Cases of measles in England are currently at their highest recorded levels since 1994, with the total number of confirmed measles cases so far in 2013 up 64% on the same period last year.
However the number of monthly cases declined in May, after the launch of the government's MMR catch-up campaign. 10-14 year olds continue to be the age group most affected.
Highly infectious & unpleasant disease
Dr Mary Ramsay, Head of Immunisation at Public Health England said: "Measles is a highly infectious and unpleasant disease that can lead to very serious complications.
Children who have not had the MMR vaccine are at high risk of catching the disease.
"Thanks to the hard work of local health teams we are making good progress towards the 95 percent target, but there still remains a large number of 10-16 year olds, together with many younger children and adults who are under-vaccinated. The programme will continue until we reach as many children as possible in the age groups most affected."
Preliminary figures released today [11 July] by PHE estimate that around 56,000 previously unvaccinated 10-16 year olds in England have received a first dose of vaccine in the catch-up programme, and around the same number of partially vaccinated children have also received an extra dose of MMR.
Around 120,000 extra 10-16 year olds need to have their first MMR doses to reach 95 per cent uptake of the first dose.
School-based campaign 'actively considered'
Ninety-five per cent of GP practices have ordered extra vaccine and more than 200,000 extra doses of MMR vaccine have been delivered. To ensure as many children are vaccinated as possible, the need for a school based campaign is being "actively considered".
Professor David Salisbury, Director of Immunisation at the Department of Health, added: “The best way to beat measles is to protect people before measles catches them.
"It's encouraging that GPs have taken up the challenge wholeheartedly but we now need to make sure that all childre