Avian world poised for emergency action

Bird-keepers and vets across the UK will be braced to put contingency plans into place in an attempt to stem the spread of bird flu.

A three-kilometre-radius protection zone will be set up around the site where the infected swan was found, encircled by a 10-kilometre-radius surveillance zone.

Vets will check birds within these zones for signs of bird flu. Movement of eggs and poultry within the surveillance zone will be restricted.

If the H5N1 virus is confirmed in the UK, poultry and captive birds will be moved indoors in an effort to stop the infection spreading.

If the virus is detected in poultry then a short-term national movement ban on birds and hatching eggs will be brought in as a precaution while the outbreak is investigated.

Low-risk movements would still be permitted under licence.

All poultry kept on a premises confirmed as infected will be culled.

Culling or “slaughter on suspicion” may be ordered at a premises if there is a strong suspicion of avian flu and a high likelihood that it could spread.

Premises in areas where birds are at low risk of exposure to the virus will have restrictions imposed for 21 days while checks are carried out.

Keepers with 50 or more birds are now listed on a compulsory register set up by Defra last year.

Free-range farmers who are forced to move their birds indoors will be allowed to keep their poultry and eggs’ free range status for a limited period.

Mass bird vaccination is not expected to be part of Britain’s bird-flu control strategy, although the government has not officially ruled it out.

The drawbacks to vaccination are that birds must be injected individually, with some poultry requiring two doses for it to be effective.

It could take up to three weeks for birds to develop optimum protection, and vaccinated birds can still spread the disease even though they do not develop symptoms.

The British government’s chief scientific adviser earlier ruled out the use of currently available bird-flu vaccines in the event of a UK outbreak.

Professor Sir David King said rare breeds of birds kept in zoos would be the only cases where vaccines would be feasible. The inoculation of organic or free-range birds would not be recommended.

Speaking after the National Farmers Union’s annual conference in February, he said: “I would be very concerned about the spread with the current vaccine.

"What it means is that every time you vaccinate you have to increase surveillance because signs of the disease are not very obvious.

“We have a very large number of organic and free-range poultry farmers in the UK and that would make surveillance very, very difficult or extremely expensive.”