Saturday, April 6, 2013

Passing of the pandemic epoch

Don't worry about pandemics ... evolution isn't quite that fast.

One of the great fears among catastrophists, to go with meteor strikes and robots run rampant, is pandemics. Human history is littered with horrible epidemics that decimated (or worse) populations all over the world. Recent episodes like Spanish influenza and HIV are pretty fresh in mind, as is SARs and the ongoing fear of new super-influenza strains coming from the livestock pens of Asia.

One thing all these epoisodes have in common is the movement of pathogens into a new population with relatively little past exposure or resistance. The source of the Spanish influenza is unclear, but HIV clearly jumped the species barrier from chimpanzees to humans roughly in the 1950's, and other plagues and pandemics, such as those that swept through the post-contact Americas, or the black plagues of Europe, came from external sources.

But by this point we have so thoroughly homogenized the world, both in human travel between all points of the compass, and by human invasion of all corners of the natural world, that one can assume that there are no sources of novel pathogens left. That leads me to the conclusion that we have relatively little to fear from future pandemics. A dangerous prediction, to be sure, so I make it with some trepidation. Perhaps it would be better to call it an educated guess.

Future novel pathogens would have to be newly constructed, a far more difficult barrier than one of simple contact between previously remote populations or species. Surely, evolution is always hard at work recombining viral and bacterial genomes to create the next super-bug. But the drama of pandemic is typically counter-productive for the intelligent pathogen. That is why the most feared pathogens, like HIV or plague, are zoonoses- pathogens that inadvertently jumped from the species they were happily adapted to into a different one (us) they were not adapted to and whom they killed in wanton fashion, destroying their own little homes.

Influenza, likewise, comes from birds and / or pigs (as did SARS, from bats), and the same argument applies- that we have been exposed to all accessible wild variants by this time, and the probability of new and dangerous variants arising in these same reservoir species is far lower than the prior chance of contact with existing, host-adapted pathogens.

Another possible source is human inventiveness, now that we can engineer genomes and organisms with some skill. But unlike something like the stuxnet computer virus, a real virus would not be so easily contained, and makes a truly abysmal weapon for anyone but the masochistic psychopath.

Lastly, the growing drug resistance of well-known pathogens like Staphalococcus aureus, malaria, STDs, and tuberculosis are quite a bit more likely to return as public health issues in the future than any exotic pandemic. That medically useful antibiotics or their relatives are still allowed to be used in routine animal feed is appalling, though the problem stems more acutely from overuse in humans, and lack of hygeine in hospitals, of all places.


  • The new atheists ... a bit rude!
  • Oh, those pagan peeps.
  • NCAA players- hung out to dry.
  • Religion pokes its head into economics.
  • Corruption continues, cozily. Lessig on corruption: "we have lost our republic". Yes, our legislative process is completely broken.
  • The real retirement problem? Crappy 401k's, and not enough Social Security.
  • Austerity / neoliberal economics is wrong, wrong, wrong.
  • But for the GOP, shame is not a word in the dictionary.
  • "But employers hope the guest-worker program will also prevent low-wage Americans from getting a raise."
  • Tuna laundering on the high seas.
  • Economic quote of the week, from Jim Chanos on the pervasiveness of fraud in business and corruption in government, in the US:
"One of things we like to say is that in virtually all cases of major financial market fraud over the past 20 years, the only people who really brought forth the fraud into the light were either internal whistleblowers, the press, and/or short-sellers. It was not the normal guardians of the marketplace – regulators, law enforcement, external auditors or people like that — that did it."
  • Economics graph of the week, from JP Morgan (slide 12). Interest rates vs stock performance, indicating that the sweet spot of inflation is about 5%. Below that rate, rising interest rates/inflation correlates with economic growth, while above, it negatively affects the stock market.

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