H9N2 is a subtype of the species avian influenza virus (bird flu virus). In 1999 and 2003, an H9N2 influenza strain caused illness in three people in Hong Kong. Influenzavirus A is a genus of a family of viruses called Orthomyxoviridae in virus classification. ... 1999 (MCMXCIX) was a common year starting on Friday, and was designated the International Year of Older Persons by the United Nations. ... 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ...

"H9N2 influenza viruses of domestic ducks have become established in the domestic poultry of Asia. Phylogenetic and antigenic analyses of the H9N2 viruses isolated from Hong Kong markets suggest three distinct sublineages. Among the chicken H9N2 viruses, six of the gene segments were apparently derived from an earlier chicken H9N2 virus isolated in China, whereas the PB1 and PB2 genes are closely related to those of the H5N1 viruses and a quail H9N2 virusA/quail/Hong Kong/G1/97 (Qa/HK/G1/97)suggesting that many of the 1997 chicken H9 isolates in the markets were reassortants." [1] The human immunodeficiency virus (HIV) A virus is a submicroscopic parasite that infects cells in biological organisms. ... Duck amongst other poultry The Poultry-dealer, after Cesare Vecellio. ... World map showing Asia. ... A phylogeny (or phylogenesis) is the origin and evolution of a set of organisms, usually of a species. ... An antigen is a molecule that stimulates the production of antibodies. ... H5N1 is an avian influenza virus. ... 1997 (MCMXCVII) is a common year starting on Wednesday of the Gregorian calendar. ...

"The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), has issued a task order under an existing contract to Chiron Corporation of Emeryville, CA, for the production of an investigational vaccine based on an H9N2 strain of avian influenza virus that has infected humans and has the potential to trigger a modern-day pandemic." [2] National Institute of Allergy and Infectious Diseases (NIAID) is a component of the National Institutes of Health (NIH), which is an agency of the United States Department of Health and Human Services. ... The National Institutes of Health (NIH) is the primary agency of the United States government responsible for medical research. ... A vaccine is an antigenic preparation used to produce active immunity to a disease, in order to prevent or ameliorate the effects of infection by any natural or wild strain of the organism. ... Binomial name Homo sapiens Linnaeus, 1758 Subspecies Homo sapiens idaltu(extinct) Homo sapiens sapiens Homo (genus). ... A pandemic, or global epidemic, is an outbreak of an infectious disease that affects people over an extensive geographical area (from Greek pan all + demos people). ...

Further reading

• Influenza A (H9N2) infection in a 5-year-old boy - 10 December 2003
• CDC report on Influenza A(H9N2) infections in Hong Kong - 8 April 1999
• Lack of Evidence for Human-to-Human Transmission of Avian Influenza A (H9N2) Viruses in Hong Kong, China, 1999- from Emerging Infectious Diseases, Vol 8, No 2, February 2002