Avian Influenza in Hong Kong 1997–2002

In 1997, a high-pathogenicity H5N1 avian influenza virus caused serious disease in both man and poultry in Hong Kong, China. Eighteen human cases of disease were recorded, six of which were fatal. This unique virus was eliminated through total depopulation of all poultry markets and chicken farms in December 1997. Other outbreaks of high-pathogenicity avian influenza (HPAI) caused by H5N1 viruses occurred in poultry in 2001 and 2002. These H5N1 viruses isolated had different internal gene constellations to those isolated in 1997. No new cases of infection or disease in man due to these or other H5N1 viruses have been reported. This paper provides an overview and chronology of the events in Hong Kong relating to avian influenza, covering the period from March 1997 to March 2002.