The two chickens were contaminated in the Noah's Ark animal pound in the southern Austrian city of Graz, where an injured swan infected with bird flu had been housed, Ministry of Health spokeswoman Daniela Retzek was quoted as saying. Hans Seitinger, agriculture official for the Steiermark region, told reporters that three ducks from Noah's Ark had also tested positive for H5N1.
Until now, H5N1 has been detected in wild birds that have migrated from the East to Europe.
The Austrian cases are considered especially alarming to the EU's poultry industry, so far untouched by the epidemic, and to health officials worried about human infection.
The nearest outbreaks on chicken farms have been in Romania and Ukraine, where the first cases were reported in early December last year.
Despite massive efforts to halt the disease's spread following outbreaks among migratory water fowl in a dozen European countries, new H5N1 cases are materializing every day across the continent. Despite early optimism, health and government officials are now admitting that quick containment is highly improbable.
"We will have to live with the virus for the foreseeable future," Germany's Agriculture Minister Horst Seehofer was quoted as saying today.
In Asia, where the H5N1 strain has killed some 100 people since 1997, the disease is thought to have spread from wild birds to domestic fowl, and then to humans working with infected chickens.