A hayfever vaccine that has been out of use because of safety fears has been proving successful in an eight-year trial.

The grass pollen vaccine was withdrawn from general use following the deaths of patients who suffered an extreme reaction to the injections.

But doctors at London's Royal Brompton Hospital say there is no need for concern if the treatment is given by specially trained clinicians.

They say their success offers hope to the 500,000 sufferers who do not benefit from other current remedies.

Treatment increasingly available

Dr Stephen Durham, a consultant at the hospital, said: "There are probably half a dozen major centres around the UK where this form of treatment would be available.

The vaccine went out of use following deaths

"But the good news is that NHS Executive has recently approved allergy as a specialty, so so we should see more doctors in the future trained in allergies and able to offer this treatment more widely."

The treatment consists of monthly injections of 1,000 times the amount of pollen to which the average sufferer would be exposed each summer.

This spurs the body's immune system into action and protects the patient from an allergic reaction.

The Royal Brompton's programme has followed the progress of 47 hayfever sufferers over eight years.

Dr Durham said that the treatment was widely used for thirty years but fell out of use following the deaths of several patients.

However, he said such cases were extremely rare and there was little danger if the injections were given in a specialist unit.