Evolution and ecology of influenza A virus

The evolution of pandemic influenza A viruses, based on continuing dependence on the aquatic avian gene reservoir, is established. The relationship between the influenza viruses and their host aquatic birds, and how such interactions persisted was discussed. Several conclusions were made based on the phylogenetic analysis of influenza A virus RNA segments for the internal and spike proteins. Among these were the confirmation of a global pool for the influenza virus in aquatic birds and the evolution of host-specific lineages.