The problem with head lice is they are small, parasitic insects that feed on blood under the scalp. Because of this, they live in the hair near the scalp. Their eggs, known as nits, are secured near the root of hair by a natural, glue-like substance, which makes them hard to remove. The live lice are easily spread through head-to-head contact and can also be spread by sharing headgear such as hats with an infested person. Of the 12 million cases of lice infestation that are estimated to occur each year in the United States, many of these are children. Due to after-school sports, playing during recess and playing around with friends in general, kids are more likely to spread lice amongst themselves.