Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/26/2000
Publication Date: 4/1/2001
Interpretive Summary: In 1997, highly pathogenic (HP) H5N1 avian influenza virus (AIV) caused infections in poultry in Hong Kong and crossed into humans. The virus was very deadly for poultry and threatened to devastate the global poultry industries, especially in the United States. In this study, we developed and tested new and existing inactivated whole influenza virus, subunit H5 and recombinant fowlpox-influenza H5 vaccines for the ability to protect against the Hong Kong H5N1 avian influenza. The vaccines were very effective in preventing disease in poultry. The USA has vaccines that can prevent an H5 influenza disaster in our poultry.
Technical Abstract: In 1997, highly pathogenic (HP) H5N1 avian influenza virus (AIV) caused infections in poultry in Hong Kong and crossed into humans resulting in a limited number of infections including 18 hospitalized cases and six associated deaths. The unique ability of these AIVs to infect both poultry and people raised a concern for the potential of humans to be biological as swell as mechanical vectors of this AIV to poultry. The current study was undertaken to determine if existing vaccines and their technologies could be used during an outbreak to protect poultry. Commercial and experimental inactivated whole H5 AIV and baculovirus-expressed AIV H5 hemagglutinin protein vaccines provided protection from clinical signs and death in chickens following lethal challenge by human-origin HP H5N1 Hong Kong strains 156/97 and 483/97. The commercial and experimental inactivated vaccines had PD50's ranging from 0.25 to 0.89. Furthermore, the vaccines reduced the ability of the challenge AIV to replicate in chickens and decreased the recovery of challenge AIV from the enteric and respiratory tracts. Existing vaccines will protect poultry from this new HP AIV strain which can infect both poultry and humans.