Eleven more people have died from flu across the UK, taking the total to 50, the Health Protection Agency said yesterday.
Of these, 45 died from swine flu and five with another strain, flu type B.
The deaths are mostly among children and young adults, with five cases in the under-fives and eight cases among those aged five to 14.
Another 33 cases involve people aged 15 to 64.
The figures come as some hospitals have been told to cancel operations to make way for the most seriously ill flu patients.
The NHS is preparing to expand the number of beds available for a highly specialised treatment, which is often seen as a last resort.
Extra corporeal membrane oxygenation (Ecmo) helps patients whose lungs or heart are not working normally and uses an artificial lung to oxygenate blood outside the body.
Earlier yesterday, further details emerged of people who have died from flu.
Among them is 32-year-old Sarah Applin, of Thurston, Suffolk, who died following swine flu complications two weeks after giving birth to a son. Mrs Applin died at West Suffolk Hospital in Bury St Edmunds on Tuesday.
Her parents, Jane and Barry Waterman, said: “Our daughter... sadly died ... of complications with pneumonia following treatment for swine flu. We would like to strongly urge any person on the at-risk register, especially pregnant women, to have the flu vaccination.”
Family members said Mrs Applin gave birth to son William by Caesarean section on December 22. Mrs Applin and her husband Richard also had a four-year-old daughter.
Another woman, 45-year-old Julie Roberts, a school attendance worker from Liverpool, died on Monday.
Mother-of-two Hilary Robinson, 37, from Ormskirk, Lancashire, died on Christmas Eve of complications understood to be connected to the illness.
Ms Robinson, a hairdresser, had gone to the walk-in centre at Ormskirk Hospital around midday on Christmas Eve. She was then taken to Southport Hospital where she later died.
Professor Dame Sally Davies, the interim chief medical officer for England, confirmed the Government would be releasing leftover stocks of last year’s swine flu vaccine for those GP surgeries which have run out of seasonal flu vaccine.
Some 12.7 million doses of GlaxoSmithKline’s Pandemrix swine flu vaccine are still held centrally by the Government.
The swine flu vaccine has a shelf life until the end of this year.
Although it will not offer protection against all strains of flu circulating this year, it will protect against the dominant strain, which is swine flu.
The NHS is recommending that people who had the swine flu vaccine last year still come forward for this year’s seasonal flu vaccine if they are in an at-risk group, to ensure they are protected against all strains.
Dr Tarit Mukhopadhyay, from University College London, said more seasonal flu vaccine could not be produced because there is a time lag of six months.
“The flu vaccine is still primarily produced in chicken eggs, which means there is a significant lag time to prepare the vaccine.
“This year, manufacturers folded the H1N1 (swine flu) strain into the seasonal vaccine in order to deal with the predictable increase in seasonal swine flu cases.
“It would seem, however, that errors were made in not ordering enough vaccine from the manufacturers, correctly identifying the ‘at risk’ groups and deciding to drop the flu jab ad campaign.”
Professor David Salisbury, director of immunisation at the Department of Health, said GPs order stocks of seasonal flu vaccine every year based on estimates of how many people will come forward for the jab.
Prof. Salisbury insisted the swine flu jab would offer good protection.