A consistent recommendation, or in some cases an absolute directive, by veterinary regulatory authorities in the EU relates to restricting or preventing outside access by flocks. This is based on the fact that the current outbreaks of H5N8 avian influenza are attributed to introduction and dissemination of the virus by migratory and free-living birds through either direct or indirect contact with flocks. Authorities in France, the UK, Holland and Germany have banned outside access on a regional or national basis following outbreaks.
In the 2015 U.S. epornitic, avian influenza in egg-producing flocks was concentrated in a few very large complexes in Iowa, Minnesota and in individual farms in Wisconsin and South Dakota. There were few backyard or semi-commercial flocks identified in outbreaks. The current problem in the EU appears to be associated with free-range flocks which are obviously susceptible to infection.
There have been no late 2016 reports of migratory birds carrying avian influenza along the four U.S. flyways. Notwithstanding this observation, confining flocks should be a major preventive measure from late February onwards. The risk of infection is denoted by isolation of HPAI virus in wild birds applying structured surveillance. Emergence of HPAI can occur at any time during seasonal migration as evidenced by the recent outbreak in Chile.
Why should we expose our entire poultry industry to the risk of HPAI by maintaining 14 million hens under an organic rule which mandates outside access?