by Michael Greger, M.D.
www.veganMD.org
4/13/03
Animal agriculture is not just a public health hazard
for those who consume meat. In fact, the single worst epidemic
in recorded world history, the 1918 influenza pandemic,
has been blamed on the livestock industry.[1] In that case,
the unnatural density and proximity of ducks and pigs raised
for slaughter probably led to the deaths of 20 to 40 million
people across the world.[2] Since then, the raising of pigs
and poultry has resulted in millions more human deaths from
the 1957-58 Asian flu, the 1968-69 Hongkong flu and the
1977 swine flu.[3] All of these influenza strains seem to
have arisen in the same region of southern China where intensive
systems of animal agriculture have become a breeding ground
for new killer viruses.[4]
For centuries, the Guangdong province of China has had the
world's largest concentration of humans, pigs and fowl living
in close proximity.[5] In this environment, pigs can become
co-infected with both human and avian (bird) strains of
influenza. When this happens, a deadly gene swapping can
take place, in which the lethality of viral strains rampant
in the Chinese poultry industry[6] can combine with the
human transmissibility of the human strains to create new
mutated flu viruses capable of infecting and killing people
on a global scale.[7]
Other viral threats besides influenza have also escaped
from Southeast Asian livestock operations. In 1999, a new
virus, now known as the Nipah virus, jumped from pigs to
humans in Malaysia, infecting pig breeders and killing about
a hundred people before it was stamped out.[8] In the Southern
Chinese province of Guangdong, battery chickens are sometimes
kept directly above pig pens, depositing their waste right
into the pigs' food troughs.[9] It may come as no surprise,
then, that Guangdong is thought to have been ground zero
for the deadly SARS virus as well.[10] The Severe Acute
Respiratory Syndrome (SARS) virus is just the latest in
a string of human tragedies traced back to our appetite
for animal flesh.
According to the World Health Organization, SARS, which
has already infected thousands worldwide, could become the
“first severe new disease of the 21st century with
global epidemic potential."[11] And experts are again
blaming intensive animal agriculture.[12,13,14,15] According
to China’s equivalent of the Centers for Disease Control,
the first people to succumb to the SARS virus were bird
vendors and chefs, who had been in close and continued contact
with chickens, ducks and other birds.[16]
Scientists have identified SARS as a coronavirus, a class
of viruses well known to the livestock industry.[17] Coronaviruses
are found in many feedlot cattle who die of pneumonia and
are responsible for the respiratory disease known as shipping
fever in cattle stressed by transport.[18] There’s
currently a new mutant strain of coronavirus causing outbreaks
of a contagious pneumonia on pig farms in several countries.[19]
Preliminary work, though, suggests the SARS virus is more
related to the one that causes lung infections in chickens.[20]
The concentration of animals with weakened immune systems
in unsanitary conditions seems inherent to factory farming.
As intensive livestock operations continue to spread worldwide,
so will viral breeding grounds.[21] Moving away from intensive
animal agriculture and towards more sustainable plant-based
methods of production may benefit the health of the planet
and its inhabitants in more ways than we know.
[1] Daily GC, Ehrlich PR. Development, Global Change, and
the Epidemiological Environment. Stanford, CA: Stanford
University; 1995. Paper #0062.
[2] Kiple KF, editor. The Cambridge World History of Human
Disease. Cambridge: Cambridge University Press; 1993.
[3] The Straits Times (Singapore) ,March 21, 2003.
[4] Ibid.
[5] Time, April 7, 2003.
[6] The Straits Times (Singapore), March 21, 2003.
[7] Courier Mail (Australia) ,April 12, 2003.
[8] South China Morning Post, April 9, 2003.
[9] Sydney Morning Herald, April 7, 2003
[10] Time, April 7, 2003.
[11] The Atlanta Journal and Constitution, April 12, 2003.
[12] TB & Outbreaks Week, April 15, 2003.
[13] The Toronto Sun, March 28, 2003.
[14] New Scientist, April 03, 2003.
[15] Courier Mail (Australia), April 12, 2003.
[16] The Michigan Daily, April 09, 2003.
[17] New England Journal of Medicine, April 10, 2003.
[18] Santa Fe New Mexican (New Mexico), April 6, 2003.
[19] Ibid.
[20] New Scientist, April 03, 2003.
[21] Time, April 7, 2003.
United
Poultry Concerns, Inc.