What are head lice?

Head lice are tiny, wingless insects about the size of a sesame seed that live in the hair of humans. They feed on blood by biting the skin. Their eggs are called nits and are laid in the hair. The nits hatch after several days, producing more lice.

Lice and nits are not dangerous, and do not spread disease, but the bites can cause itching, can be uncomfortable, and sometimes can cause skin irritation.

Should I keep my child home from school?

There is no requirement to keep children home from school or child care as long as effective treatment begins before the next day of school or child care.

How are head lice spread?

Head lice can be passed between people (most often children) by contact with personal items, for example shared combs and brushes.

The spread of lice among preschool and school children is common, and is not a sign of poor hygiene.

Lice need warmth and blood to survive. They do not live for long on furniture, hats, bedding, carpet or anywhere else in the environment.

What are the symptoms of head lice?

Lice can often cause the skin to become itchy, but this is not always the case. Bites can cause symptoms such as redness and irritation, which can be made worse by scratching.

You can see the lice and nits if you look closely at the head and scalp. Nits look like tiny white dots attached firmly to the hair. They cannot be brushed or flicked off the hair, but must be physically removed with fingers, fingernails or special nit combs.

How do I know if my child has head lice?

Your child will not always have an itchy scalp if they have head lice. Similarly, an itchy scalp does not always mean that your child has head lice.

The best way to check your child's hair for lice is to follow a weekly routine of scalp and hair examination. Use the following guide for a thorough check:

1. Using a normal comb, spread hair conditioner through your child’s dry, untangled hair. The hair conditioner briefly stuns the lice to make them easier to catch (lice usually move very quickly, so you might not see them without this step). Thick white conditioner makes it easier to see dark lice and eggs.
2. Using a special metal fine-toothed nit comb (available from a supermarket or pharmacy), comb sections of hair from the roots to the tips, making sure you comb the entire head. Nits and lice become trapped by the fine teeth of the comb.
3. Wipe the conditioner (and lice and nits) from the comb onto a paper towel or tissue.
4. Examine the tissue and the comb for any sign of lice and nits.
5. Repeat the combing process twice over on each part of the head.
6. If lice or eggs are found, you will need to use treatment to get rid of the head lice.

What is the best treatment for head lice?

The most effective treatment involves repeating the hair conditioner and combing process every day until no head lice have been found for at least 10 days. This covers the time it can take for any undetected nits to hatch into more head lice.

You might need to use your fingernails to remove any nits from your or your child’s hair that escaped the comb and that are 15 mm or less from the scalp. Because nits need warmth to stay alive, any that are further away will not hatch — they will be dead or will have already hatched.

The advantages of the hair conditioner and combing process are that it is not expensive and avoids the use of strong chemical pesticides on your or your child’s skin.

How effective is a chemical treatment of head lice?

There are chemicals you can buy at the chemist that kill head lice that are safe for children over 6 months of age. However, there is no single chemical treatment that will work for everyone, as lice can develop resistance to the chemicals.

If you decide to use a chemical treatment, it is important that you closely follow the instructions that come in the package. You will need to repeat the chemical treatment within 7 to 10 days, as most treatments do not kill the eggs. The only way to test whether the treatment has worked is to use a nit comb and look for any live lice. If it has not worked, do not use the same chemical again. Instead switch to another chemical treatment or use the comb and conditioner method.

What can be done to help prevent lice?

It is difficult to prevent head lice. Lice move between children (or adults) by head-to-head contact during play and can survive for some hours on combs and brushes. One step to minimise the spread of head lice is to avoid sharing brushes and combs.

There is no evidence that chemical or herbal products can keep head lice away. Some people think that having clean hair can prevent head lice, but the truth is that head lice are attracted to hair, whether it’s long or short, clean or not.

Resources and support

• NSW Health has information on choosing the right head lice treatment.
• Check out the NSW Health Nitbusters Programwhich includes tips to reduce the spread of head lice in the community. 
• Read the SA Health quick graphic guide to how to get rid of head lice using the combing method.
• Call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to answer your questions 24 hours a day, 7 days a week.