Dead swans in Germany and Austria have tested positive for the H5N1 bird flu, and Iran also confirmed an outbreak of the virus.
In Germany, swans found on the island of Rügen came up positive for H5N1 in preliminary tests, and will be taken to a British laboratory for further testing. Poultry within a two-mile radius of the swans will be tested for the disease, which has killed 91 people worldwide.
The Agriculture Minister Horst Seehofer ordered that all domestic birds be kept indoors from Friday.
Mr Seehofer had already ordered farmers to enclose poultry and other domestic birds in barns or cages with roofs from 20 February due to fears of bird flu after the discovery of H5N1 in swans in Italy and Greece.
In Austria, the Agency for Health and Food Safety confirmed that H5N1 was present in dead swans, and that it had also sent samples of the dead birds to the EU's reference laboratory in Britain.
The United Nations' Food and Agriculture Organisation has warned that the virus could spread further into Europe as migrating birds returned to the continent from Africa.
Samuel Jutzi, the director of the FAO's animal production and health division, said: "We need to be aware that there's a real risk for Europe when the birds migrate northwards this spring."
As the virus spread through Europe and authorities were on alert for dead birds, Slovenia confirmed six new cases of bird flu near the Austrian border yesterday.
The new cases were discovered after testing on five swans and a heron found frozen on farmland. On Sunday, the virus was found in a dead swan near the northern city of Maribor.
Hundreds of chickens and other birds had already been culled, as vets advised farmers to feed and water their poultry indoors to reduce any chance of them mixing with wild birds. People were also advised to avoid contact with birds.
Albania and Macedonia have banned imports of poultry from Greece, Italy, Bulgaria and Slovenia.
Albania and Macedonia have, so far, not detected any H5N1 cases. Albania was also buying protective clothing and stockpiling antiviral drugs.
Imports from other Asian and European countries with bird flu cases have been banned in Albania, and authorities urged people to avoid contact with dead birds. Hunting wild birds has been prohibited, and experts were checking lagoons for sick or dead birds.
Morocco has stepped up checks for avian flu. The virus was discovered in Nigeria last week, and Moroccan health experts fear it will be carried to northern Africa by birds flying to Europe.
L'Economiste, a French language newspaper in Morocco reported yesterday that several dozen wild birds had been found dead around lakes near Morocco's Middle Atlas mountains, and said officials were beginning checks to find out why.
"It's critical from this week onwards for Morocco. Birds have already begun to migrate back north," said Mohamed El Haouadfi, professor of avian pathology at Rabat's Hassan II Agronomy and Veterinary Institute.
Across Europe and into Africa, countries have reported drops in poultry sales.
The H5N1 virus has killed at least 91 people in Asia and Turkey since 2003, according to the World Health Organisation. Almost all of the deaths have involved contact with infected poultry, but experts fear the virus could mutate into a form that spreads easily among people, possibly starting a human flu pandemic.Reuse content