A school in Kent decided to screen pupils for asthma - 20 children and their parents were glad to discover the truth. By Rita Carter
This week's PE lesson for the youngest class at Bidborough School in Kent has an extra exercise thrown in. Before and after their usual skipping, bouncing, hopping and ball-throwing, the children have to blow, as hard as they can, into something rather like a bicycle pump.

To the pupils, it's just an extra bit of fun, but the purpose of the blowing game is deadly serious and might even, indirectly, save the child's life. The pump is a peak-flow meter, which measures lung strength, and the children are among the first in the country to be routinely screened - courtesy of their school - for asthma.

For every asthmatic diagnosed, another one is thought to go unrecognised. But ignorance, in this case, is not bliss. Children with undiagnosed asthma typically miss 20-25 school days per year through illness; they suffer continual coughs, colds, sluggishness and general ill-health, and many take courses of useless and potentially harmful antibiotics to cure what seems to be a catalogue of minor infections. Furthermore, there is a risk, though slight, that an asthma attack could kill an undiagnosed child before anyone realised what it was.

Once a child is known to be asthmatic, however, preventative treatment, usually by inhaler, can do away with the perpetual ill-health by damping down the airway inflammation leading to asthma attacks.

The degree to which asthma remains undiagnosed in children was uncovered three years ago by a research team led by Surrey GP Dr Deryk Williams. They tested all 237 children at a state school in Weybridge and found that apart from the 22 known asthmatics, the screening showed up a further 19 whose parents has no idea that they had the condition.

This helped to raise awareness about asthma, but Bidborough School is the first to act on it in a direct way. Last year, one of the school's governors heard about Dr Williams's work, and suggested the teachers and parents could do for themselves what his team did in Weybridge - screen the entire school.

"I was not too keen at first," says headmistress Catherine Thewlis. "I wanted to be absolutely certain that it would not be detrimental to the children. But the parents were really enthusiastic about the idea and more or less organised it themselves."

All 210 pupils at the school were screened for the first time last year and the result was exactly as Dr Williams had predicted - on top of the 20 known asthmatics, they found 20 more. This year, and in future, the school will screen all new pupils.

One of the children whose asthma was recognised for the first time was the daughter of Carolyn Saxton, the school's deputy headmistress.

"Lucy used to get what we thought was bronchitis - a chest cough we assumed was caused by infection," she says. "Looking back, the main sign of asthma was her bark. Lucy has always been a keen swimmer and she was in the school squad. But after a few lengths, she would give out this bark - it was like a sea lion - and people used to get really alarmed. The swimming supervisor called her out of the water several times because it sounded as though she was in real trouble."

In fact, Lucy was still able to breathe - but the airway restriction that made her bark was in fact mild asthma, as the school screening revealed. Lucy's GP confirmed the diagnosis, and gave her an anti-inflammatory inhaler which, used before exercise, prevents the airways becoming restricted.

"When Lucy is going to do something athletic, she takes a puff and knows she can do it with confidence," says Mrs Saxton. "She is going riding today, for example, and really looking forward to it. Before, she would still do it - but she would worry about getting breathless."

Most of the other 19 newly revealed asthmatics have also been given preventative treatment by their GPs. "We didn't tell the parents what to do," says Mrs Thewlis. "We just invited them to come and get the results of the screening and do what they thought fit.

"Every parent came to get the results, and most of the children who had suspect peak flows have since been seen by their own doctors. The children seem perfectly happy to be diagnosed - we haven't had any tears or traumas, and the parents ensured the whole thing went like a military exercise."

One reason so many children do not get recognised as asthmatic is because the illness is in some ways difficult to diagnose. "A parent may suspect something is wrong, but by the time the child comes to the surgery, she or he may seem to be perfectly all right," says Dr Williams, co-author of a guide to asthma published this month. "You can look back through the records and see this catalogue of coughs and colds and suspect asthma, but it is difficult to be sure. Screening is usually impossible in a surgery setting because you need to do peak-flow tests before and after exercise - and having a six-year-old child rushing around the waiting room doing vigorous exercise is just not on."

'Asthma: The complete guide for sufferers and carers' includes advice on creating asthma awareness in schools. By Dr Deryk Williams, Anna Williams and Laura Croker. Published by Piatkus, price pounds 8.99. COULD YOUR SCHOOL DO IT? Bidborough had a core team of three organisers, plus 30 other parent volunteers to help with the screening and a doctor and senior nursing officer were in attendance. Children were screened over the course of one day, at 10-minute intervals, in groups of 10. Parents helped them with the blowing and checked the results. The children each gave three blows before they started exercising, a further three blows after five minutes of PE, and a final three blows after five more minutes of exercise.

The peak flow meter measures the speed at which air comes out of the lungs: the faster the air comes out, the less the narrowing of the airways. With the Bidborough children the difference between the initial "at rest" flow reading and the after-exercise reading was noted. A difference of more than 15 per cent was considered suspect.

The screening should be carried out under medical supervision because there is a small risk that the exercise involved may actually trigger an asthma attack.

Bidborough School parents may be prepared to help other schools that want to set up a similar project. Contact Mrs Thewlis, Bidborough Primary School, Spring Lane, Bidborough, Kent.

Clement Clark International, which makes peak flow metres, is prepared to consider loaning equipment. Contact Victorine Hamilton on 01279 414969.