We are getting approximately 100 children a day - and we could immunise more

Dr David Pugh, private GP

Some parents have gone as far as to take a day trip to the continent in order to have their children immunised by a French doctor.

Many parents who feel unwilling to allow their toddlers to receive the triple MMR vaccine - despite the vast majority of doctors believing it to be safe - still want to protect them against measles.

Nervous GPs

In all cases, it is a highly unpleasant infection, and in very rare cases, it can cause life-threatening complications.

The single measles vaccine is the only alternative to MMR, even though some doctors have cast doubt on its efficacy.

It is not available on the NHS anywhere to younger children - it does not have a licence because many doctors believe it does not actually work well enough.

The bulk of GPs providing the single vaccine are private GPs, who, until recently, were nervous about widespread publicity because of fears of harassment by health officials.

Dr Peter Mansfield, working privately from a practice in Louth, Lincolnshire, was reported to the General Medical Council, which regulates the profession, by a health authority.

Dr David Pugh - offers the jab

It claimed that the GP was acting outside the best interests of his patients by giving the single jab.

Dr Mansfield insisted that he was simply providing a service to parents who had no intention of giving their children MMR - in other words, it was the single jab or nothing.

The GMC decided that there was no case to answer and formally cleared him - effectively giving the green light to dozens of other GPs spread around the country to offer the single vaccine.

Cabin practice

One such GP is Dr David Pugh, who runs a private practice aimed at pilots from a temporary building on an airfield in Elstree, Hertfordshire.

Once word got around that he was offering the single jab, he was inundated with requests.

He said: "We are getting approximately 100 children a day - and we could immunise more.

"At the moment there is a three week waiting list, and it gives one an indication of the demand for a single vaccine."

There are ways of finding a private GP willing to give the single vaccine - special interest group Jabs offers email advice on doctors in each region at its website.