A national bird flu "prevention zone" has been declared to prevent the spread of the disease which ravaged East Anglia's poultry industry last winter.

Chief vets introduced the measures after avian influenza cases were found in captive and wild birds in Worcestershire, Warwickshire, Wales and Scotland.

This makes it a legal requirement for all bird keepers across the country to follow strict biosecurity measures to help protect their flocks.

Norfolk poultry farmers hope the restrictions could avoid a repeat of the outbreaks last December, which prompted culls of thousands of turkeys and ducks at several of the county's farms in the run-up to Christmas.

And they said it was vital that hobby farmers and back-yard bird keepers also stepped up their efforts to prevent outbreaks this year.

Mark Gorton is a director of Traditional Norfolk Poultry at Shropham, near Attleborough, and a member of the National Poultry Board.

He said: "As a poultry farmer, we always operate on the highest biodiversity anyway, so we won't have to do anything different apart from restricting more movement on our farms.

"But it makes people sit up and think about the need to review what we are doing and making sure everyone is complying with the standards that we set.

"Really the key to this is for hobby farmers and backyard farmers to know that it is really important to step up their biodiversity, no matter how many birds they have got."

The The Avian Influenza Prevention Zone (AIPZ) requires keepers with more than 500 birds to restrict access for non-essential people on their sites, workers will need to change clothing and footwear before entering bird enclosures and site vehicles will need to be cleaned and disinfected regularly to limit the risk of the disease spreading.

Backyard owners with smaller numbers of poultry including chickens, ducks and geese must also take steps to limit the risk of the disease spreading to their animals.

Avian influenza circulates naturally in wild birds, and when they migrate from mainland Europe over the winter they can spread the disease to poultry and other captive birds.

UK food and health agencies advise that the risk to public health from the virus is very low and that avian influenzas pose a very low food safety risk for consumers. Properly cooked poultry and poultry products, including eggs, are safe to eat.

The AIPZ now in force does not currently include a requirement to house birds, but it means all keepers across the country must:

  • Keep domestic ducks and geese separate from other poultry
  • Ensure the areas where birds are kept are unattractive to wild birds, for example by netting ponds and removing wild bird food sources
  • Feed and water their birds in enclosed areas to discourage wild birds
  • Minimise movement into and out of bird enclosures
  • Cleanse and disinfect footwear and keep areas where birds live clean and tidy
  • Reduce any existing contamination by cleansing and disinfecting concrete areas, and fencing off wet or boggy areas
  • Keep free ranging birds within fenced areas, and ponds, watercourses and permanent standing water must be fenced off (except in specific circumstances, for example zoo birds)

Bird flu is a notifiable animal disease. Poultry keepers and members of the public should report dead wild birds to Defra’s helpline on 03459 33 55 77 (option 7) and keepers should report suspicion of disease to APHA on 03000 200 301.