Austria had already ordered individual farms near Lake Constance, which borders Switzerland and Germany and where dead wild birds had been found, to keep poultry indoors, disinfect equipment more rigorously and avoid using open pools of water.
Such “protection zones” will now be extended to cover the whole country after new bird flu cases were confirmed further east, in Slovakia and the Czech Republic near their borders with Austria, the Health Ministry said.
Several European countries and Israel have found cases of the contagious H5N8 flu strain over the past two months and some have ordered poultry flocks be kept indoors to prevent the disease spreading. The strain can kill birds but has so far not been found to harm humans.
Tens of thousands of animals have been culled to try to prevent the virus from spreading.
These include birds on an Austrian poultry farm in the western province of Vorarlberg after a turkey tested positive for the flu virus in November.