Headlice: A guide to treating your child’s hair

Discover what makes those pesky critters tick

Factfile: Headlice

What are head lice?
Lice are wingless, greyish-white insects with flattened, elongated bodies and oval heads. They are 1.5mm to 3mm inch long.


Where can head lice be found?
Head lice spend their life clinging tightly onto our hair as soon as they hatch. They tend to stay close to our scalps, so they can feed on our blood; they cannot survive for long once removed from the head.

How do you get head lice?
Head lice move from one host to another during head-to-head contact. When your hair is touching someone else’s, even for a few moments, they can migrate. This is why they are prevalent amongst primary school children.

What are the signs?
Often there is no sign of infestation until nits – empty egg cases – start to become visible as they grow out in the hair. Not everyone itches. Use a fine-tooth comb to do a careful visual check for nits, eggs and head lice once or twice a week. Do this when you wash and condition the hair. If hair is dry, lice can move rapidly away from the area being examined.

How can you detect lice and nits?
It’s easiest with conditioner on the hair, as this immobilises lice. Section the hair and comb from the scalp downwards. After each stroke, check the comb for live lice. Fully-grown head lice are the size of a small ant, but newly hatched eggs can be as small as a pinhead. If you inspect dry hair, do so in good light. Look for eggs glued to the roots close to the scalp. If you find eggs or nits attached to the hair, then check all family members and use a comb to treat everyone who has lice, nits or eggs in their hair.

What is the difference between nits and eggs?
‘Live’ head louse eggs are glued to an individual hair strand as soon as they are laid. Nits are empty egg cases, which remain glued on the hair as it grows after the nymph lice have hatched. Nits are often the first visible sign of a head-lice infestation.

Where are the eggs found?
Female head lice attach each egg to the root of an individual hair strand close to the scalp, so that when they hatch they are close to their food source. Eggs found more than 1cm from the scalp will be nits, which remain glued on and grow out as our hair grows.

What do the eggs look like?
They are about the size of a pinhead, white to cream in colour and they look like a tiny teardrop fastened to the hair shaft.

Do lice prefer clean or dirty hair?
They’re not fussy, but it is easier for them to move in clean hair. Lice are tough, resourceful creatures. You can’t wash them out, and there is no scientific evidence to indicate that either washing or not washing the hair will prevent an infestation.


Do they prefer boys or girls?
Girls tend to spend more time than boys in head-to-head contact. They usually have longer hair too, which can make it easier for head lice to move from head to head. It’s rare for fathers to get head lice, so some experts believe they don’t like testosterone.