Evidence for Water-Borne Transmission of Highly Pathogenic Avian Influenza H5N1 Viruses

In this study, we isolated 10 H5N1 strains from water samples in Dongting Lake and 4 H5N1 strains from lakeside backyard poultry. These isolates belonged to three distinct clades (clade 2.3.2, 2.3.4, and 7). Phylogenetic analysis showed a diversified genome constellation. The genetic characteristics of some viruses isolated from water samples were extremely similar to those from lakeside poultry. Pathogenic experiments showed that selected represented isolates in this study were highly pathogenic for SPF chickens but had a diversified virulence in mice. The results of our study suggested the potential transmission of avian influenza (H5N1) between the poultry and wild waterfowls and water body around the habitat may play an important role.