Public confidence in the triple MMR vaccine dipped following initial research
The number of cases of measles in young people has reached its highest level in over a decade.
The Health Protection Agency says in most cases it could have been prevented if children had been given the MMR vaccine.
Measles cases in England and Wales rose by more than 70 percent in 2008 from the previous year.
Confirmed cases increased from 990 in 2007 to 1,348 last year according to Health Protection Agency.
These are the highest figures since the virus was first monitored in 1995.
"There are still many children out there who were not vaccinated as toddlers over the past decade and remain unprotected," Mary Ramsay, an immunisation expert at the agency, said in a statement.
"Unfortunately this means that measles, which is highly infectious, is spreading easily among these unvaccinated children."
Public confidence in the triple MMR - measles, mumps and rubella - vaccine dipped following research - since discredited - which raised the possibility that the jab may be linked to an increased risk of autism.
It has led to some parents opting to pay privately for single vaccines.
The latest data on the uptake of the MMR jab in England and Wales shows that 84.5% received the first dose by their second birthday.
The number of pre-school children receiving both doses of MMR by their fifth birthday is 77.9%.
But the World Health Organisation says 95% of children need to be vaccinated to ensure herd immunity.
"The year-on-year increase of measles across England and Wales is very worrying," said Dr Ramsay.
"Measles should not be taken lightly as you can never tell who will go on to develop the more serious complications of pneumonia and encephalitis.
"This is why it's incredibly important to remember that measles isn't a 'harmless' childhood disease and that it is never too late to get your child immunised with the MMR vaccine."
David Salisbury, head of immunisation at the Department of Health, said that despite the rise, the number of cases was still relatively low compared to before the measles and MMR vaccines were introduced.
But he added: "We shouldn't be having 1,300 cases. We should be having hopefully no cases because measles is a disease that you simply would not wish your children to have.
"You don't take risks with your children's lives and children's health."
He said measles killed one child in Britain last year.
Dr Salisbury also confirmed 10% would develop short-term complications after contracting the disease, while one percent would suffer longer-term difficulties.