Children can pick up all sorts of undesirable things from school; naughty words, bad habits and, top of every parent's hate list, head lice (you're already itching as you read this, aren't you?).

Check your children's hair regularly. The easiest way is to comb the hair carefully over white paper, on the look-out for the lice's empty egg cases - otherwise known as the dreaded nits. The lice themselves are harder to spot, brown or grey wingless insects, barely the size of a match head, that lurk at the roots of the hair.

If your child does have head lice:

• don't panic. Head lice don't spread diseases or pose any serious health threat. Often they don't even cause itching.
• don't blame yourself. Head lice are not a symptom of dirty hair. For all their faults, they are democratic little beasts, who don't differentiate between clean or dirty hair, or care about its colour or its length. Nor do they discriminate on grounds of class, race, gender or even age. The only reason that primary school pupils are particularly vulnerable is that they are more sociable than the rest of us. They literally get their heads together more often, giving lice the opportunity to migrate from one scalp to another.
• don't worry. Pediculus humanus capitis is no match for a parent who takes quick and decisive action.

What to do
There are two basic strategies and a combination of both is probably a sensible approach:

• Wash your child's hair in one of the proprietary lice-killing shampoos available at any good pharmacy.
• Go on a louse safari. Apply plenty of conditioner (which slows the lice down) and comb the hair from the root upwards with a fine nit comb (the pharmacist will sell you one). Destroy any wildlife you find. Repeat this cull every couple of days until you've solved the problem.

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