Ministers say the threat of swine flu remains serious
The first genetic code of swine flu from European samples has been unravelled by UK researchers.
The Health Protection Agency has also announced it has now shared isolates of the UK virus with scientists working on a vaccine against the strain.
It will enable researchers to compare the virus affecting humans in Europe with that in Mexico and the US and look at the immune reaction it causes.
Health secretary Alan Johnson said the work was a "significant step".
Researchers at the US Centers for Disease Control and Prevention had already made genetic information on the swine flu virus publicly available to scientists around the world.
But a team at the National Institute for Biological Standards and Control (NIBSC) have been specifically working on getting the full genetic fingerprint of the virus that has infected Europeans.
They will also share the information globally which will help scientists better understand how the virus behaves as it infects people.
And because viruses have the potential to evolve and change their behaviour as they spread, researchers are also keen to keep an eye on any changes that might occur as more people become infected.
Receipt of the first "pure" isolate of the UK virus from the HPA Centre for Infections is key for scientists and those in industry working on developing a vaccine.
In order to produce a vaccine and understand what sort of threat the virus may pose, researchers pin down the characteristics of the virus and the body's response to infection.
Professor Maria Zambon, director of the HPA Centre for Infections, said they were learning more and more every day.
"The pure sample of virus that we have isolated, together with its genetic fingerprint, will be important resources as scientific organisations join forces on the development of an effective vaccine.
"The rapid assessment of this virus will ultimately help us to make future decisions regarding the health implications of swine flu. "
Visiting the NIBSC, Alan Johnson said: "The speed with which vaccine prototypes can be created to combat potential pandemics is testimony to the dedication and world-class expertise of Health Protection Agency researchers.
"We have been preparing for the possibility of a pandemic for some time.
"We now look to the vaccine industry to produce the required quantities of vaccine as quickly as possible."