A British firm has developed a bird flu vaccine which could be easily mass produced, officials say.
More than 50 people have died from bird flu in south east Asia
PowerMed's vaccine is further away from the market than others, but as it is a DNA-based, it may be easier to produce than traditional egg-grown flu shots.
The firm said 1.2kg of the vaccine, which is expected to enter clinical trials next year, would be enough to vaccinate the US population twice over.
More than 50 people have died from bird flu in south east Asia.
At present H5N1 flu strain poses only a limited threat to humans as it cannot be easily spread from person to person.
But experts fear the strain will eventually mutate to acquire this ability, causing a flu pandemic, which could kill as many as 50,000 people in the UK.
PowerMed chief executive Dr Clive Dix said he believed enough of the vaccine could be produced within three months to vaccinate everybody.
He also said one advantage was that it could be easily adapted if the strain mutated - something experts believe is likely if a pandemic arises.
And he added: "No other vaccine technology offers this speed of response.
"In the event of a pandemic, most deaths and illness will occur in the first six months of an outbreak.
"We believe that our technology offers the best potential to save lives and minimise the economic impact of a flu pandemic."
PowerMed's vaccine is produced by cloning a gene from the current bird flu strain and slotting it into an existing DNA backbone vaccine.
Unlike many other vaccines it would not need to be kept refrigerated and does not need to be produced in as secure an environment as ones grown in chicken eggs as the risk of contamination through a live virus is reduced.
John Oxford, professor of virology at Queen Mary's School of Medicine, said the DNA-based vaccine was likely to play an important role in combating a flu pandemic.
"They have advantages of speed over some of the other vaccines, and also potentially in the way the immune system reacts to it.
"The cupboard is pretty bare at the moment so it is important these companies develop the vaccines."
Several countries across the world, including the UK, have already said they will stockpile doses of vaccines to fight a flu outbreak.