ENGLAND is still in the grip of its worst-ever bird flu outbreak, with more than 130 cases confirmed since October last year.

The Department for Environment, Food and Rural Affairs has imposed an Avian Influenza Prevention Zone in all of Norfolk and Suffolk, and parts of Essex. The restrictions follows a number of cases in poultry and wild and captive birds. There are still restrictions in place in Devon, Cornwall, the Isles of Scilly, and parts of Somerset which were announced last month.

Read more: Bird flu pushing poultry businesses to the brink

The UK's deputy chief veterinary officer Richard Irvine is calling on bird keepers to take urgent action. There is currently no end date for the restriction zone with Defra keeping it under regular review. Mr Irvine said all bird keepers, including backyard owners with small numbers of poultry, had to follow 'strict biosecurity measures to help protect their flocks, whatever type or size'.

Keepers with over 500 birds must only allow essential people access to their flock. Workers need to change clothing and footwear before entering enclosures, and vehicles need to be cleaned and disinfected regularly. Whilst the H5N1 strain of the avian influenza virus is highly contagious among birds, the risk to public health from the virus is very low.

The UK’s chief veterinary office Christine Middlemiss, said: "It's a very concerning level of infection out there at the moment. It's certainly unusual to have this many cases confirmed at this time of year. It's a disease we usually see in the winter when migratory birds return from where they've been over the summer.”