Head Louse
The head louse makes itself at home on the human scalp, eyebrows, and eyelashes, which is where you’ll find this annoying parasite. An estimated six million or more children are infested each year in the United States alone.
While nestled close to the scalp, the louse feeds every few hours on a steady supply of human blood. Head lice do not spread diseases, but they can cause itching and other mild symptoms and often must be treated with medication.
Head lice go through three life stages. Over the course of its lifetime, females may lay 50 to 150 eggs—or nits—on hairs the scalp. The eggs can resemble dandruff. After about a week, the eggs hatch and release nymphs, which are roughly the size of a pinhead. After another week, the nymphs grow into adults that are about the size of sesame seeds.
Each louse has six legs and each leg contains its own claws! Ouch!
Head lice often spread from person to person by direct head-to-head contact, though they can be transmitted through clothing, brushes, beds, or other items that have been in contact with an infested person.
With a constant supply of nourishing blood, adult head lice can live on a person’s head for up to a month!