[Highly pathogenic influenza A/H5N1 virus-caused epizooty among mute swans (Cygnus olor) in the lower estuary of the Volga River (November 2005)].

Molecular virological studies of the field material collected in the epicenter of epizooty with high mortality among mute swans (Cygnus olor) in the area of the lower estuary of the Volga River (November 2005) could establish the etiological role of highly pathogenic influenza A (HPAI) virus of the subtype H5N1. Ten HPAI/H5N1 strains deposited at the State Collection of Viruses of the Russian Federation with the priority dated December 1, 2005 were isolated from the cloacal/tracheal swabs and viscera of sick and freshly died mute swans. Complete nucleotide sequences of all fragments of the genome of 6 strains have been deposited in the Gene Bank. The paper discusses the molecular genetic characteristics of isolated strains.