More than 100,000 swine flu cases could be diagnosed every day by the end of next month, the Health Secretary has warned. Britain has moved past the stage of trying to contain the spread of the virus and into the “treatment phase”, Andy Burnham told the House of Commons.

Cases of the H1N1 virus were doubling each week in Britain and could reach six figures daily by the end of August if current trends continued, he added. Anyone with flu-like symptoms will be advised to stay at home and telephone their GP for advice. Doctors have warned that “several million” people could become ill as the flu season returns in autumn and winter.

Mr Burnham emphasised that most people who had become infected with the virus had developed only mild symptoms but widespread disruption to the economy is expected as people take days off work with flu.

A vaccine for the H1N1 strain, which has spread across the world, is understood to be at an advanced stage of development and could start becoming available as early as next month.

Now that the country is in the treatment phase, the policy of closing schools will be stopped and suspected cases of flu will be diagnosed by doctors assessing their symptoms rather than by a laboratory test. From now on, doctors will also use the drug Tamiflu (oseltamivir) more selectively, giving it only to people with symptoms rather than anyone who has come into contact with a swine flu victim.

If doctors believe that someone is suffering from swine flu he or she will be told to stay at home and will be sent a voucher that a friend or family member could take to a pharmacy or drug collection point to exchange for medication, Mr Burnham said. Doctors have been given the discretion not to prescribe the drug if, for example, they are inundated with calls. The move has been made to relieve the pressure on the health service and the Health Protection Agency, which has been managing the outbreak, but is effectively an acknowledgement that the virus can no longer be contained.

“We have reached the next stage in management of the disease,” Mr Burnham said. “The national focus will be on treating the increasing numbers affected by swine flu.”

The latest figures show that there are 7,447 laboratory-confirmed cases in the UK, with most being recorded in the West Midlands, London and Scotland. Three people, all with pre-existing health conditions, have died in Britain after testing positive for the H1N1 flu strain. Mr Burnham added that the 100,000 figure was “only a projection”, made by experts advising Cobra, the Government’s contingencies committee, on the basis of cases confirmed last week. “There are now on average several hundred new cases every day,” he said. “It could get better, or it could get worse. But scientists expect to see rapid rises.”

Some experts believe that antivirals should be given only to the most vulnerable as the virus is quite mild and overuse can lead to resistance. But Sir Liam Donaldson, the Chief Medical Officer for England, defended the Government’s “aggressive” approach to controlling the outbreak and said that Tamiflu would be offered to anyone with diagnosable symptoms.

Swabs would continue to be taken from a small number of patients to keep track of how the virus was evolving, such as whether it was becoming resistant to treatment, he said. The effects of the pandemic may be felt for many years to come, he added, leading to higher than average illness and death rates in winter flu seasons. Sir Liam said he could not estimate how many people might die, but that such predictions could be possible in the next few months.

“It is following a predictable path — it isn’t out of control, but flu viruses cannot be put back in their box once they are out,” he said. Asked if the projected figures were likely to mean there would be 40 deaths a day by the end of August, Sir Liam told Newsnight on BBC One: “We can’t be sure about the death rate nor can we be sure about the number of cases that will be occurring by the end of August but these are scientific projections. The numbers could be lower than this, they could be even higher. There are always excess deaths with any flu virus.”

The number's up

7,447 cases of H1N1 swine flu confirmed in Britain so far. Three people infected with the virus have died

100,000 new cases predicted each day by the end of August

35 per cent of the population may become ill at the peak of the pandemic

£800m cost of antiviral drugs stockpiled to treat 80 per cent of the population

£155m cost of contracts for vaccines for the pandemic flu strain over four years

12,000 deaths annually due to seasonal flu, likely to be far exceeded in a pandemic

Sources: Department of Health, Times database

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