There have been an estimated 100,000 new cases of swine flu reported in England since last week and 840 patients are in hospital with the virus, 63 of them in intensive care, the Department of Health said.
This means the number of people consulting their GP because they think they have swine flu has almost doubled in one week, up from 55,000.
Of the 840 in hospital, 435 are are aged 16 to 64, 169 are under-fives, 149 are over 65, and 87 are 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 Government's chief medical officer for England, Sir Liam Donaldson, said a number of deaths had been fully investigated. Of these, 67 per cent had severe conditions such as leukaemia, 11 per cent had moderate conditions such as insulin dependant diabetes, and 6 per cent had mild conditions such as high blood pressure controlled by tablets. A total of 16 per cent of patients had no medical conditions and were not taking any medication.
Sir Liam said: "The bad thing would be if 100 per cent of the deaths were healthy people. The vast majority of people, even with an underlying condition, will get the flu and recover well."
He added: "The highest hospitalisation rate is for the under fives. Under fives remain the most likely to be hospitalised and the proportion being hospitalised has gone up a bit in the last week."
The new data comes as a telephone service for victims of swine flu is launched in England - capable of answering more than one million calls a week ( 0800 1 513 100 or, for Textphone, 0800 1 513 200 ).
The Government's National Flu Pandemic Service for England is being staffed by more than 1,500 call centre staff, with the option of recruiting 500 more. The initial 1,500 will be capable of more than 200,000 calls a day - or more than one million calls a week.
The phone line is accompanied by an internet service ( www.direct.gov.uk/pandemicflu ) where people answer a questionnaire to receive a diagnosis of swine flu. But the service was overloaded within minutes of going live under the weight of queries.
A DoH spokesman said the site was receiving 9.3 million hits per hour but insisted the site had not crashed. Also, BT was quadrupling the capacity to access the site.
People will supply their name, address and date of birth either online or to a call centre member of staff before receiving a code.
This code can then be given to a "flu friend" who will collect the antiviral Tamiflu from a collection point on the patient's behalf, using a form of identification from the patient.
More serious cases such as pregnant women, people with health conditions and very young children will still be referred to GPs.
The free phone number will be up and running for 15 hours a day initially but it could become a 24-hour service if required.
Details of the website address and helpline number will be released later today.
Chief Medical Officer Sir Liam Donaldson will also announce the latest number of deaths linked to the virus, with the death toll currently standing at 31.
A jump is also expected in the number of people contacting their GP as well as a rise in the numbers being hospitalised for swine flu.
The new phone service goes live as a poll of health workers reveals that only around four out of 10 believed their organisation was managing to cope with the extra flow of patients.
In a survey of almost 1,500 NHS managers, nurses and doctors - carried out by the Health Service Journal and the Nursing Times - just 37 per cent of clinicians, including doctors, nurses and midwives, agreed or strongly agreed with the statement that their organisation was coping well.
Another 30 per cent neither agreed or disagreed while 13 per cent disagreed and 5 per cent strongly disagreed.
However, many doctors and nurses said the Government had provided useful advice to help them cope with the pandemic and most would not stay away from work if other staff became ill.
Staff were also asked to rate their confidence on a series of questions on a scale of one to 10, where one was not at all confident and 10 was extremely confident.
In answer to the question "How confident are you that the NHS as a whole is well prepared to deal with the greater demand on services expected later in the outbreak?", the average score was five.
Asked "How confident are you that there will be adequate supplies of swine flu vaccinations to protect the population?", the average score was 4.8.
And in response to "How confident are you that there will be a practicable logistical plan to vaccinate all those who need immunisation?", the average score was 4.6.
Yesterday the Prime Minister said the Government was making an "enormous effort" to tackle the pandemic.
Gordon Brown insisted "robust plans" were in place to fight it and measures were being taken in a "calm and organised and ordered way".
The UK pharmaceutical giant GSK also said yesterday that first batches of its vaccine would not be available until September, with further shipments in 2009 and 2010.
The Government has ordered up to 132 million doses of the vaccine from GSK and another drug company, Baxter.
Baxter is expected to ship its first batches at the end of this month or in early August.
More than 700 people worldwide are known to have died after getting swine flu which the World Health Organisation says is spreading faster than any previous flu pandemic.
Speaking at Paddington station in London today about the new flu helpline, Mr Brown said Britain was the first country to introduce such a service.
He added that it would reduce GPs' workloads and provide the advice that people needed.
Mr Brown added that people should heed the advice they were given so they could be treated as quickly as possible.