One of the big issues with the 2001 foot-and-mouth disease outbreak was whether vaccination should have been used on livestock to contain the disease.

With avian flu now confirmed in a swan in Scotland, the same arguments are emerging again.

DEFRA does not see vaccination as having a big role should the disease get into the commercial poultry flock.

Instead, its contingency plan consists of movement controls and mass culling of both infected birds and dangerous contacts.

While DEFRA acknowledges there is provision to use vaccination, and says it may have a strategic role to play, it sees limitations.

The vaccines available are “inactivated” types and need to be delivered by injecting birds individually.

It can take up to three weeks for birds to develop protective immunity and some poultry require two doses, raising significant logistical difficulties.

And while these vaccines protect against disease, they will not prevent the birds becoming infected and shedding virus, which could cause infection in others.

Although there are strategies to differentiate vaccinated birds from infected birds, it is still difficult to identify birds carrying the virus.

But organic body the Soil Association believes there is still a strong case for using vaccination in the fight against avian flu.

It accepts that, in the event of a UK outbreak, infected flocks should be culled.

“However, we would then like to see vaccination used to ring-fence the infected area, creating a barrier of immunity to slow the disease,” says Soil Association director Patrick Holden.

He accepts mass vaccination would be difficult, with the whereabouts of many small hobby flocks being unknown.

“It is also arguable that mass vaccination could encourage farmers to relax biosecurity measures,” he says.

But urgent action is needed to at least produce sufficient stocks of vaccine and to train those who would administer it.

“Without this stockpile, we are in danger of seeing a repeat of the foot-and-mouth scenario, where MAFF was unable to change policy, even though the disease was out of control.”

As for the practicality of vaccinating birds, Mr Holden believes logistical problems are not insurmountable.

There are precedents; for example, during outbreaks of poultry diseases, such as Gumboro, birds have been vaccinated.