Stocks of last year's swine flu jab will be used to plug shortages in this year's vaccination programme as the death toll from the virus continues to rise.
The Government insisted there should still be enough seasonal flu vaccine for at-risk patients in England but a "mismatch" had occurred, with some regions having too much vaccine and others a shortage.
It came as figures showed 11 more people have died from flu across the UK, taking the number of deaths since the start of October to 50.
Angry patients wanting to be vaccinated have reported being turned away from GP surgeries while some doctors say they have run out.
But GPs, who order the vaccine based on estimates from previous years, are adamant they have not under-ordered.
Professor Dame Sally Davies, the interim chief medical officer for England, said leftover stocks of last year's swine flu vaccine would be made available to 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.
Prof Davies said: "We are hearing some stories of the (seasonal flu) vaccine being in one place and the patient being somewhere else.
"The message to the public is if they need the vaccine because they are in an at-risk group, they should come forward because we have it in the system."
The swine flu vaccine has a shelf life until the end of 2011. 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.
