Louse or Lice for plural form, are mostly scavengers. Generally, they latch onto a human host and feed on the skin found on the host's body. Normally lice do not live in colonies. However, once established on the human host they will reproduce in size and number and continue to live off of the host until completely removed. There are many different types of lice, with some species pertaining only animals or humans, and others being able to go to any other species.
You are at greatest risk of getting lice if you come into close contact with someone who already has lice. Direct contact is the most common way to get lice, however, you can also get it from contact with an infected animals or infected persons clothing (such as hat, coat, scarves, hair ribbon) or other personal items (such as a brush, comb). Avoid contact with those infected and be sure to get your house inspected if you notice your animal of family excessively itching.