Obesity, binge drinking, and unwanted pregnancies: the young are battling for their health and losing. So where is the school nurse when we need her most? Maxine Frith reports

They were once a presence in every school, checking children for nits, monitoring their height and weight and giving the odd lecture on personal hygiene. But in the last 20 years, school nurses have become increasingly rare, despite the rising tide of social, physical and mental health problems they have to deal with. Nurses point out that they could and should be at the forefront of public health policies to reduce rates of obesity and binge drinking among young people.

Twenty years ago, almost every school would have a dedicated nurse. Now there are just 4.5 staff per UK electoral constituency. School nurses now have to cover several schools at a time with caseloads of many thousands of children, as well as trying to pick up vulnerable youngsters who have been excluded or who have dropped out of the education system.

The Royal College of Nursing (RCN) estimates that school nurse numbers need to double from their current level of 3,000 to 6,000 in order to deal with the problems that their members are facing.

Joy Winks, a school nurse in the west Midlands and a member of the RCN's school nurse forum, said: "At the moment, all we can do is prioritise and focus on the most vulnerable children because there simply are not enough of us."

Disturbing new figures from the Department of Health last week showed that 27 per cent of children aged two to 11 are now overweight or obese. Days later, David Hart, general secretary of the National Association of Head Teachers, told how schools are having to deal with five-year-olds who have such poor diets that they have no idea how to use a knife and fork at meal times.

Somewhat belatedly, the Government has realised that school nurses could be a weapon in the battle against the increasing bulge of the nation's children.

Pilot projects have been set up to reintroduce annual school medicals, where children are weighed and measured to record their development. But the old-style way of singling out fat children in weigh-in sessions in the school hall has been replaced with more subtle messages about food by school nurses.

While Jamie Oliver may be transforming school lunches in the kitchen, school nurses are using the classroom to feed children messages about healthy food. Ms Winks says: "We are using a resource where we take realistic plastic food into schools and talk to the pupils. The objects include everything from a glass of milk to chapattis and the idea is to get the children to make up a plate of food for dinner. Then we talk about what they have chosen and what kind of things they could choose. It is simple, involves the pupils and is cheaper than being in a kitchen and getting them all to cook."

Advice on healthy eating and exercise is just one part of the school nurse's role, but they are also uniquely placed to deal with some of the harsher lessons in growing up.

A recent survey of school nurses by the RCN found that two-thirds of school nurses said they frequently had to counsel children about alcohol and drug addiction. Nine out of 10 said they were routinely involved in providing advice on sexual matters, contraception and abortion.

Sexually transmitted infections among teenagers have doubled in the last 10 years, with more than one million diagnoses in the under-20 age group in 2001. While teenage pregnancies are falling overall, rates are still rising in the most deprived areas of the country. More than 1,000 girls under 14 had an abortion last year, a rise of eight per cent on 2003.

The right-wing press is fond of screaming headlines about school nurses handing out the morning-after Pill to barely pubescent girls without their parents' knowledge, culminating last year in the castigating of a school outreach worker for taking a 14-year-old girl to have an abortion without telling her mother.

But it is this confidentiality that is the key to the service and often acts as a bridge for young teenagers between keeping something secret and telling their families.

Ms Winks says: "I have been school nursing for 13 years and I have never been in a situation where I have not suggested to a young person that they talk to their parents about their problems, be it drug or alcohol or sexual-health problems. The vast majority of the time, they do talk to their parents, but it is very important that they know they are talking to us confidentially."

She adds: "Young people often see their GP as the family doctor who in the past they have gone to with their parents and it can be difficult for that relationship to change as they get older. We can point them in the right direction and show them how to access health services themselves, and show that they can trust health professionals."

But are these recent social changes or was the role of the school nurse ever really confined to nit checks and eye tests? Ms Winks thinks that the same social problems were present in the past but were either not noticed or simply swept under the carpet. She says: "Before, we would have the children lined up to do eye tests and there may have been three or four girls pregnant in the queue, but we weren't dealing with them."

Furthermore, in the wake of the damning public inquiry into the murder of eight-year-old Victoria Climbie, it was recommended that school nurses were actively involved in child-protection issues. But the problem, as ever, comes down to money.

School nurses are mainly funded by their local primary care trusts (PCTs), although some are paid for directly by local education authorities or the schools themselves. But many PCTs are facing multi-million deficits this year. The budgets for school nurses are not ring fenced and are therefore among the most vulnerable to cost cutting.

Nurses are now under such pressure that the most some can do is to leave their mobile number on school notice boards for pupils to contact them remotely. As Liz Allan, chair of the RCN's school nurse forum says: "We have to deal with children with complex needs, who have been abused and are vulnerable, but there are simply not enough of us to deal with everyone."