|
| Doctors have become increasingly concerned by the problem of "super-bugs" -
bacteria that have become resistant to standard antibiotics. It is well known
that a high rate of antibiotic prescribing in hospitals contributes to the
emergence of drug resistant bacteria. But for some antibiotics, an even more
important factor contributing to such emergence, argues a team of researchers in
the open access international medical journal PLoS Medicine, is the use of
antibiotics in agriculture.
"Evidence suggests that antibiotic use in agriculture has contributed to
antibiotic resistance in the pathogenic bacteria of humans," say David Smith of
the Fogarty International Center, Jonathan Dushoff of Princeton university and
the Fogarty International Center, and J.Glenn Morris Jr. of the university of
Maryland.
Antibiotics and antibiotic resistant bacteria are found in the air and soil
around farms, in surface and ground water, in wild animal populations, and on
retail meat and poultry. These resistant bacteria are carried into the kitchen
on contaminated meat and poultry where other foods are cross-contaminated
because of common, unsafe handling practices. Following ingestion, bacteria
occasionally survive the formidable but imperfect gastric barrier to colonize
the gut - which in turn may transmit the resistant bacteria to humans.
Smith and colleagues say that the transmission of antibiotic resistant bacteria
from animal to human populations is difficult to measure, as it is "the product
of a very high exposure rate to potentially contaminated food, and a very low
probability of transmission at a given meal." Nevertheless, based on the
analysis presented in PLoS Medicine, the authors suggest that "transmission from
agriculture can have a greater impact on human populations than hospital
transmission."
After first Denmark and then the European Union banned the use of antibiotics
for growth promotion, say the authors, the prevalence of resistant bacteria
declined in farm animals, retail meat and poultry, and within the human general
population. This provides evidence that antibiotic resistant bacteria can move
between animals and humans.
The exact effects of agricultural antibiotic use on human health remain
uncertain, they say, despite extensive investigation. "But the effects may be
unknowable, unprovable, or immeasurable by the empirical standards of
experimental biology." Given all of this uncertainty, Smith and colleagues
suggest that adopting a "precautionary approach" - such as the European Union
ban - would be suitable.
###
Citation: Smith DL, Dushoff J, Morris G Jr (2005) Agricultural antibiotics and
human health. PLoS Med 2(8): e232.
About PLoS Medicine
PLoS Medicine is an open access, freely available international medical journal.
It publishes original research that enhances our understanding of human health
and disease, together with commentary and analysis of important global health
issues. For more information, visit http://www.plosmedicine.org
About the Public Library of Science
The Public Library of Science (PLoS) is a non-profit organization of scientists
and physicians committed to making the world's scientific and medical literature
a freely available public resource. For more information, visit
http://www.plos.org
Alan
http://veloceraptor.blogspot.com/
http://theoriginalfirebird.blogspot.com/
http://lordcerneabbastoo.blogspot.com/
http://www.stopwar.org.uk/
http://www.700women.org/
|
|