The UK health secretary Jeremy Hunt is advising unprotected children and adults in England to have the MMR vaccine as the measles outbreak in Wales continues unabated.

Hunt said: “Today I am urging all parents, anywhere in England, who did not get their child vaccinated with two doses of MMR because of scare stories a decade ago to contact their GP surgery and make an appointment.”

The call comes as cases of measles in Swansea, south Wales, has reached 765 cases, and has now officially been designated an epidemic.

Health officials have set up emergency vaccination centres in the country to help offset the increase, but are warning that there may be fatalities the longer people do not have the inoculation, with children particularly at risk.

The fear is that the epidemic could spread across the Welsh border into England, which has prompted the health secretary’s calls.

Health officials said there had been an increase of 72 cases in Swansea since last Thursday, with 77 people having been hospitalised since the start of the outbreak in November last year.

Disgraced MMR paper - or govt 'behind the curve'?

One of the reasons parents have been reluctant to give their children the MMR vaccine is because of a 1998 Lancet paper from Dr Andrew Wakefield – which has now been fully retracted by the journal – purporting to show a link between the jab and autism and other conditions.

Hunt said: “Disgraced doctor Andrew Wakefield’s discredited and inaccurate research caused great harm to the MMR vaccination programme and led to thousands of parents choosing not to vaccinate their children against measles, mumps and rubella.”

But the Welsh government has also been blamed for reacting too slowly to the epidemic by Conservative Opposition party,

First Minister Carwyn Jones faced questions about the outbreak in the Senedd on Tuesday. He told assembly members that campaigns suggesting risks associated with the MMR vaccine by “elements” of the media were a factor in the current outbreak.

The Welsh government has a target to ensure 95% of children receive both doses of the MMR vaccine. Some 94.3% have received the first dose by the age of two, but only 89.9% have received the second dose by the age of five.

Jones told AMs: “I believe that the publicity given over the past few weeks, although we would not have wished it to be this way, will help us reach those targets.”

Welsh health minister Mark Drakeford rejected complaints that the Welsh government was “behind the curve” in dealing with the measles outbreak in Swansea.

Officials decided to focus on vaccination in schools when the outbreak occurred last November, he said, but admitted that this was not successful in stemming the rise in cases.

“It was only in the post-Christmas period, as media reports increased, that greater awareness and parental action began to pick up,” he said.

“I don’t think there is any sense that either the Welsh NHS or the government have been behind the curve in responding to the outbreak.”