Whilst wild birds may have played a role in the spread of H5N1, they are far from being the main culprits. Following the discovery of H5N1-infected migrating wild birds in Qinghai Lake, China in 2005, migrating wild birds were assumed to be the key responsible agents for carrying the virus across to Europe, Africa and the Middle East. However, the geographic spread of the disease correlates with major road and rail routes rather than migratory routes or seasons (The Lancet Infectious Diseases 2006). Furthermore, recent molecular and phylogenetic analysis of H5N1 has found that different geographical regions have.
