There were an estimated 100,000 new cases of swine flu last week, the Health Protection Agency has said.
This is around double the number in the previous week, when 55,000 people were estimated to be newly-diagnosed with swine flu in England.
Most people with the virus in hospital in England are aged 16 to 64, with 435 cases, followed by the under-fives, with 169 cases.
Among those aged over 65, 149 people are in hospital and there are 87 cases among young people aged five to 15. Tower Hamlets in east London continues to be the primary care trust with the highest number of GP consultations for people with flu-like illness.
It is seeing 792 consultations per 100,000 people, followed by Islington in north London with 488 consultations per 100,000. Other badly affected parts of England include Greenwich, south east London, Leicester, and Telford and Wrekin.
The figures come as the National Flu Pandemic Service for England website crashed within minutes of going live due to the volume of people trying to access it. There are now 840 people in hospital with the virus, of which 63 are in intensive care.
A team working for the Government is now investigating deaths linked to the virus to see how much of a contributory factor swine flu is.
The Government's Chief Medical Officer, Sir Liam Donaldson said there were 26 deaths in England which were now provisionally validated, the same figure as last week.
But Sir Liam would not be drawn on how many of those deaths were new and how many deaths had been discounted in the new calculations.
"Some have gone out and some have come in," he said. "We are down to the sorts of numbers where it might be possible to identify individuals."
A number of the 26 deaths have been fully investigated but Sir Liam would not give the figure for reasons of patient confidentiality.
Of these, 67% had severe conditions such as leukaemia, 11% had moderate conditions such as insulin dependant diabetes, and 6% had mild conditions such as high blood pressure controlled by tablets.
A total of 16% of patients had no medical conditions and were not taking any medication.
Sir Liam said: "The bad thing would be if 100% of the deaths were healthy people.
"The vast majority of people, even with an underlying condition, will get the flu and recover well."
