VIENNA (Reuters) - A turkey on an Austrian poultry farm in the western province of Vorarlberg has tested positive for the H5N8 bird flu virus, and all birds on the farm will now be culled, the health ministry said on Friday.

Germany, Austria, Croatia and Switzerland have all reported outbreaks of the virulent strain of the disease affecting wild birds to the World Organisation for Animal Health (OIE).

The H5N8 virus has also been found in wild birds in Hungary, Poland, the Netherlands and Denmark, the French Agriculture Ministry said on Thursday.

Austria and Switzerland on Thursday took precautionary steps to prevent the spread of bird flu to domestic poultry after discovering cases of the disease in wild ducks around Lake Constance, in the latest in a series of cases across Europe.

No infected birds have been found near other Austrian and Swiss lakes and rivers so far.

Austria's health ministry said a protection zone with a radius of at least 3 kilometers (1.86 miles) and a surveillance zone with a radius of at least 10 kilometers around the infected holding will be created to keep migrating birds from transmitting the disease to farm poultry.

All poultry in the area will be examined by a legal veterinarian.

Germany has reported an outbreak of H5N8 in the northern state of Schleswig-Holstein, and Hungary's food safety authority said last week it had found traces of bird flu at a poultry farm in eastern Hungary and would destroy 9,000 turkeys to protect nearby populations.

The Dutch government said on Wednesday it had ordered farmers in the Netherlands to keep poultry flocks indoors.

(Reporting by Francois Murphy, Kirsti Knolle; Editing by Jason Neely and Hugh Lawson)