For years before the current outbreak, scientists openly worried that CAFOs (concentrated animal feedlot operations) provided excellent arenas for the generation and spread of dangerous new flu varieties.
Yet another bit of evidence on this score crossed my desk this week: a “News Focus” piece that ran in Science back in 2003 called “Chasing the Fickle Swine Flu.” (PDF) It’s jumping-off point is the very incident Foer pointed to on Ellen—the outbreak of a novel strain of flu, genetically related to the current strain, on a North Carolina farm in 1998. The opening is worth quoting at length:
One of the first signs of trouble was a barking cough that resounded through a North Carolina farm in August 1998. Every pig in an operation of 2400 animals
sickened, with symptoms similar to those caused by the human flu: high fever, poor appetite, and lethargy. Pregnant sows were hit hardest, and almost 10% aborted
their litters, says veterinary virologist Gene Erickson of the Rollins Animal Disease Diagnostic Laboratory in Raleigh. Many piglets that survived in utero were later born small and weak, and some 50 sows died.
The culprit, a new strain of swine influenza to which the animals had little immunity, left veterinarians and virologists alike puzzled. Although related flu strains in birds, humans, and pigs outside North America constantly evolve, only one influenza subtype had sickened North American pigs since 1930. That spell was suddenly broken about 4 years ago, and a quick succession of new flu viruses has been sweeping through North America’s 100 million pigs ever since. This winter, for example, up to 15% of the 4- to 7-week-old piglets on a large Minnesota farm died, even though their mothers had been vaccinated against swine flu, says veterinary pathologist Kurt Rossow of the University of Minnesota, Twin Cities. [Emphasis added.]
Here we have a phenomenon I’ve written about before: the flu strains circulating through the U.S. swine herd didn’t mutate much after 1930—until 1998. The novel strain that emerged in a North Carolina CAFO then was devastating for pigs, whose immune systems did not recognize it; but luckily, it didn’t have the genetic chops to jump to humans.
By 2003, scientists were actively worried that would soon change, the Science article reveals.
“Within the swine population, we now have a mammalian-adapted virus that is extremely promiscuous,” one researcher told the magazine. “We could end up with a dangerous virus,” i.e., a mutation that jumps to humans.
And researchers were looking to the CAFO as the site where such a thing could rear up. In the 1990s, hog farming underwent an unprecedented process of intensification and consolidation. As Science put it:
In the past decade, big swine producers have gotten bigger, and many small producers have gone out of business. The percentage of farms with 5000 or more animals surged from 18% in 1993 to 53% in 2002, according to Rodger Ott, an agricultural statistician at the National Agricultural Statistics Service in Washington, D.C.
Back in 2003, there was no taboo about stating the obvious:
Wow... Fascinating. Frightening. Maddening. Is it surprising that people saw the writing on the wall and did little to stop the problem, causing senior citizens and other high risk folks in the fall of 2009 to spend their mornings elbow to elbow on line waiting for their H1N1 vaccinations?“With a group of 5000 animals, if a novel virus shows up, it will have more opportunity to replicate and potentially spread than in a group of 100 pigs on a small farm,” [University of Minnesota veterinary pathologist Kurt] Rossow says.
Swine flu seems to be yet another instance of humanity's polluting, unsustainable activities coming back to bite us in the ass. The irony is -- we're lucky it's not nearly as virulent as the 1918 bird blue, which from everything I've read, was shockingly lethal in comparison to H1N1.
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