts.

What are the causes and risks of the disease?

Head lice spread by head-to-head contact, such as sharing hats and combs or sleeping next to another person. It is most common in school-age children. Becoming infected with head lice has nothing to do with poor hygiene.

Body lice are common among people who are unable to wash their clothing regularly. This condition is sometimes called "vagabond's disease" and is typically seen in the homeless.