Education: Combing the country for nit-pickers: Next week throughout Britain, schools will declare all-out war on headlice. Wendy Berliner reports

Next Monday night, on Halloween, thousands of children all over the country will be hunting bugs, rather than spooks, in the largest single onslaught against headlice in schools.

In an attempt to get to grips, at least temporarily, with what is one of the most common public health problems, about 2,600 schools will take part in 'Bug-Busting', a co- ordinated hunt for headlice in bathrooms around Britain.

No one really knows how many new cases of headlice occur each year. The most modest estimates run into tens of thousands, while some experts suggest 2.5 million cases are nearer the mark.

But one thing is certain - headlice are not harboured just by the poor and dirty. They feed on scalp blood, and any head will do, no matter how privileged.

In fact, Ian Burgess, deputy director of the Medical Entomology Centre at Cambridge University, and one of the world's experts on headlice, believes the complacency of the middle classes is the headlouse's biggest ally.

'Lice are more of a middle-class disease these days. The fully aware, educated and articulate parents who don't think it's their problem are the basic cause of the continued lice problem in this country.

'Two working parents are the least capable of finding the time for the basic care to check for lice.'

Bug-busting was launched in 1989 in Hounslow, west London, in a handful of schools where the incidence of headlice had rocketed since the withdrawal of the 'nit nurse'. The idea came from a small charity called Community Hygiene Concern and this year it is being taken up by a record number of schools.

Joanna Ibarra, the campaign co- ordinator, says that a school can usually be free of lice until Christmas following bug-busting night. In the participating schools, children from four upwards will be sent home with a fine-toothed comb and a sheet explaining what to look for.

If the head is infected, the next stage normally would be to treat the head with one of the proprietary louse-killing lotions. But, according to Ms Ibarra, there is growing evidence that lice in some places may be becoming resistant to certain insecticides.

This, she says, is backed by the interim results of research at the London School of Hygiene and Tropical Medicine. But the claim is strongly denied by pharmaceutical companies, which blame improper use or failure to treat everyone in the household.

The lotions, which contain different pesticides, are recommended for use in rotation by local authorities to avoid the chance of lice becoming immune.

In cases where lotions do not appear to work, Ms Ibarra suggests washing the hair every two days for a fortnight and combing it when it is slippery wet to hook out adult lice and baby lice before they are mature enough to lay eggs. Then hair should be checked weekly in the same way.

She strongly disapproves of the advice of pharmaceutical companies to treat all the heads in the household if lice is found on any member. 'A person should be treated only if lice are found,' she says.

Twenty-five years ago, when some local authorities were still running 'cleansing stations' for children with head lice, there were three million cases a year. When there is an outbreak in a school, it tends to be follwed by a second, and sometimes a third, which leads parents, at least, to think there is an epidemic.

But the Department of Health stopped keeping figures in 1988 after years of declining numbers. Then there were 90,000 cases found by nurses in state-school children. This estimate may have been too low, however, because it is difficult to find headlice through cursory checks of dry hair that would have been possible in 'nit nurse' inspections.

Almost 3 million doses of louse- killing lotion are sold each year. Although there is evidence that some people pour it over the heads of themselves or their children 'just in case' they have lice, Ms Ibarra believes that approach accounts for only 500,000 of the doses sold. 'That makes 2.5 million cases a year,' she says.

At about pounds 3 for a typical bottle, it is big business. The market for the lotions has shrunk over the last year or so with about 300,000 fewer bottles sold, according to Ian Burgess. He says this may suggest that people are becoming better at checking for lice.

He believes an incidence of between 5 and 7 per cent headlice cases in the population, about 500,000 cases, is probably common - much better than other countries, he says. In France, for instance, incidence rates of between 5 and 15 per cent were common in the late Eighties.

Headlice are spread by lingering head-to-head contact of a minute or more - such as hugging. The creatures do not hop, jump or swim. Clean, short hair, unobstructed by dirt and grease, makes for a simpler crawl to the scalp. The peak incidence of headlice is between the ages of seven and 12.

They have been living on humans since before we stood upright. Most louse infections are small - the average is 10 lice - but serious infections left untreated can leave people feeling ill or 'lousy'. It can be so debilitating that their intellectual powers are affected and the unkind might call them 'nitwits'. Lice can be more than just a nuisance and an embarassment.

For a Bug-Busting pack, write to Community Hygiene Concern, 160 Inderwick Rod, London N8 9JT. For the helpline, call 081-341 7167.