April 26, 2009

Most epidemics originate from livestock

It's too early to call the Swine Flu an epidemic, but I'd like to take this opportunity to remind readers that most epidemics throughout human history have originated from domesticated animals.

Measles, smallpox and tuberculosis came to humans from cattle, and the flu originated from pigs and ducks (including the avian flu). Whooping cough (pertussis), which causes 600,000 deaths per year worldwide, comes from pigs and dogs.

Interestingly, it doesn't appear that SARS originated from livestock, but instead from civet cats; that said, the first diagnosed patient was a farmer from Guangdong Province, China.

So not only would the elimination of livestock work to reduce climate change, it would dramatically reduce the chances of diseases being transmitted to human populations.


Michael Kirkland said...

This is one of the central points in Guns, Germs, and Steel. Diamond points out that any society with domesticated animals will necessarily overrun those without because the diseases to which they've developed immunity to will precede them, leaving what appears to be terra nullus.

Not the point you're making, I know, but an important one to consider. Unlike the climate change arguments (which are incremental), everyone, everywhere would have to give up animal husbandry to get the benefits you propose. Further, we'd have to slaughter feral animals that come into regular contact with us, which I do not imagine would be your preference.

Athena Andreadis said...

Michael made one of the points I intended to mention. Another is that the deadliest diseases are actually those transmitted by sexual contact. Should we prohibit sex? Or have sex with a body glove?

On a more serious note, mild forms of pathogens help build up our immune system, as shown by the huge spike in allergies of ultra-sheltered first-world children.