Children often pick up lice at playgroup, nursery or school – this article tells you what lice are, how they might be picked up and about treatments.

If your child is now at playgroup, nursery or school, you are probably aware that head lice are everywhere. Head lice don’t respect class, age, gender or even good hygiene. They will appear wherever conditions are right for them. The more you understand about head lice and how the various treatments for head lice work, the more you will be able to keep them under control in your family.

What are head lice?

Head lice are tiny parasites that can grow to around the size of a sesame seed. They are a range of colours from almost transparent to a reddish brown colour. They start life as an egg that is attached to the base of the hair shaft with a very strong ‘glue’ that sets rock-hard. The egg hatches after six or seven days, producing a nymph that will go on to shed its skin three times before becoming a mature adult louse, capable of mating. This process takes nine days. Between each shedding of the skin, the young louse feeds on the blood through the scalp of its host. They feed up to six times a day – they are full of blood, which is why they look reddish brown.

How do I know if my children have head lice?

Most people make the mistake of thinking that itching is the most reliable sign of head lice. Itching is caused by an allergic reaction to the substance the louse injects into the scalp when it feeds. This substance dilates the blood vessel and stops the blood from clotting. In fact, only one in three people are sensitive to this substance, so the majority of people have no symptoms of itching. It’s also true to say that by the time your scalp feels itchy, you will have had lice, usually for about three months.

The best way to detect head lice is by washing the hair and then combing through some olive oil. Many people use hair conditioner, but this can be excessively foaming, making it difficult to see the lice.

Use a fine-toothed comb and separate small sections of hair starting at the scalp. Inspect the comb and wipe on a tissue. If you find a moving louse, there is an active infestation. It is extremely difficult to remove any of the eggs in this manner, so if you do find what looks like a white egg, this will almost certainly be an empty egg case or ‘nit’.

Live eggs are only found at the base of the hair and are almost colourless, whereas nits are white and move with hair growth further along the hair shaft. If you find only nits, this is a sign of a previous infestation and does not require any treatment. It’s important that you only use a head lice treatment if you find a live, moving louse. You must also check the whole family for head lice and treat anyone else with a confirmed case of the lice at the same time.

How do you get lice?

Head lice spread only by ‘head-to-head’ contact. You cannot catch them by sharing hats or brushes. Lice cannot fly, jump or swim, but literally walk from one head to another. They have special claws that enable them to grasp the hair very tightly, so they cannot fall off the head either.

Lice like the very warm and humid conditions next to the scalp and will not willingly stray very far unless it’s to move to another nice warm head. It is mainly children between four and 12 that get head lice. Girls get them more than boys as they tend to touch heads more often during play.

Can I stop my child from getting head lice?

Prevention is very difficult, but you can encourage children not to make head-to-head contact with others. Older children will understand this. However, the best way to keep head lice under control is to check the whole family for lice every week, and to use an effective treatment when necessary. Don’t wait until the school sends home a letter before you start checking for lice.

What treatments are available?

Treatments fall into two groups – wet-combing to remove the live lice and insecticide treatments to kill the lice.

Wet combing
This is suitable only for those people who are very determined to get rid of the lice, as it takes two weeks of combing before the infestation can be cleared. Use a fine-toothed comb and comb the hair in sections as described above. Combing cannot get rid of the eggs, so you must do it every three or four days until you have done it at least four, but preferably five, times. A word of warning – it’s hard to get small children to sit still long enough to do wet-combing properly and they can also get quite distressed if it’s done too harshly.

Insecticide treatments
These are available from pharmacies. They work by actually killing the lice and some can also kill the eggs. The main difference in insecticide treatments is the type of insecticide they contain and the length of time the treatment takes, which can vary from 10 minutes to 12 hours.

Ask your pharmacist for advice on which treatment is best for you and your child. Treatments are available that are suitable for asthmatics and for people with sensitive skins. Always follow the instructions very carefully.