A highly secure laboratory in North London is preparing to receive samples of the deadly swine flu virus from the US.
The World Influenza Centre at the National Institute for Medical Research will test the virus in a level four category containment lab – the most secure there is for this type of work.
It is housed in a specialist unit with airlocked doors and supercooled freezers for storage at -80 degrees celsius.
The viruses coming from the Centre for Disease Control in Atlanta are the latest mutations of the disease.
The preliminary analysis of the samples will take just a day or two, but attempts to find a vaccine using ferrets infected with the disease could take months.
The director of the World Influeza Centre, Dr Alan Hay, warned the swine flu epidemic could kill people in the UK and elsewhere in the US and Europe.