ABSTRACT
Four H7N3 avian influenza viruses (AIVs) were isolated from domestic ducks in live-poultry markets in Zhejiang Province, Eastern China, in 2011. All viruses were characterized by whole-genome sequencing with subsequent phylogenetic analysis and genetic comparison. Phylogenetic analysis of all eight viral genes showed that the viruses clustered in the Eurasian lineage of influenza viruses. The hemagglutinin cleavage site of all viruses indicated that the four strains were low-pathogenic avian influenza viruses.
Subject(s)
Ducks/virology , Genome, Viral , Influenza A Virus, H7N3 Subtype/genetics , Influenza A Virus, H7N3 Subtype/isolation & purification , Influenza in Birds/epidemiology , Phylogeny , Sequence Analysis, DNA , Amino Acid Sequence , Animals , China/epidemiology , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Influenza A Virus, H7N3 Subtype/classification , Influenza in Birds/virology , Molecular Sequence Data , Neuraminidase/genetics , Poultry , Poultry Diseases/epidemiology , Poultry Diseases/virologyABSTRACT
This study describes the characterization of seven H5N1 avian influenza viruses from domestic ducks in Eastern China in 2011. Phylogenetic analysis showed these viruses were closely related to an H5N1 virus circulating in wild birds in Hong Kong. Some characteristics of these viruses were similar to those of an H5N1 strain that circulated in China and Vietnam (2003-2004). The virulence of three isolates was examined in chickens and mice, and they were found to be highly pathogenic in chickens but showed low pathogenicity in mice. These results suggest that continued H5N1 surveillance in poultry should be used as an early warning system for avian influenza outbreaks.
