The Evolution of Antibiotic
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The evolution of antibiotic
resistance in bacterial populations is a direct consequence of natural selection
applied by widespread use of antibiotic drugs. When a new antibiotic is first
introduced, it kills the vast majority of bacteria exposed to it. The surviving
bacterial cells, however, may include individuals whose genomes happen to
include a mutant gene that confers resistance. As Darwin understood, individuals
carrying the resistance gene will leave behind a disproportionately large share
of offspring, which inherit the gene. If the environment consistently contains
an antibiotic, bacteria carrying the resistance gene will eventually come to
predominate. Because bacteria reproduce so rapidly and have comparatively high
rates of mutation, evolutionary change leading to resistant populations is often
rapid.
We have accelerated the pace of the evolution of antibiotic resistance by
introducing massive quantities of antibiotics into the bacteria's environment.
Each year, U.S. physicians prescribe more than 100 million courses of
antibiotics; the Centers for Disease Control estimate that about half of these
prescriptions are unnecessary. An additional 20 million pounds of antibiotics
are fed to farm animals annually. The use of antibacterial soaps and cleansers
has become routine in many households. As a result of this massive alteration of
the bacterial environment, resistant bacteria are now found not only in
hospitals and the bodies of sick people but are also widespread in our food
supply and in the environment. Our heavy use (many would say overuse) of
antibiotics means that susceptible bacteria are under constant attack and that
resistant strains have little competition. In our fight against disease, we
rashly overlooked some basic principles of evolutionary biology and are now
paying a heavy price.
Here is one interesting site (you can find many!) about the effect of antibiotic
resistance and describes a coalition to keep antibiotics working. Take a look
and see if this helps you understand the problem.
http://www.keepantibioticsworking.com/library/uploadedfiles/Antibiotic_Resistance_-_An_Emerging_Public_Hea.pdf
For this paper, please arrange it as you would any formal paper for a college
class. You should always start with some introductory statements. For example,
consider these questions to focus your thoughts:
What is antibiotic resistance?
Why is it a problem?
Next you would give some technical background.
How do antibiotic resistant bacteria arise?
Who is responsible for aggravating the problem?
Then give some recommendations on how to prevent or reduce the problem, or what
specific factors make you believe that this problem cannot be eliminated.
Finally sum up your thoughts.
