Scientists at two Oxford centres are at the forefront of the fight to defend the world from a possible swine flu pandemic. At Oxford University’s Jenner Institute, where about 400 scientists work on human diseases, Dr Sarah Gilbert is upbeat about clinical trials now underway into a vaccine that would attack all strains of flu virus — including swine flu — with just one jab to last for life.

And at the university’s Department of Biochemistry, Prof Elspeth Garman is working on a drug to attack the structure of the virus.

Speaking from Cannes, in France, where she was attending the Influenza Vaccine for the World conference, Dr Gilbert told The Oxford Times: “By targeting the internal protein of the virus we hope to come up with a universal jab.

“Existing vaccines only target the surface proteins. But it is these proteins that constantly mutate, turning themselves into moving targets for researchers.”

Dr Gilbert’s vaccine targets the virus’s internal proteins — which do not change.

She added: “We will shortly test the vaccine for efficacy, giving the vaccine to 12 patients and not giving it to another 12. Now the development could be accelerated because of swine flu. We have been in discussion with pharmaceutical companies about this.”

And at the Department of Biochemistry, Prof Elspeth Garman told The Oxford Times that she planned to use the £260m Diamond Light Source at the Rutherford Appleton Laboratory, on the Harwell campus, to examine the N protein in the new H1N1 swine flu virus.

She explained that a vaccine produces an attenuated (or weakened) version of the harmful protein in order to encourage the human defence system to produce antibodies to fight it, whereas a drug (such as Tamiflu or Relenza) attacks the virus itself.

She said: “The existing drugs, Tamiflu and Relenza, lock the N protein in the infected cell and prevent it from spreading. Luckily, swine flu is apparently able to be contained by Tamiflu.”

She added that there were two vital tests for viruses: infectivity and pathogenicity. The first measures how easy it is to catch, and the second how deadly it is.

She said: “Bird Flu (or H5N1) has a killer rate of 63 per cent but is comparatively hard to catch. Swine flu (H1N1) is easier to catch, but apparently kills only six per cent.”

However, she warned that the flu pandemic of 1918-19, which killed up to 50 million people worldwide, only had a killer rate of between three and five per cent — so about one billion people must have caught it.

Dr Garman said no one yet knew why swine flu appeared to be more deadly in Mexico than in other parts of the world. She said: “It could have mutated downwards and become less deadly as it travelled. Or the recorded cases in Mexico could have been the tip of an iceberg, with many more unreported cases having been less bad. Or local conditions could have meant that the virus worked with another virus, causing a co-infection.”

Dr Garman explained that there are 16 different H proteins and 9 N proteins, making 144 combinations, that the flu virus might have.

The H part attaches itself to an infected cell like velcro and the N part cuts its way out — “like scissors”, in her words.

And it is the N part that interests her, because the disease can be contained by locking it into a cell, preventing its spread.

Some scientists believe they are in a race against time and that a pandemic on the scale of 1918 will one day occur again — even if it can be contained.

Dr Garman’s quest remains to find a fast diagnostic test for any strain of flu.

At the moment, tests takes two days, not five minutes. And existing drugs only work in the first 48 hours after symptoms have developed.

She added: “You could walk in and scrape your throat with a lollipop and it would turn bright green or bright red and the chemist could confirm whether or not you had flu.”