The head louse - commonly known as lice - is a parasitic insect that can most often be found on the scalp, eyebrows and eyelashes. To sustain themselves, lice feed on human blood. In most cases, lice are not known to spread diseases between humans. In the United States, around 12 million people suffer from lice each year, with most infections occurring in children. Lice spread by direct contact with an infected person.
In fact, hygiene and cleanliness have nothing to do with the spread of lice. Some of the symptoms of lice include a tickling feeling of something moving in the hair. Itching caused by an allergic reaction to bite of the lice is also a common symptom. Most people also report difficulties sleeping at night. This is due to the fact that lice are most active during the night. Lastly, lice bites may cause the appearance of sores on the scalp. Most treatments for lice infection include prescribed shampoos or special combs.