Swine Flu Genes From Pigs Only, Not Humans or Birds | Wired Science

Swine Flu Genes From Pigs Only, Not Humans or Birds | Wired Science:

"‘The new neuraminidase gene that came in from Eurasian swine is one we’ve never before seen circulating in humans,’ said Rambaut. ‘That’s one of the reasons it’s spreading rapidly. Very few people will have any immunity to this particular combination, which is what gives the concern that this will be a pandemic rather than just a normal seasonal flu outbreak. It remains to be seen how much and to what extent there is existing immunity.’"

Update 2009/04/30: The following article is more recent than the one above, but is it based on the "earlier reports" mentioned in the Wired article?

Technology Review: Hunting for Clues in the Swine Flu Genetic Code:

"The new swine flu virus appears to have done more swapping than usual, with genetic segments from four different sources: North American swine influenza viruses, North American avian influenza viruses, one gene segment from a human influenza virus, and two gene segments that are normally found in swine influenza viruses in Asia and in Europe.

"Parts of it are from the original 1918 virus, parts are similar to the current circulating H1N1 strain from seasonal flu," says Sasisekharan..."