Head Lice – Lousy Little Parasitic Insects


Head lice (Pediculus capitis) are small parasitic insects well adapted to living mainly on the scalp and neck hairs of human host. These are mainly associated by direct head-to-head contact with an infected person's hair, but may infrequently be transferred with shared combs, hats and other hair accessories.

They get their nutrients by blood-feeding once or twice each day, and can not survive for more than a day or so at room temperature without ready access to human blood. These parasites can survive up to 30 days on a human holding on to hair with hook-like claws found at the end of each of their six legs. They are rarely found on the body, eyelashes, or eyebrows and rarely (if ever) cause direct harm, or transmit infectious agents from person-to-person. Head lice are equal opportunity parasites that do not respect socio-economic class distinctions and can infest people of all ages, but children are sooner to infestations because of their habit of playing in close contact, sharing hats, headphones, combs and brushes, sleeping bags , Stuffed animals, and clothing.


Head lice eggs are called nits and are laid by the adult female at the base of the hair shaft near the scalp and look sort of like dandruff, only they can not be removed by brushing or shaking them off. The eggs hatch about 7 to 11 days after being laid. Those further than 1/4 inch away from the scalp have probably already hatched. Nits are most effectively removed by combing the hair with a specially designed nit comb. The eggs will be distinguished from dandruff flakes as they are extremely adherent to the hair shaft, whereas dandruff can be easily moved along the hair shaft.


Contact with an already infected person is the most common way to get head lice. Less commonly, Weaving clothing, such as hats, scarves, coats, sports uniforms, or hair ribbons, recently worn by an infected person. There are four critical steps to controlling an infestation: the use of an effective head louse treatment; Nit removal from the head (combing); Removal of lice and nits from the household environment by vacuuming, washing, or freezing objects suspected of being infected; And daily head checks and nit removal until infestation is gone, followed by weekly head checks to detect re-infestation. The doctor should be able to tell you if your child is infected with lice and needs to be treated.


Treatment should be considered only when active lice or viable eggs are observed. A treatment can cause significant side effects in children younger than 6 months old, the elderly, and anyone weighing less than 110 lbs (50 kg), especially when it is used repeatedly over a short period of time. If your child is 2 years old or under, you should not use medicated treatments. Your child's doctor may recommend repeating treatment in 7 to 10 days to make sure all the nits have been killed and to avoid any risk of reinfestation. Treatments may be over-the-counter or prescription medications, depending on what has already been tried. It is not uncommon for treatments to be unsuccessful because of incorrect use or because the lice may be resistant to the chemical in the shampoo. Following the directions on the product label is also important to ensure that the it works correctly.

Medicated shampoos can usually kill the lice and nits, but it may take a few days for the itching to stop. Some don'ts include: Do not use a hair dryer on your child's hair after applying any of the currently available scalp shampoos, because some contain flammable ingredients. Do not wash your child's hair for 1 to 2 days after using a medicated shampoo. Be patient and follow the protocol and preventive tips as directed by your child's doctor for keeping the bugs at bay, and you'll be well on your way to keeping your family lice-free.

If you feel like you're following every recommendation and your child still has lice, it may be because of one or more of the following: there are still some nits left behind, your child is still being exposed to someone with lice, the shampoo You're using is not effective. If your child still has lice for 2 weeks after you started treatment or if your child's scalp looks infected (with pus or sores), call your child's doctor. Vacuuming the carpets, upholstery, and car seats will take care of any lice that fell off before treatment.


Head lice infect hair on the head and are more common in close, overcrowded living conditions. Infestation causes intense itching, but does not lead to a serious medical problem. They can be spread when infected hair brushes or combs are shared or when infested bedding, towels or shower caps are shared. Head lice is an increasing problem because lice-killing drugs are becoming less effective. Each year, between 6 and 12 million people worldwide become infested. Children ages 3-11 and their families became infested most often. Pets are of no significance in transmitting human lice, and should not be treated.

In one study, the estimated annual cost of infestations in the United States was nearly $ 1 billion dollars. Girls contract head lice more often than boys; Women more often than men. Anyone can become infected and the presence of head lice is not the result of unclean conditions. Although it can be challenging to eliminate, you must be patient and persistent when dealing with an infestation.