UK environment agency Defra is awaiting test results on poultry suspected to have caught the H7 bird flu virus after 35,000 chickens were slaughtered at a farm in Norfolk.

Preliminary results show that the birds were probably infected with the H7 strain of avian influenza rather than the feared H5N1 strain, with confirmatory tests in progress.  

A Defra spokesperson told just-food that further action surrounding the farm, near Dereham, would be subject to the virus’ pathogenicity.

“We haven’t got the strain of the variety yet,” the spokesperson said. “We are working on it as fast as we can.”

When asked whether migrating birds spread the suspect strain, just-food was told it was too early to say either way.

Defra added that the strain was likely to have been spread in the farm through bird faeces and the respiratory tract, but further measures on surrounding rural areas would depend on the pathogenicity of the virus.

Following a 2003 outbreak of the H7N7 strain in the Netherlands, 30m birds were slaughtered.