An avian flu “prevention zone” has been declared across Great Britain as the country continues to battle a “devastating” outbreak of the disease.
Officials announced it will now be a legal requirement for all bird keepers to follow strict measures to protect flocks from bird flu, including keeping free range birds in fenced areas and stringent biosecurity for staff on farms.
The move by the chief veterinary officers of England, Wales and Scotland comes following an increase in the number of cases of avian flu being detected in wild birds and commercial premises in recent weeks.
Officials warned the disease had “over-summered” in wild birds for the first time and the new winter outbreak was starting earlier than in previous years.
The UK has faced its largest ever outbreak of the disease in the past year with 190 cases confirmed across the country since late October 2021 – 30 of which were confirmed since the beginning of this month.
There are currently 47 cases in the UK, 43 of which are in England, two in Scotland and one each in Wales and Northern Ireland.
The situation is particularly severe in East Anglia where commercial and small-scale bird keepers are being hit, and mandatory housing measures for all poultry and captive birds in Norfolk, Suffolk and parts of Essex were introduced earlier in October.
The disease has also ripped through breeding colonies of seabirds, killing thousands in some sites and affecting threatened species from puffins to hen harriers.
UK chief veterinary officer Dr Christine Middlemiss said the unprecedented flu outbreak had hit since October last year, not just in the UK, but across Europe and in North America.
“It’s been devastating for bird keepers, whether you’re a backyard flock owner or a commercial farmer, whether you have conserved birds like the Wildfowl and Wetland Trust or whoever you are,” she said.
But she said that despite the culling of nearly 3.5 million birds in total, food supplies should not be significantly affected. The UK produces nearly a billion birds a year for eating as meat and for Christmas produces nine to 10 million turkeys.
“Whilst it’s devastating for those particular companies affected, in the overall food supply at the moment we don’t believe it’s going to have a significant impact.”
She said the outbreak was due to migratory birds arriving last October with a very infectious strain of highly pathogenic H5N1 bird flu, which caused massive infections over the last winter.
“For the first time ever we’ve seen the virus over-summer with us … in our native wild bird population and as they started to move around going into this colder weather now, we’re seeing new infections being created.”
Dr Andy Paterson, head of the Animal and Plant Health Agency (APHA) national emergency epidemiology group, said the data showed that: “Already we’re at a point that we were at six weeks later last year, so the outbreak is starting much much earlier this year”.
He said extreme weather such as, Storm Arwen and other events which battered the UK over the past winter, disrupted patterns of where wild birds were and also damaged buildings which could allow diseased wild birds to come into contact with poultry flocks.
And the UK has a large proportion of free-range poultry, making it more likely flocks would come into contact with wild birds.
But he added the risk of wild birds picking up the disease from commercial flocks was “very low”.
Professor Paul Digard, chair of virology at the Roslin Institute, The University of Edinburgh and member of the FluMap consortium, a government-backed project to fill in knowledge gaps in the disease, said it was not a major danger to people.
When the virus appeared in 1997, it was able to infect and cause severe disease in humans, but it appears to have become less infectious for people over the years, he said.
He added: “We have to keep an eye on it because it could change back the other way. But right now, I don’t think this is a major danger to people.”
Under the prevention zone rules, producers with more than 500 birds must restrict access for non-essential people on their sites, staff must change clothing and footwear before entering enclosures and vehicles will need regular cleaning and disinfecting.
Backyard owners of smaller numbers of chickens, ducks and geese must also take steps to limit the risk of the disease spreading to their flocks, they are being warned.
The prevention zone in force across Great Britain does not include a nationwide requirement to keep birds inside, but officials said that was being kept under constant review.
They also said the risk to public health from the virus was very low and properly cooked poultry and eggs are safe to eat.