So far the H5N8 virus has only affected wild ducks and herons, but the fear is it could spread to farmed chickens in Switzerland. Suspected cases of the virus were discovered at a poultry farm in Austria on Wednesday.
As a result, Switzerland, Austria and Germany are working together on prevention measures, including establishing a one kilometre perimeter around Lake Constance within which poultry on farms will not be allowed outside.
Switzerland’s federal food safety office (BLV) is also monitoring the lakes of Zurich, Biel/Bienne, Murten, Geneva, Neuchâtel and several canals, it said in a statement, however as yet it appears no wild birds in those areas have been affected.
The highly contagious H5N8 virus is transmitted by birds on migration routes south for the winter.
There is no evidence the virus can be passed to humans, however the BLV is advising people not to touch dead birds if they find them, and to tell the police.
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 people living nearby.