The catch-up campaign is aimed at 10-to-14-year-olds who as babies either had only the first of the two shots of the combined measles, mumps and rubella jab, or neither. It is aimed at vaccinating nearly 1m children as they get older, mix more and are more likely to come into contact with the disease. Measles has swept through Swansea in south Wales.

Immunisation rates have dropped as low as 70% in parts of London and south-west England – when 95% is necessary to prevent measles outbreaks. Unvaccinated children are at risk of the measles virus, which is one of the most infectious in the world.

Public Health England said there were 587 confirmed cases of measles in England in the first three months of this year, with the greatest number in the 10-to-14-year age group. That is three times more than the same quarter of 2012, the year with the highest number of cases (1,902) since the MMR booster was introduced in 1996.

At the campaign launch Professor David Salisbury, director of immunisation at the Department of Health, said: "The situation in Swansea, I believe, is a wake-up call for parents who, for whatever reason, quite a few years ago chose not to vaccinate their children and for whom vaccinations are these days not things they think about very much. But what is happening in Swansea could happen anywhere in England.