The Health Protection Agency (HPA) provisional figures show 665 cases were reported in the first three months of 2012, compared with 1,040 cases across the whole of 2011.
Cases are spread across all regions of England and have clustered in schools, universities and healthcare settings.
The increase in cases has recently spread to infants, who have the highest risk of severe complications and death.
The HPA has written to GPs to remind them of signs and symptoms of the infection, and to stress the importance of vaccination.
Dr Mary Ramsay, head of immunisation at the HPA, said: 'The agency is also encouraging GPs to report cases quickly and to make them aware of the HPA’s guidance to help reduce the spread of the infection.'
She added: 'Parents should ensure their children are up to date with their vaccinations so that they are protected at the earliest opportunity.'
Dr Ramsay urged patients to visit their GP if they develop symptoms.
Latest UK figures show 95.1% of infants under one year old had received their primary immunisation with the five-in-one vaccination DTaP/IPV/Hib, which protects against whooping cough. Uptake was 96.6% in those aged under two and 88.2% by age five.
Measles cases have also risen slightly since the beginning of 2012, the HPA said. A total of 251 cases were reported in January-March 2012 compared with 200 in the same period last year.
Dr Ramsay said: 'As we approach the time of year when many children are travelling on school trips and family holidays, we are again urging parents to protect their children against measles by ensuring they have been immunised with two doses of MMR.'
It follows an ongoing outbreak of measles in the Merseyside area.