Published 14/07/2015

A farm in Lancashire has been hit by an outbreak of avian flu. As a result 170,000 chickens have been culled at Staveley's Eggs, which produces and packages free range and colony cage eggs, in Goosnargh, near Preston.

A 10km surveillance zone and an inner 3km protection zone has been put in place to help prevent further spread. The restrictions mean all poultry farms around the infected premises are not allowed to move poultry, captive birds or other livestock except under licence.

Public Health England has said that the risk to public from this strain is very low, while the Food Standards Agency said there is no food safety risk for consumers.

Are wild birds to blame?

Many are already blaming wild birds for spreading the disease. However, as birds are not currently migrating, it’s unlikely that they are the cause of this outbreak. Intensive indoor farms are ideal incubators for bird flu, as the virus can pass between birds that are kept in close proximity, and should therefore also be considered as a contributing factor.

This current highly pathogenic strain of avian flu causes a high mortality rate in birds, making it highly unlikely that wild birds are responsible for the outbreak. Infected wild animals usually die rapidly, before further spread of the disease is possible.

Our CEO, Philip Lymbery said: “There seems to be this idea that flocks of infected wild birds are dropping disease-ridden faeces like bombs on unsuspecting poultry farms below them. As a result, outdoor poultry are then often shut indoors during an outbreak, despite evidence indicating that disease is most likely to strike in highly intensive indoor farms. Findings have led to calls of a rethink over seeing fully enclosed systems as the best way to protect poultry from disease. Letting birds out where they have a more natural existence seems to be good for their immune system as well as their welfare.”

Intensive farming and bird flu

Bird flu is often grouped into two strains: a high pathogenic strain and a low pathogenic strain. The high pathogenic strain is more serious. Farming a large number of birds in an intensive environment puts birds under stressful conditions and could increase the risk of a highly pathogenic strain.

In intensive farms, thousands of birds are kept crowded together indoors. This causes stress, which can make the birds more vulnerable to infection. An intensive poultry farm provides the optimum conditions for viral mutation and transmission - thousands of birds crowded together in a closed, warm and dusty environment is highly conducive to the transmission of a contagious disease.