GPs across the UK could face a shortage of seasonal flu jabs for the winter campaign, even if manufacturers opt to add swine flu into the vaccine, rather than developing a new jab.
Currently, there is no vaccine available for influenza A(H1N1), but the move to influenza pandemic alert phase five is a clear signal from the WHO to governments and pharmaceutical companies to boost preparedness.
Last week, Dr Margaret Chan, director-general of the WHO, said that she had 'reached out to influenza vaccine manufacturers that can contribute to the production of a pandemic vaccine'.
The National Institute for Biological Standards and Control, part of the Health Protection Agency, is examining whether there is any cross protection between current and past H1N1 seasonal vaccines and the swine virus.
But Berkshire GP Dr George Kassianos, RCGP immunisation spokesman, warned that adding the swine flu strain to the production of the current flu jabs would still cause shortages.
'Seasonal flu jab production started back in February when they identified the strains, but this will have to be halted if we are to add in another strain.
'As it takes at least six months for flu jabs to be made and then tested, delays will be inevitable.'
Dr Nigel Higson, a Brighton GP and virologist, said that work to produce a swine flu vaccine could lead to a shortage of the hens' eggs needed for the production of seasonal flu jabs.
A spokeswoman for GSK, said: 'GSK is continuing to produce and maximise supply of its seasonal influenza vaccine for use in the Southern hemisphere, as it enters the winter season, and for the Northern hemisphere later this year.
'This remains a critical priority as seasonal flu infects 5 to 15 per cent of the global population and accounts for up to 500,000 deaths each year.
Eric Althoff, a spokesman for Novartis, said the impact on seasonal production would have to be evaluated if a switch to pandemic production were requested.
- 3,000-4,000 deaths a year in UK are attributable to seasonal flu.
- Flu jabs are recommended for those over 65 and at-risk groups.
- Flu jab uptake in eligible groups in England was 74 per cent for 2008/9.