Head Lice, image from www.entnemdept.ufl.edu

Head lice are tiny whitish insects the size of a sesame seed. They live on the scalp and hair shaft of humans where they feed on blood and lay their eggs called nits. Usually head lice do not cause serious health problems, but they can be annoying. The female louse can lay up to ten eggs a day for up to forty days. That’s a lot of nits crawling around and feeding on blood. Their feeding action causes a lot of itching and excessive scratching may lead to a bacterial infection.

How do you get head lice?

It is important to realize that a visit from head lice is not because you or your children are dirty, unwashed, or not cared for. The little buggers show no discrimination for social class or wealth. As many as 6 to 12 million people worldwide are infested with head lice. They do not fly or jump, but can move very quickly because they possess specially adapted claws that allow them to crawl and cling firmly to hair. The most common mode of travel for these parasitic insects is the sharing of hats, brushes, combs, or pillows and Close head to head contact. Kids are most prone to catching lice because they tend to have close physical contact with each other and often share personal items.

What are the symptoms?

Head lice Image from www.treehugger.com

The most common symptom of lice infestation is itching. Excessive scratching of the infested areas can result in sores which may become infected. Some children may also have a red, hive like bumps on their scalp. Close inspection of the head may or may not reveal the presence of live lice. The nits are often the only visible evidence of a lice infestation.

Treatment 

The number of human louse infestation has increased worldwide reaching hundreds of millions annually. There is no product or method which assures 100% destruction of the eggs and hatched lice after a single treatment. However, there are a number of treatment protocols that can be used with varying degrees of success. 

OTC treatments 

There are various over the counter (OTC) treatments which can be used for eradication of head lice.   

Pyrethrin

(e.g., R & C shampoo and conditioner), an insecticide, is an extract from chrysanthemum. This insecticide causes the central nervous system of lice to go into overdrive, killing them within ten to twenty minutes, along with75 percent of their unhatched offspring. Apply enough to thoroughly soak the hair and skin of the infested area and adjacent hairy areas. Allow it to remain on the area for 10 minutes then rinse  thoroughly and towel dry. Remove dead lice and nits with  a metallic nit comb. Treatment should be repeated after seven days.

Permethrin

(e.g., Nix cream rinse, Kwelleda-p crème rinse) is also an insecticide. It is a synthetic pyrethrin which  has similar activity like pyrethrin except that it remains effective for a longer period of time. It is applied to hair that has been pre washed with a conditioner free shampoo and left on for ten minutes after which the hair is rinsed and towel dried. Treatment should also be repeated after seven days.

Resultz– This is a new OTC head lice treatment containing 50% isopropyl myristate.  It is different because it does not contain any traditional insecticide. It kills lice by dissolving the wax that covers the exoskeleton causing subsequent dehydration and death. Its application is similar to that of other shampoos and it is applied to dry hair. All other protocols remain the same.

Prescription treatments

In some cases of resistant lice, some paediatricians have tried using TMP/SMX (septra) with permethrin (Nix). It has been found that this combo works better than either agent alone. The lice ingest TMP/SMX from blood in the scalp and this kills the nutrient-producing bacteria that live in the lice.

Other forms of treatment

 Suffocation– based treatment– A trial a few years ago with cetaphil skin cleanser applied to dry hair and blow dried seemed to have some efficacy. The lotion was applied once a week until cure was achieved, up to a maximum of three applications. For each application the patient applied the lotion thoroughly, and after two minutes combed the hair and dried the hair with a blow drier. Participants were instructed not to wash the hair for at least eight hours. Parent satisfaction was high, reporting a 50% reduction in the work and time associated with this therapy, and most importantly, no adverse reaction was reported.

Robi Comb– This is a battery operated comb with metal teeth. When drawn
through the hair it makes a humming sound until a louse is detected between two adjacent teeth. The hum stops and the louse are zapped to death by a small electric charge. The comb does not kill nits and the user still has to physically remove dead lice and nits.

Preventing reinfestation-Examination of your Childs hair periodically using a louse comb allows early diagnosis which makes treatment easier. In times and areas when louse infestations are common, weekly examinations of your child will aid control. Treating your child’s hair with 2-4 drops of concentrated rosemary oil every day, before he or she leaves for school or kindergarten will prevent new infestations. The oils can be combed through the hair using a regular comb or brush. Clean any items which are in direct or in long contact with the head (e.g., hats, pillowcases, brushes, and combs) Methods that kill lice and nits on an object include washing the item in hot water (66 degrees c), drying it in a hot dryer for 15 minutes, or storing it in an airtight plastic bag for 2 weeks.