Avian influenza in Hong Kong

The Agriculture, Fisheries and Conservation Department (AFCD, http://www.afcd.gov.hk/) of the government of Hong Kong recently reported outbreaks of avian influenza in two chicken farms in Hong Kong (1), as well as sporadic infections in wild fowl found dead in Hong Kong (2). As a result, control measures have been implemented. These included the slaughter of around 16 000 chickens, closure and disinfection of one of the live poultry markets which had contact with the farms and the halting of imports of chickens from mainland China (3). The virus has been partially typed and found to be influenza A (H5). The virus is not the same strain of influenza A (H5N1) (4) that crossed over to humans in 1997, causing six fatalities (5). Outbreaks of avian influenza due to influenza A (H5N1) viruses occurred in poultry in Hong Kong in May 2001 and February 2002, resulting in culls of about one million chickens on each occasion. Neither of these outbreaks was associated with transmission to humans. The last reported incident of transmission of avian influenza (H9N2) to humans was in 1999 in two young children in Hong Kong and the resulting illness was reported to be mild and self limited (6).