Head lice

Head Lice

What are head lice?

Head lice are flat-backed, greyish insects that live on human scalps. They are extremely common - most children will get them at least once or twice. Infestations are most common in children aged four to 11.

They feed by biting the scalp and sucking blood. The female head louse lays 5-8 eggs per night and glues them to the base of the hair, close to their food source (blood). These eggs are nits and look like small shiny white bumps on the hair. The lice hatch in about ten days, but the egg case is left behind to grow out with the hair.

Those affected will usually complain about constant scratching - this can lead to disturbed sleep and associated problems such as irritability and poor concentration.

How are they spread?

Head lice are spread by head-to-head contact lasting 30 seconds or longer.

Head lice do not jump or fly. They creep from one head to the next and need to be near the skin to survive. Infestation with head lice does not indicate a lack of hygiene - lice have no specific preference for clean or dirty hair.

An average infected head has around 10 lice. If left untreated, this can rise to 20 lice.

Lice cannot be spread by towels, bedding, clothes, furniture, pets or brushes.

How are they detected?

According to the Department of Health, wet detection combing once a week is the best preventative method against head lice.

A fine detection comb should be used and some people find a magnifying glass can make detection easier. A white plastic comb should be used for detection (metal combs are used for removing nits).

Particular attention should be paid to the nape of the neck and behind the ears as these areas are warm and sheltered.

The hair should be clean, wet and tangle-free. Combing the hair over white paper is recommended as any removed lice will easily be seen.

How should I carry out detection combing?

-The hair should be washed using ordinary shampoo and towel dried until it is damp but not dripping wet.

-An ordinary or wide-toothed comb should be used to untangle the hair.

-When the comb is able to move freely through the hair, a plastic fine tooth/detection comb should be used to begin the detection.

-The comb should be used so that the teeth are touching the skin of the scalp at the top of the head and then drawn through carefully to the edge of the hair.

-After each stroke, the teeth of the comb should be closely checked for lice.

-This should be repeated all the way around the head. This is a lengthy process and if done correctly, can take as long as 15 minutes depending on the length of the hair.

How can I get rid of head lice?

Regularly examine your children's scalps - look for nits close to the skin, behind and above the ears and on the back of the neck. You may see spots of blood, or scratched areas on the scalp.

It is no longer recommended or required for all family members to be treated with insecticides if one member of the family has head lice. Only those in which a living, moving louse have been observed should be treated. Detection combing should be used on all family members to determine this.

Where someone does need to be treated, chemical insecticides should be used as these are the only treatment that have proven to be effective against lice when applied correctly.

These can be obtained at your local pharmacy. Ensure you follow the instructions carefully.

What are the possible causes of treatment failure?

Where treatment does not appear to work, the main reasons for this are:

-Poor application methods, e.g. inadequate or incorrect usage of insecticide.

-Re-infection due to a failure to diagnose or to treat others also infected.

The best way to prevent re-infection is to treat all those infected at the same time.