“5/05/2009, 11:37am EST”
Swine flu traced to U.S. factory farms
Wired goes where many industry-cheerleading media outlets fear to tread:
At an environmental level, the conditions which shaped H3N2 and H1N2 evolution, and increased the variants’ chances of taking a human-contagious form, are well understood. High-density animal production facilities came to dominate the U.S. pork industry during the late 20th century, and have been adopted around the world. Inside them, pigs are packed so tightly that they cannot turn, and literally stand in their own waste.
Diseases travel rapidly through such immunologically stressed populations, and travel with the animals as they are shuttled throughout the United States between birth and slaughter. That provides ample opportunity for strains to mingle and recombine. An ever-escalating array of industry-developed vaccines confer short-term protection, but at the expense of provoking flu to evolve in unpredictable ways.
h/t Jeremy for the article

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