" Lice are a type of parasitic insect that feed on blood and use animals or people as their host. Lice live in the hair of their host. This can include the hair on your scalp, eyebrows, eyelashes, and pubic hair. Lice multiply quickly and spread easily from one person to another. That means that when one member of the family has lice, the entire family is at risk. Here’s what you can do to ...