Submitted to: Journal of Virology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/8/2002
Publication Date: 6/10/2002
Citation: Tumpey, T., Suarez, D.L., Perkins, L.E., Senne, D.A., Lee, J., Lee, Y., Mo, I., Sung, H., Swayne, D.E. 2002. Characterization of a highly pathogenic h5n1 avian influenza a virus isolated from duck skeletal muscle. Journal of Virology.
Interpretive Summary: Six deaths were recorded from eighteen hospitalized influenza (H5N1) cases in 1997 in Hong Kong and was the first report that a purely avian virus can cause respiratory disease in humans. This outbreak created a new awareness that avian influenza viruses could spread directly from poultry to humans and cause severe disease in humans. Although no influenza H5N1 viruses have ebeen isolated from humans since December 1997, recent virological surveillance has indicated that similar viruses can be still be isolated from poultry in Southeastern China. In April 2001, an avian H5N1 influenza A virus was isolated from duck meat that had been imported from China to Korea. We investigated the molecular characterization and pathogenesis of this recent H5N1 virus isolated from duck meat. Like the Hong Kong H5N1 viruses, this virus was lethal for chickens and induced some mortality in mice. No mortality was observed in experimental ducks, but relatively high levels of infectious virus was detected in duck skeletal muscle and brain tissue isolated shortly after infection. To our knowledge, this is the first demonstration of a H5N1 influenza virus isolated from duck meat and raises important health implications. The.
Technical Abstract: Since the 1997 influenza H5N1 virus outbreak in humans and poultry in Hong Kong, the emergence of closely related viruses in poultry has raised public health concerns. In April 2001, an avian H5N1 influenza A virus was isolated from duck meat that had been imported from China to Korea. Phylogenetic analysis of the hemagglutinin gene of A/Dk/Ag/01 showed that the virus clustered with the H5 Goose/Guandong/1/96 lineage and 1997 Hong Kong human isolates, and possessed an hemagglutinin cleavage site identical to these isolates. Following intravenous inoculation, this virus was highly pathogenic and replicated to high titers in chickens. Although no physical signs of disease were observed in H5-inoculated ducks, infectious virus could be detected in lung tissue, cloacal and oropharyngeal swabs. The DK/Ag/01 virus was unique among the H5 isolates in that infectious virus and viral antigen could also be detected in muscle and brain tissue of ducks at two and four days post-infection. The pathogenesis of DK/Ag/0 virus was further characterized in BALB/c mice. All H5 influenza viruses replicated in mice, but in contrast to the highly lethal CK/HK/220/97 virus, DK/Ag/01 remained localized to the respiratory tract and resulted in 22% mortality. The isolation of a highly pathogenic H5N1 influenza virus from poultry indicates that such viruses are still circulating in southern China and may present a risk for transmission of the virus to humans.