Nearly a million free range ducks and geese in France are set to be inoculated against bird flu.
People have been banned from the Dombes wetlands of France
The vaccination programme began on Monday in the Landes region, on the Atlantic coast of south-west France.
France earlier confirmed that 15 swans in the south-east had been found to be carrying the potentially deadly H5N1 strain of bird flu.
Bosnia-Hercegovina is one of the latest countries to confirm the presence of H5N1 in wild swans.
Experts said tests carried out on the UK on two wild swans culled at a lake near the western town of Jajce did have the H5N1 virus.
Bosnia has now banned poultry imports from affected countries and ordered that birds be kept indoors.
The H5N1 virus, which causes bird flu, does not pose a large-scale threat to humans, as it cannot pass easily from one person to another.
Experts, however, fear the virus could mutate to gain this ability, and in its new form trigger a flu pandemic, potentially putting millions of human lives at risk.
Meanwhile, in Paris veterinary experts from more than 50 countries are meeting to discuss ways to combat the virus.
The two-day meeting is taking place at the World Organisation for Animal Health, which alongside the Rome-based Food and Agriculture Organisation is co-ordinating the international veterinary response to H5N1.
Among the participants will be countries like Iran, Kuwait and Azerbaijan, which fear that they could soon be hit by the virus.
The BBC's Hugh Schofield in Paris says they badly need to hear the latest thinking on detection, surveillance measures, slaughter and vaccination.
On the Atlantic coast the French authorities have authorisation from the European Union to vaccinate nearly a million birds they say cannot practically be moved indoors.
The geese and ducks - on nearly 150 farms - are destined for production of foie gras.
The operation, which only involves young birds, will take up to six weeks.
The Landes region has decided to carry out a vaccination programme because it is not considered practical to keep the birds indoors.
The 15 dead swans were found in the same Ain district where a turkey farm was on Saturday announced to be contaminated with bird flu.
About 400 of the 11,000 birds on the farm had died from the virus - the others were then slaughtered.
It was the first outbreak of bird flu in commercial poultry in the European Union.
The whole of the wetland area known as the Dombes has now been put off-limits in an attempt to keep people away from large flocks of wild birds.
Hong Kong has followed Japan in banning poultry imports from France.
In other countries, like Nigeria and India, ministers have urged people to continue eating poultry products as long as they are well-cooked, fearing the collapse of important poultry industries.
In Switzerland, the authorities are awaiting the results of tests on samples of what may be its first case of H5N1 bird flu.
A duck was found to be a carrier of the less specific H5 virus, but samples have been sent to the UK for definitive tests.
In Romania, preliminary tests indicated that a man suspected of having contracted bird flu does not have the disease, doctors said.