Scientists and the European Union's political chiefs are trying to ease public concern after the H5N1 virus was confirmed in Romania at the weekend, only two days after its presence was identified in Turkey.

EU foreign ministers will discuss the outbreak at emergency talks in Luxembourg on Tuesday, while the bird flu scare will dominate the agenda of a meeting of health ministers later in the week.

On Wednesday, health commissioner Markos Kyprianou will present a pandemic simulation exercise aimed at testing the preparedness of the bloc's 25 members for such an outbreak. The scenario will be played out by year's end.

The World Health Organization immediately voiced concern at the Romanian outbreak and admitted that the risk of bird-to-human transfer had increased. "The presence of this virus in Romania worries us, because it proves that it is in the birds' environment, and that increases the possibility of transmission to humans," said a spokesman in Geneva.

But it has kept its pandemic alert at phase three -- the middle of its scale -- as "a virus new to humans is causing infections, but does not spread easily from one person to another."

Virus on the doorstep

The EU banned imports of birds and poultry products from Romania and Turkey last week after the presence of bird flu was confirmed. It was thought to have arrived via migratory birds from further east.

But on Saturday the scientists confirmed fears that the highly pathogenic Asian strain had been found in three ducks found dead in the Danube Delta, on Romania's Black Sea coast.

"The virus taken from (the village of) Ceamurlia de Jos is indeed the H5N1," Romanian farm minister Gheorghe Flutur said. "We are discussing what measures are needed to strengthen the protection zone around the source."

Some good news surfaced on Sunday, when he announced that a number of swans which had died in the delta did not have the virus, and Turkish officials ruled out a second possible case there.

Killer H5N1 strain heads to Europe from Asia

While avian influenza primarily affects birds, the H5N1 strain has killed more than 60 people in Southeast Asia since 2003 -- around half those who have contracted it. The big fear is that H5N1 may mutate, acquiring genes from the human flu virus that would make it highly infectious as well as lethal -- possibly killing millions worldwide as the influenza pandemic of 1918 did.

Citing such precedents, Britain's chief medical officer said on Sunday that bird flu would inevitably combine with a human variety and cause a pandemic that would kill around 50,000 people in his country alone.

"The significance of it isn't that there will be a pandemic of bird flu itself, the significance of it is that at some point, and we go by the lessons of history, the bird flu virus will combine with a human flu virus and then it will become easily transmissible," Liam Donaldson told BBC television. He noted that common winter flu kills more than 12,000 Britons each year.

Massive research activity offers hope

Countries from Germany to Vietnam to the United States are busy looking for a remedy. Hungary expects to know within two weeks whether human trials of its vaccine have been successful.

The European Commission, meanwhile, has urged member states to stockpile anti-viral drugs, and says people at risk should ensure they are vaccinated against regular flu.

EU veterinary experts have also demanded immediate action to prevent migratory birds which could carry the virus from coming into contact with poultry, including moving farmed birds indoors.

Public told not to panic

While they are keen not to spark panic, official calls for calm have not prevented a rush for anti-viral drugs and stocks in some countries are reported to be running short.

Fueling further concern, a study released Friday said researchers had identified a mutated form of H5N1 bird flu that is resistant to Tamiflu, the drug being stockpiled around the world to counter a feared pandemic.

European Commission head Jose Manuel Barroso said at the weekend that the EU was ready to take "more drastic and radical measures" if necessary, depending on how the situation evolves.