Facts About Hair Lice

Hair lice, which are actually head lice, are pinhead-sized, parasitic insects that live on your head and feed on your blood. Lice are very common in schools and other group settings because they spread by close contact with someone who is already carrying lice. Lice find their way onto all types of heads; infestations have nothing to do with personal cleanliness, geographic location or living conditions. The most important preventative measure is to avoid close physical contact with anyone who has lice Understanding the needs and habits of head lice will help you avoid infestation and treat them properly if you do become infested.

Lifestyle

Head and hair lice enjoy the temperature, conditions and access to food (blood) on the human scalp, so it is rare to find them anyplace else. They do not live on pets and they do not survive long on any household items or inanimate objects. Head lice are not the same insects as body lice and pubic lice, which prefer to live elsewhere on the body and are often found in the seams of clothing.
Head lice cannot fly or jump but they move easily from one scalp to another via close physical contact between people. It is difficult to prevent the spread of lice in any situation where people are constantly in close contact. That is why "lice checks" are routinely performed on the heads of children in many elementary schools.

Reproduction

Head lice lay eggs, called nits, and attach them to strands of hair close to the scalp. Nits are yellowish-white and oval in shape. They can be difficult to see, especially in light-colored hair, because they look like dandruff or flakes of dried gel or other hair products.
After about a week, nits hatch into nymphs, or immature lice. Nymph lice must feed on blood to survive to adulthood. As adults, lice look like a grayish-white sesame seed with legs. They are difficult to see in any color hair. Adult nits must feed regularly on blood to survive their 30-day average lifespan.

Infestation

Although lice can't live very long off the human scalp, they can survive up to two days without blood, which is long enough to be transferred from one head to another via hats, scarves, coats, and other clothing and accessories. It is also possible for them to fall off a human and live briefly on furniture, rugs, bedding and bath towels.
When treating head lice, it is important to destroy adults, nymphs and nits, for the obvious reason that any young adults or eggs left behind are likely to cause a re-infestation. They can be destroyed by one of several over-the-counter (OTC) treatments in the form of solutions or shampoos available in almost every drugstore. The most effective OTC products contain pyrethrin (brand name Rid) or permethrin (brand name Nix). If OTC products do not successfully destroy lice and eggs, prescription shampoos, lotions, and other stronger, topical treatments are available. Non-toxic treatments that may help rid hair of lice and nits include running a fine-tooth or nit comb through wet hair repeatedly for at least two weeks. Some people coat the hair with a cream rinse or conditioner before combing.
Lice can and will return if not treated properly and completely. One lice have been found, it's important to do periodic checks to be sure there is no re-infestation.