H3N2 is a subtype of the species avian influenzavirus (bird flu virus). H3N2 has mutatedinto various strains including the Hong Kong Flu strain (now extinct) and the annual flu.
The annual flu (also called "seasonal flu" or "human flu") kills an estimated 36,000 people in the United States each year. The annual flu vaccineis made by combining vaccines for the new versions of H1N1 and H3N2 viruses that nature produces each year. The dominant strain in January 2006is H3N2. Measured resistance to the standard antiviral drugs amantadineand rimantadinein H3N2 has increased from 1% in 1994to 12% in 2003to 91% in 2005. 
"[C]ontemporary human H3N2 influenza viruses are now endemic in pigs in southern China and can reassort with avian H5N1 viruses in this intermediate host." 
Avian influenza(also known as bird flu, avian flu, influenza virus A flu, type A flu, or genus A flu) is a flu due to a type of influenzavirusthat is hosted by birds, but may infect several species of mammals. The avian influenzavirus subtypes that have been confirmed in humans, ordered by the number of known human deaths, are: H1N1 caused Spanish flu, H2N2 caused Asian Flu, H3N2 caused Hong Kong Flu, H5N1is the current pandemic threat, H7N7, H9N2, H7N2, H7N3.
H3N2 evolved from H2N2 by antigenic shiftand caused the Hong Kong Flupandemic of 1968 and 1969 that killed up to 750,000. (Detailed chart of its evolution here.) "An early-onset, severe form of influenza A (H3N2) made headlines when it claimed the lives of several children in the United States in late 2003." 
The dominant strain of annual flu in January 2006is H3N2. Measured resistance to the standard antiviral drugs amantadineand rimantadinein H3N2 has increased from 1% in 1994to 12% in 2003to 91% in 2005. 
Hong Kong Flu
The Hong Kong Flu was a pandemicoutbreak of influenzathat began in Hong Kongin 1968and spread to the United States of Americathat year. The outbreak ended the following year, in 1969.
The Hong Kong flu was the A type of influenza, specifically the first known outbreak of the H3N2 strain (a notation that refers to the configuration of the hemagglutininand neuraminidaseproteinsin the virus).
Because of its similarity to the 1957Asian Flu(which was the H2N2 strain, differing from the Hong Kong flu only in the chemical arrangement of the hemagglutinin protein as a result of antigenic shift) and possibly the subsequent accumulation of related antibodiesin the affected population, the Hong Kong flu resulted in much fewer casualties than most pandemics. Casualty estimates vary: between 750,000 and two million people died of the virus worldwide (34,000 people in the United States) during the two years (1968-1969) that it was active. It was therefore the least lethal pandemic in the 20th century.
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New Scientist: Bird Flude:Hongkong-Grippe
pt:Gripe de Hong Kong
Categories: Influenza| Pandemics| Health in Hong Kong
This article is licensed under the GNU Free Documentation License.
It uses material from the http://en.wikipedia.org/wiki/H3N2 Wikipedia article H3N2.