The strain of H7 bird flu found in chickens near Banbury, Oxfordshire, is “highly pathogenic”, Britain's Department for Environment, Food and Rural Affairs (Defra) said today.
All birds on the infected farm are to be slaughtered as a precautionary measure after the case of avian flu was confirmed by new chief veterinary officer Nigel Gibbens yesterday.
Defra said a temporary control zone with a three kilometre inner zone and a ten kilometre outer zone has been established around the infected premises.
In the inner zone, poultry must be housed and kept isolated from wild birds, and across the whole zone movement of birds and bird gatherings are banned.
Defra is also considering whether any wider measures might be needed.
The Health Protection Agency said the H7 strain of avian flu was largely a disease of birds and did not transmit easily to humans. The risk to human health posed from the strain is low, it said.
The Food Standards Agency said the case of bird flu "poses no safety implications for the human food chain".
While the risk of H7 to humans is low, the local health protection unit will be tracking down everyone who had contact with the infected birds and offering preventative medicine where appropriate, Defra said.
This is the fourth case of the H7 strain in the UK, with three outbreaks of the "low pathogenic" or mild version of the virus in Norfolk, North Wales and Merseyside since May 2006.
A number of people were treated for flu symptoms or conjunctivitis in Conwy, North Wales, after contracting the disease from poultry in May 2007.
Only the H7 and H5 strains can become "highly pathogenic" or deadly to birds, and H5N1 is the strain which has caused a number of human deaths worldwide.
H5N1 has been found in poultry and wild birds in the UK on a number of occasions since October 2005, when it was discovered in a bird in quarantine in Essex.
Most recently the highly pathogenic version of the disease was found in wild swans in Dorset.