British commentary: ’Low’ risk of human BF strain

The likelihood of the bird flu virus mutating into a form that can be transferred from human to human is "very low", the Government's top scientific adviser said.

Sir David King acknowledged that such a mutation could trigger a global pandemic, but said any suggestion that this was inevitable was "totally misleading".

He said: "The pandemic flu that we are now talking about would be in the human population. It is not in the human population at the moment. So yes the Government is preparing for that possibility, but I would say it's a very low possibility. I don't believe it is inevitable."

And he added: "As time progresses we have got a virus in the bird population that has gone on since '96, and in Asia particularly there has been a lot of contact between human beings and the birds that have got that virus.

"We still haven't seen the development of a human virus from that."

Sir David, challenged on ITV1's Jonathan Dimbleby show to say whether bird flu was in Britain, replied: "No."

He said it was "absolutely not" present among poultry, adding that he was "fairly optimistic" about its absence from the wild bird population.

He emphasised that to date only one dead bird had been washed ashore with H5N1 - and this may have come from an area of Europe that had previously been infected.

"The one swan doesn't mean it has arrived here. We need to see more evidence of spread before we can say that it has arrived in the UK," he said.

Sir David also warned that farmers would not be compensated if their birds became diseased - only if they were forced by the Government to cull them.