The Medicines Control Agency (MCA) has outlawed the importation of older, single-dose measles and mumps vaccines on "safety grounds".

The BBC's Richard Hannaford reports: "Campaigners say the government is acting the bully"

It has refused an application by drugs company Idis to import the old vaccines into the UK, following parental demand sparked by research two years ago which linked MMR to autism.

A string of recent studies, however, showed that such a link does not exist.

Single jabs 'don't work'

The BBC's Richard Hannaford: "Reluctance to use MMR has led to warnings of a measles epidemic"

The Department of Health said there was growing evidence that the single-dose mumps jab did not work, and that both the mumps and measles jabs were unlicensed because the manufacturers had allowed them to lapse.

"Under law, unlicensed medicines should not be imported when a safe and effective licensed alternative is available," it said.

Measles epidemic feared

The move is being seen as an attempt to stop the drop-off in parents taking their child for the MMR vaccination.

MMR is a safe and effective vaccination, most doctors insist

Some parents have been so worried about the possible side-effects of MMR that they have either turned to the single-dose alternatives or simply refused to let their children be immunised.

This in turn has brought warnings from public health officials that by 2002 a new measles epidemic could threaten the country.

The Public Health Laboratory Service said earlier this month that only 87% of babies were being given the triple vaccine by the recommended age of 16 months, against the 95% needed to keep immunity levels high enough to safeguard against epidemic.

Unlicensed but available

The medical establishment believes that MMR is safe and effective.

Although some doctors have been willing to prescribe the single-dose vaccination on the NHS in the UK, many say they have done so reluctantly, under parental pressure.

But supporters of the single dose believe that it avoids the risks posed by the "cocktail" effect of the MMR jab, which is given on two occasions - in early infancy and a booster before the age of five.

And even if the single doses are banned in Britain, it is possible that parents will still be able to get them.

Although unlicensed in Europe, they are widely available, and some parents have reportedly been organising trips to France where a single-dose vaccination has been offered by doctors for £18.