Headlice

Head lice are tiny insects that live on the scalp. Many families with young children have at least one encounter with the head louse, Pediculus humanus capitis . As the name implies, head lice are specialized to live among the hair present on the human head and are exquisitely adapted to living mainly on the scalp and neck hairs of their human host. Head lice develop in three forms nits, nymphs, and adults. Head lice can infest people of all ages, but children are prone to infestations because of their habit of playing in close contact, sharing hats, headphones, combs and brushes, sleeping bags, stuffed animals, and clothing. In fact, the problem of head lice can be so rampant among preschool and school-aged children that often schools must work in conjunction with many families to control an infestation. An individual family may be able to control head lice at home, but the child can be reinfested when he/she comes in contact with an untreated, infested child. The eggs hatch after 7 to 10 days, and 10 to 14 days after hatching the lice are mature and between 2 and 4 mm long (the size of a sesame seed). Once mature they start to reproduce, so numbers can grow alarmingly if not treated.

Head Lice are tiny brown and gray parasites that can cause itching and scratching, especially on areas of the body that are covered with hair, ie. typically the scalp, neck, and behind the ears. A head louse is an insect that lives on the human scalp and feeds on blood. Lice lay eggs (nits) on the hair close to the scalp. It takes about 6 days for the nits to hatch. Nits have to be on the hair near the scalp in order to hatch. Nits which have been dislodged will not hatch in the environment. Nits are easier to see than lice. Head lice have a head, thorax and abdomen with six legs , but their two front legs are very large in order to grab onto the hair shafts. Head lice are tan to greyish-white in color. Lice present on other body parts covered by hair are not head lice but are either pubic lice ( Pthirus pubis ) or body lice ( Pediculus humanus humanus ).