BRITAIN has stepped up its defences against the deadly strain of avian flu and is to increase surveillance at the most likely disease hotspots.

As thousands of wild birds return to these shores after spending the summer in the Arctic or in the Russian tundra, vets and ornithologists are on the alert for a possible outbreak of the H5N1 strain and other virulent forms of bird flu.

The areas deemed most at risk of triggering an outbreak are beaches, estuaries and other wetlands where gulls, geese, swans, ducks and waders gather in large numbers and which are near poultry farms.

Debby Reynolds, the Chief Veterinary Officer, has ordered intensive sampling of birds in priority areas, including the East of England coast, Morecambe Bay and the Solway Firth in the North West, the eastern coast of Scotland and the South Coast.

Teams of wildlife experts are being enlisted for the testing programme. Live birds will be tested and then released, and dead birds found in hotspots and birds shot for sport or pest control will also be examined.

Dr Reynolds said that the likelihood of finding a dead wild bird that had avian flu was very small. But she added: “We are doing most work in areas where there is a greater likelihood of finding the virus, but we will continue to be vigilant in checking for avian influenza across the country.”

The lethal flu virus was found in Britain last year in an imported parrot and in April a dead swan was identified with the virus at Cellardyke in Scotland. A low pathogenic strain of the flu also hit three poultry farms in Norfolk in April.