Reports of positive bird flu infection in wild swans have been reported by Germany and Austria. In response to the H5N1 virus detection, the German government has ordered that all domestic poultry be moved indoors.
Four other European nations have reported outbreaks this week and the disease now appears unstoppable, at least among wild birds.
The latest suspected infections were in four dead swans on the island of Ruegen, off Germany's Baltic Sea coast. Preliminary tests showed that two of them might have the deadly H5N1 strain of the virus, the government said. Final laboratory results are expected Thursday.
The lethal strain of avian influenza has killed birds in more than 20 countries worldwide and infected at least 166 people, killing 91. There are fears that the virus may mutate and cause a human epidemic.