Your head lice questions answered

Most families have some experience of head lice but do you know much about how they spread and how to battle an infestation? Here’s everything you need to know.

What do head lice do?

They feed on human blood. They leave tiny red spots that itch intensely. The female lays a daily batch of eggs (nits) which are attached to hairs close to the scalp. They hatch in about seven days and can live up to several weeks.

How do you catch them?

You can catch head lice if your hair touches the hair of someone who already has them. But as they move slowly contact needs to occur for about half a minute – they cannot jump, fly or swim, but walk from one hair to another.

Can my dog or cat catch them?

No. Head lice affect only humans and cannot be passed onto or caught from animals.

Can adults catch them?

Head lice are common in schoolchildren, particularly between the ages of four and 11, but anyone with hair can catch them.

Can I avoid them if I keep my hair squeaky clean?

They don’t mind whether your hair is clean or not. It is a misconception that head lice infestation is as a result of dirty hair and poor hygiene. In fact clean grease-free hair makes it easier for lice to cling on. They can be found in all hair types, long or short, and in hair of any condition.

How can I tell if I have them?

You will know if you have head lice if you find a live louse in the hair. Having nits (the shells of lice eggs) is not a sign that you have head lice.

How do I get rid of them?

There are a number of chemical treatments that can work well but head lice are increasingly becoming resistant to them, so repeated treatment is frequently necessary. You shouldn't use head lice treatments unless you know for certain that you have head lice.

Sometimes complementary therapy treatments such as tea tree oil are recommended for treating head lice, but their effectiveness has not yet been proven.
You might wish to try removing the head lice with a special comb. After washing the hair apply conditioner liberally. Comb the hair through with a normal comb first, and then a fine tooth nit comb. Comb from the roots along the complete length of the hair and after each stroke check the comb for lice and wipe it clean. Work methodically over the whole head for at least 30 minutes and then rinse the hair as normal. You should repeat every three days for at least two weeks.

Why are they so difficult to get rid of?

Because of their size, re-infestation rate, life cycle, and their ability to develop immunity to insecticides. Lice can be a persistent and recurring nuisance, so it is important to treat them quickly and thoroughly.

Are chemical treatments safe for everyone?

You should always ask for advice before using medicated lotions on young babies (under six months), pregnant women or people with asthma, or allergies, and always read the instructions carefully.