Greece yesterday confirmed its first case of bird flu, as the disease that has plagued south-east Asia continued its rapid spread westward. It is the first country in the European Union to report apparent infection, although cases are being tackled in Turkey and Romania.

The Greek agriculture minister, Evangelos Basiakos, reported the case on a turkey farm on the Aegean Sea island of Oinouses, near the coast of Turkey. The European commission said last night it was preparing to ban the movement of live birds and poultry meat from the region, which also includes the nearby resort island of Chios.

Authorities in Romania were yesterday monitoring poultry in six more villages in the Danube delta, amid fears that quarantine restrictions on villages already suspected of harbouring the disease may have come too late. Bulgaria and Croatia are also testing birds, although as there is no evidence yet of infection.

The developments came as Patricia Hewitt, the health secretary, told the Commons there was "no direct threat" to people in Britain. "This is a bird disease. There is no reason for people to stop eating poultry," she said, insisting that the government was ensuring that the country was as fully prepared as possible for any pandemic flu outbreak in humans.

Planning in this country is based mainly on an estimate that about 50,000 people might die in such a global pandemic, four times Britain's 12,000 flu-related deaths each winter. But the government recognises deaths might top 700,000.

The US health secretary, Mike Leavitt, speaking in Jakarta, Indonesia, warned yesterday that "no nation is adequately prepared for a pandemic avian flu", but most were improving. This week British scientists will travel to Asia to speak to experts in Vietnam, China and Hong Kong about the impact of avian flu there and see whether surveillance of flu in birds and humans can be improved.

The trip, by experts from the Medical Research Council, is sensitive as China was suspected of covering up the extent of the Sars crisis and there have been no reported human deaths from avian flu there. About 60 deaths have been reported elsewhere in south-east Asia.

Only 120 cases of bird flu in humans have so far been confirmed since 2003, suggesting that half of those who caught it from close proximity to birds have died. But it is unclear whether other people have caught it without displaying serious symptoms. So far the virus has not changed in a way that makes it easily transferable between people.

Sir John Skehel , director of the MRC's National Institute of Medical Research, said it was important to know whether other people had caught the flu from birds. "We would like to know precisely how the Chinese are responding to such a widespread infection of their chickens, how they are looking at their birds, how they are looking at their human beings for having potentially been infected. That information is not available at the moment."

Dr Alan Hay, director of the council's World Influenza Centre, said: "Influenza has always been regarded as a global disease and requires a global effort to combat it, if not conquer it." The MRC's chief executive, Colin Blakemore, said there were "understandable sensitivities in China" and it would be false to suggest it was the source of all the problems.

Romania has ordered the culling of 17,000 chickens in Ceamurlia de Jos, the worst-affected village, but regional veterinary experts said yesterday that a teacher had moved to a neighbouring hamlet, taking her hens with her, two weeks before they quarantined the area.

These hens had now been slaughtered and serum sent for testing. "If it comes back positive, we may have a problem," said Marian Avram, the head of the veterinary directorate in Tulcea.