I’m sure lots of other people will point to the new Nature paper on the history and evolution of the new H1N1 influenza.1 (I believe this is an open-access paper, so check it out for yourself.) Key points include:
- it was derived from several viruses circulating in swine
- the initial transmission to humans occurred several months before recognition of the outbreak.
- the reassortment of swine lineages may have occurred years before human emergence
- the nature and location of the genetically closest swine viruses reveal little about the immediate origin of the epidemic
A key conclusion: “Our results highlight the need for systematic surveillance of influenza in swine.” This seems to be becoming fairly widely accepted, though I don’t know what is being done to make it happen.
They include a really helpful diagram, by far the best I’ve seen for clarifying the evolutionary history:
(Sorry for the lack of updates this week, by the way. It’s been a rough week, nothing has gone well except for the Red Sox beating the Yankees in the first two games of their series.)
- Smith, G., Vijaykrishna, D., Bahl, J., Lycett, S., Worobey, M., Pybus, O., Ma, S., Cheung, C., Raghwani, J., Bhatt, S., Peiris, J., Guan, Y., & Rambaut, A. (2009). Origins and evolutionary genomics of the 2009 swine-origin H1N1 influenza A epidemic Nature DOI: 10.1038/nature08182[↩]
the H1N1 or Swine Flu Virus is very scary at first but now it is well controlled by vaccines and prevention by avoiding going into places with incidence of swine flu.
H1N1 or Swine Flu is a bit scary but it a good thing to note that this virus is not that very deadly.
[...] pig was simultaneously infected with North American swine flu and a Eurasian swine flu, the two reassorted so that two of the Eurasian virus’s segments joined with 6 of the North American segments, [...]
[...] H1N1 evolution [...]
My brother got infected with H1N1 or Swine Flu in Mexico. He got a mild fever and luckily he did not die.
If you look at the pandemic of 1977, when H1N1 or Swine Flu re-emerged after a 20 year absence, there is no shift in age-related mortality pattern. The 1977 “pandemic” is, of course, not considered a true pandemic by experts today, for reasons that are not entierely consistent. It certainly was an antigenic shift and not an antigenic drift. As far as I have been able to follow the current events, the most significant factor seems to have been that most people, who were severely affected, were people with other medical conditions.