What Does a Baby Head Louse Look Like?

Head lice develop through three distinct stages. Knowing what each looks like makes identification much easier.

Nits (eggs) Nits are the eggs laid by adult female lice. They are oval, very small (about 0.8 mm long and 0.3 mm wide — roughly the size of a knot in thread), and firmly attached to the hair shaft near the scalp. They typically appear yellow or white, but live nits can sometimes take on the same colour as the child’s hair. Nits are usually found within 4 to 6 millimetres of the scalp. Eggs further from the scalp are either dead or have already hatched, because they need the warmth of the scalp to survive.

What to look for: Small, teardrop-shaped specks stuck to individual hairs. They do not brush or shake off like dandruff. If you run your fingers down a hair strand, a nit will not move.

Nymph (baby louse) When the egg hatches, a nymph emerges. This is the stage you are asking about. The nymph looks exactly like an adult louse but is smaller. Immediately after hatching, it is about 1 to 2 mm long. It will feed on blood from the scalp and grow over about 7 days, moulting several times, until it reaches adult size (2 to 3 mm, about the size of a sesame seed).

The nymph is tan, greyish-white, or light-brown. It has six legs with small claws adapted for grasping hair. It moves much more quickly than an adult louse, which makes it harder to spot.

What to look for: A tiny, fast-moving speck on the scalp or in the hair. It may appear to scurry away from light or comb teeth. Because of its colour, it can be difficult to see against light-coloured hair or a pale scalp.

Adult louse Adult head lice are about 2 to 3 mm long — again, about the size of a sesame seed. They are tan to greyish-white, with six legs. Female lice are usually slightly larger than males. Adults can live on a person’s head for about 30 days. They feed on blood several times a day and can lay up to 8 to 10 eggs daily.

What to look for: A sesame-seed-sized insect moving through the hair. It is light-coloured and may appear darker if it has recently fed. Adults are often easier to spot than nymphs because of their larger size, but they still move quickly.

Since baby lice are tiny, fast, and light-coloured, you will rarely see them by simply looking at the scalp. The most reliable method is wet combing with a fine-toothed detection comb. This approach is recommended by the NHS and various public health authorities.

Step-by-step wet combing method

Wash your child’s hair with ordinary shampoo and then apply a generous amount of conditioner. Conditioner stuns the lice temporarily and makes combing easier. Use a wide-toothed comb to remove tangles. Switch to a fine-toothed detection comb (available from pharmacies, supermarkets, or online). Start at the scalp and comb through to the ends of the hair. After each stroke, wipe the comb onto a white tissue or paper towel. Look for any moving lice — including nymphs — and for nits that have been dislodged. Comb every section of the hair from scalp to ends, at least twice. If you find live lice, repeat the process every three to four days for at least two weeks. This breaks the hatching cycle because any nymphs that hatch after initial treatment are removed before they can lay new eggs.

Why the comb works better than looking: A nymph is about 1 mm long and moves at about 23 cm per minute. The conditioner slows it down, and the fine comb physically catches it. The white tissue makes the pale-coloured louse visible.

A common mistake is confusing nits or baby lice with dandruff, hair casts, or product residue.

| Feature | Nits / Lice | Dandruff | Hair casts | |--------|------------|----------|------------| | Attachment | Firmly stuck to the hair shaft | Loose on the scalp, flakes off easily | Cylindrical, can slide along hair | | Appearance | Oval, uniform, small | Irregular shapes, white flakes | Thin, white, tube-like | | Location | Close to scalp | Scattered across scalp | Often near scalp but can move | | Removal | Requires fine comb or fingernail pull | Brushes out easily | Slides off when pinched |

Baby lice themselves are always moving. If you see something that does not move and is attached, it is likely a nit. If you see something that moves, even slowly, it is a louse — nymph or adult.

Finding a single baby louse means there is an active infestation somewhere on the head. It suggests that a female louse laid eggs that have already hatched, and more may be present.

Treating head lice at home The NHS recommends wet combing as the first-line treatment. It is effective, does not contribute to insecticide resistance, and carries a low risk of skin irritation. If you prefer a chemical treatment, lotions and sprays containing dimeticone or permethrin are available from pharmacies and supermarkets. Always follow the instructions carefully.

Important points from UK guidance

Check all family members. Head lice spread through head-to-head contact, so anyone in the household with hair should be checked. Treat only those with live lice. Do not treat as a precaution; there is no evidence it prevents infestation. After treatment, continue to comb with conditioner every three to four days for two weeks to catch any newly hatched nymphs.

School and household management If your child has head lice, they do not need to be sent home early from school. According to current public health guidance, the child can stay until the end of the day. Provide the school with a note informing them. The child can return to school the next day after treatment has begun.

There is no need to wash bedding or clothes excessively. Head lice cannot survive for more than one or two days away from a human scalp, and they only transfer through direct head-to-head contact, not from hats, pillows, or furniture. A normal wash cycle is sufficient. Avoid using insecticide sprays on bedding or furniture — they are not necessary and can be harmful.

Preventing reinfestation

Encourage children not to share combs, brushes, hats, or hair accessories. Regularly check hair using the wet combing method, especially during outbreaks at school. Keep a fine-toothed comb in the shower and use it weekly as a habit.

Most cases of head lice can be managed at home. You might consider professional services if:

You have treated the hair thoroughly at least three times with wet combing or a licensed treatment, and live lice are still present. You are unsure whether you are dealing with lice or another scalp condition. Your child has a severe skin reaction or secondary infection from scratching.

In the UK, several clinics and pharmacies offer head lice checks and removal services. A professional can confirm the diagnosis, show you what to look for, and help with stubborn infestations.

Use this answer as one piece of evidence, not the whole decision. If you want a quick second check, start with the AI head lice checker, then compare your result with the wider AI Detection hub so you can see where this question fits in the bigger picture.

If what you are seeing still overlaps with common lookalikes, compare it with what do head lice look like in hair and what do nits look like on hair shafts before moving to treatment on guesswork alone.

When the evidence remains mixed after a better photo or repeat check, move from uncertainty to confirmation. The most practical escalation routes are How to Choose a Head Lice Clinic Near You and the Head Lice Clinic Locations hub.

If active lice becomes likely, use the shop treatment reviews and the review of the NitNOT Fine Tooth Comb as decision support rather than treating every doubtful sign automatically.