Do we know whether wild birds have spread HPAI H5N1 from SE Asia to Russia, Europe and Africa?
We cannot know with certainty how each outbreak of Asian lineage HPAI H5N1 has originated – there are a number of ways in which the virus could spread. It is likely that H5N1 has spread through and beyond SE Asia primarily as a result of movements of infected poultry and poultry products, but some of the spread is probably also the result of movements of infected wild birds or cage birds. However, the spread from Eastern Europe through to Western Europe appears to be linked to transmission by infected wild birds, particularly wild swans.
