Grist
Magazine February 25, 2011
http://www.grist.org/article/2011-02-25-flies-cockroaches-antibiotic-resistant-bacteria-factory-farms
Flies
and cockroaches carry
antibiotic-resistant bacteria
from
factory
farms, study
finds
by Tom
Philpott
What sort
of antibiotic-resistant pathogens
are growing on factory
farms,
along with all the cheap pork
chops and chicken wings? And
what level
of threat do they pose to our
health?
Well, we
know that in total, factory-farm
animals consume a
jaw-dropping
four times as many antibiotics as
do people in the
United
States, thanks to diligent
reporting by Maryn McKenna and
Ralph
Loglisci and work by Rep. Louise
Slaughter (D-N.Y.).
And we know
that a kind of
antibiotic-resistant staph
infection
called MRSA
now kills more people than AIDS
-- and infects people who
never set
foot in a hospital, which is the
site where MRSA is thought
to have
originated. We also know, due to
the stellar work of Iowa
State
University researcher Tara Smith,
that pigs in confined animal
feedlot
operations, and the workers who
tend them, routinely carry
MRSA
strains (her paper can be found
here).
We also
know that, by the FDA's own
reckoning, meat on grocery store
shelves is
routinely infected by pathogens
resistant to multiple
antibiotics
(again, McKenna's work brought
the FDA's perhaps
intentionally
obscure report to
light).
And now we
know of yet another means by
which antibiotic-resistant
nasties can
make their way from meat
factories into the broader
community:
through the cockroaches and flies
drawn to the titanic
amounts of
manure produced on factory farms.
For a paper published
last month
in the journal Microbiology,
researchers from North
Carolina
State and Kansas State
universities took one for the
team --
i.e., the
public. They did something few of
us would want to do:
rounded up
common flies and roaches hanging
around factory hog farms,
and tested
them to see what kinds of
bacteria they were
harboring.
Their
finding? More than 90 percent of
the insects sampled carried
forms of
the bacteria Enterococci that are
resistant to at least one
common
antibiotic, and often more than
one. Here's how the authors
summed up
their findings in the paper's
abstract:
This study
shows that house flies and German
[common] cockroaches in
the
confined swine production
environment likely serve as
vectors
and/or
reservoirs of antibiotic
resistant and potentially
virulent
enterococci
and consequently may play an
important role in animal and
public
health.
In a press
release, study coauthor Coby
Schal, entomology professor
at NC
State, broke it down in simpler
terms:
"The big
concern is not that humans will
acquire drug-resistant
bacteria
from their properly cooked bacon
or sausage, but rather that
the
bacteria will be transferred to
humans from the common pests that
live with
pigs and then move in with
us."
Meanwhile,
evidence is mounting that
factory-scale animal farms exact
a high toll
from the people who live around
them in other ways, too.
A study by
University of North Carolina
professor Steve Wing and
others
shows that people with the bad
luck to live near giant hog
farms
suffer demonstrably worse health
when the factories are getting
up to
malodorous stuff like spraying
untreated (and thus
antibiotic-resistant-bacteria-laden)
manure on fields. Among the many
hidden
costs of cheap pork is that
people who live near factory
farms
are doomed
either to be sick or shut in at
certain times of the year.
(McKenna
has an excellent discussion of
the Wing study on her Wired
blog:
http://www.wired.com/wiredscience/2011/02/pig-farms-pollution/
)
To answer
the questions I posed in the
opening paragraph, it seems
we're
brewing up some pretty nasty
pathogens in our meat factories,
along with
all the pork chops and chicken
wings. And they're coming
our way,
carried out on the meat itself,
by factory-farm workers, and
by common
creepy-crawly and flying
insects.
Seems like
there should be a law banning the
non-therapeutic use of
antibiotics
on farms. In 2009, Rep. Louise
Slaughter introduced the
Preservation
of Antibiotics for Medical
Treatment Act (PAMTA). So
far, the
meat industry has managed to,
well, slaughter it. But she
plans to
introduce PAMTA again this
year
