On
June 25, Frederick became the home of the new Jane Hanson…
The dreaded
antibiotic-resistant 'superbug' has arrived. Now what?
·
By Dr. Sara Via and Betsy Nicholas
July 13,
2016
The recent discovery in an American patient of a “superbug” resistant
to colistin, an antibiotic of last resort, is currently rocking the medical
profession. This resistance gene has now been found in several U.S. communities
just a few weeks after its discovery at the end of May at Walter Reed Army
Medical Research Center. The rapid movement of this gene into new populations
illustrates just how easily bacteria can share genes that are advantageous to
them.
Did you know that 70 percent of all medically important
antibiotics used in the United States are given to farm animals that are not
even sick? For decades, it has been common practice to administer low doses of
the same antibiotics used in human medicine to livestock for growth promotion.
Giving low doses to the entire herd on a regular basis is known
to be the fastest way to produce bacterial populations that can resist
antibiotics. This is why the European Union banned the prophylactic use of
antibiotics in 2011.
Despite the importance of this problem, a bill introduced in
Maryland’s General Assembly this year to limit the use of medically important
human antibiotics in farm animals did not even get a vote in either the House
or the Senate. Sponsored by Sen. Paul Pinsky (D-Prince George’s) and Delegate
Shane Robinson (D-Montgomery), this bill would have been a meaningful step in
halting a practice that is known to endanger human health.
After many years of warnings from health professionals about the
dangers of this practice, the FDA released voluntary guidelines in 2015 for
reducing the use of antibiotics in livestock. The FDA guidelines ban the use of
antibiotics for growth promotion, but there is a major loophole — they allow
livestock producers to continue to administer regular low doses of human
antibiotics to animals that aren’t sick for the purpose of “disease
prevention.”
Is it a coincidence that the regimens of antibiotics used for
disease prevention are virtually the same as those previously used for growth
promotion? No medical doctor would prescribe antibiotics to human patients for
disease prevention — they know that the risk of antibiotic-resistant bacteria
is simply too great. Yet the livestock industry finds this practice useful; in
many cases, animals are crowded into unsanitary conditions, and the growth
promotion that occurs as a side effect of “disease prevention” allows animals
to be more quickly brought to market.
We agree that if individual animals in a commercial herd or
flock are sickened with a bacterial infection, they should have access to
veterinary care and appropriate use of antibiotics. We also agree that it is
appropriate to use antibiotics in the event of a major disease outbreak.
However, we note that such outbreaks may be the result of
crowded living conditions in many Concentrated Animal Feeding Operations
(CAFOs).
The routine use of human antibiotics in healthy livestock is a
public health risk for humans for several reasons. First, unlike the animals
with which most of us are familiar, bacteria do not have to inherit genes for
traits (like antibiotic resistance) from parents — they can pass around small
bits of DNA (called plasmids) that carry “useful” genes like those for
antibiotic resistance or the ability to digest different food sources.
These plasmids can even be exchanged between distantly related
bacterial species. Bacteria also have the amazing ability to take up DNA from
other bacteria that have died in the vicinity. Because of these unusual
abilities, if just one bacterial cell has a gene to resist an antibiotic, it
can share it with all of the other bacteria in the host organism and its
environment.
Thus, when antibiotic-resistant bacteria appear in a livestock
herd, they can pass around the gene for resistance to any other bacteria in the
neighborhood. This puts farmworkers and meat packers at tremendous risk.
Farmworkers and farm families in other states have also been found to harbor
bacteria resistant to the antibiotics fed to their livestock.
Secondly, bacteria from livestock operations move directly into
the human community. In Maryland, manure from animals fed a routine diet of
antibiotics may be spread on fields as fertilizer for crops, potentially
contaminating our food with antibiotic resistant bacteria.
In addition, runoff from these fields allows bacteria from the
manure to contaminate our streams and the Bay. A recent study from UMD’s School
of Public Health reports an elevated level of salmonella infections on
Maryland’s Eastern Shore relative to other parts of the state. This was
attributed to contamination of recreational waters and even wells during flooding
after severe rains by bacteria from livestock operations. Although most of
these bacteria just make people sick, some will resist the antibiotics that
will allow them to quickly recover.
This is a problem for all of us.
Medical professionals are becoming increasingly concerned that
the rampant spread of antibiotic resistant bacteria will soon return us to the
pre-antibiotic era, when even the simplest bacterial infection often proved
deadly.
The medical community is working hard to use antibiotics
judiciously in humans. Consumer demand is prompting companies like Perdue to
phase out antibiotics in their products. We can’t wait much longer for the rest
of the agricultural community to follow suit.
We urge policymakers at the state and federal level to take this
issue seriously and eliminate the use of medically important human antibiotics
in farm animals that are not sick.
Dr. Sara Via is a professor of biology and entomology at the
University of Maryland, College Park, and a member of Chesapeake Physicians for
Social Responsibility. Betsy Nicholas is the executive director of Fair Farms,
a campaign for healthy food, land and waterways sponsored by Waterkeepers
Chesapeake.
FrederickNewsPost.com
Donations can be sent
to the Baltimore Nonviolence Center, 325 E. 25th St., Baltimore, MD
21218. Ph: 410-323-1607; Email: mobuszewski [at] verizon.net. Go to http://baltimorenonviolencecenter.blogspot.com/
"The master class
has always declared the wars; the subject class has always fought the battles.
The master class has had all to gain and nothing to lose, while the subject
class has had nothing to gain and everything to lose--especially their
lives." Eugene Victor Debs
No comments:
Post a Comment