Characterization of an H5N1 avian influenza virus from Taiwan
Journal
Veterinary Microbiology
Journal Volume
124
Journal Issue
44624
Pages
193-201
Date Issued
2007
Author(s)
Abstract
In 2003, an avian influenza (AI) virus of H5N1 subtype (A/Duck/China/E319-2/03; Dk/CHN/E319-2/03) was isolated from a smuggled duck in Kinmen Island of Taiwan. Phylogenetic analysis and pairwise comparison of nucleotide and amino acid sequences revealed that the virus displayed high similarity to the H5N1 viruses circulating in Asia during 2004 and 2005. The hemagglutinin (HA) protein of the virus contained multiple basic amino acid residues (-RERRRKR-) adjacent to the cleavage site between the HA1 and HA2 domains, showing the highly pathogenic (HP) characteristics. The HP phenotype was confirmed by experimental infection of chickens, which led up to 100% mortality within 24-72 h postinfection. The virus replicated equally well in the majority of organs of the infected chickens with titers ranging from 107.5 to 104.7 50% embryo lethal dose (ELD50) per gram of tissue. In a mouse model the virus exhibits low pathogenic characteristics with a lethal infection observed only after applying high inoculating dose (≥107.6 ELD50) of the virus. The infectious virus particles were recovered only from the pulmonary system including trachea and lungs. Our study suggests that ducks infected with H5N1 AIV of HPAI pathotype showing no disease signs can carry the virus silently and that bird smuggling represent a serious risk for H5N1 HPAI transmission. © 2007 Elsevier B.V. All rights reserved.
Subjects
H5N1; Highly pathogenic avian influenza; Interspecies transmission; Surveillance
Other Subjects
amino acid; hemagglutinin; sialidase; virus protein; amino acid sequence; animal experiment; animal model; article; avian influenza; chicken; controlled study; duck; Influenza virus A H5N1; male; mouse; nonhuman; nucleotide sequence; phylogenetic tree; phylogeny; reverse transcription polymerase chain reaction; Taiwan; virus infection; virus isolation; virus particle; virus replication; virus virulence; Amino Acid Sequence; Animals; Base Sequence; Biological Assay; Chickens; Disease Reservoirs; Ducks; Gene Amplification; Hemagglutinin Glycoproteins, Influenza Virus; Influenza A Virus, H5N1 Subtype; Influenza in Birds; Male; Mice; Mice, Inbred BALB C; Molecular Sequence Data; Phylogeny; Polymerase Chain Reaction; Specific Pathogen-Free Organisms; Taiwan; Virulence; Anas; Aves; Avian influenza virus; Gallus gallus
Type
journal article