Influenza viruses of two subtypes, H1N1 and H3N2, have been causing respiratory infections in humans since 1977. Before that year, it was believed that only one human subtype circulated each flu season. How did this unusual situation come about? Major changes in the surface glycoproteins of influenza virus - called antigenic shift - lead to worldwide epidemics of influenza known as pandemics. There have been six instances of antigenic shift since 1889. In that year, H2N2 viruses circulated, followed by H3N8 in 1900, H1N1 in 1918, H2N2 in 1957, H3N2 in 1968, and H1N1 in 1977. Each pandemic strain carries HA and NA proteins that have been absent in humans for many years, and therefore immunity is either very low or nonexistent
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No the article does not say
by Nima1 (not verified) on Sat May 02, 2009 05:47 PM PDTNo the article does not say that this flu subtype was genetically engineered; please change the title.
Interesting
by Anonymousity (not verified) on Sat May 02, 2009 09:26 AM PDTThat's an interesting article, and appears to be an informed opinion for a change.
This blog refers to the 1950 virus, but I've also read that attempts have been made to recreate the killer 1918 virus in the lab from dormant samples. Why in God's name would anyone attempt this? It's presented under the guise of research into developing vaccines to prevent future pandemics, but more likely it's research into developing biological weapons. If someone developed and released the 1918 strain we could see tens of millions of deaths.