When Antibiotics Don't Work
It is hard to imagine that just a little more than 50 years ago
most people knew nothing of antibiotic medications and now almost
everyone, including children, know that antibiotics are medicines used
to treat bacterial infections. These
medications range from treatments for strep throat, pneumonia, acne to
meningitis and tuberculosis. Antibiotics
are medications that have been designed to kill or harm bacteria, but
they do not treat viruses.
Bacteria are remarkably adaptive to their environment and that may
include an environment of antibiotics.
These single celled organisms contain genes that create these
adaptations. These are
survival adaptations and bacteria quickly discover that antibiotics
are harmful to them. Consequently
some bacteria develop or call upon already developed resistance genes
to create a mechanism to defeat the antibiotic.
Bacteria can acquire these genes for resistance in three ways.
They may develop a spontaneous gene mutation change in DNA that
results in antibiotic resistance or they may transfer resistance genes
to another bacteria in a form of microbial sects called
transformation. Thirdly,
one of the most frightening ways is by acquiring a gene from a small
circle of DNA called a plasmid. Plasmids
can transfer resistance genes among many, many different types of
bacteria. Plasmids were
the cause of the diarrhea epidemic in Guatemala in 1968 that killed
12,500 people. The
bacteria responsible for this epidemic was resistant to four
antibiotics.
Our world is now beginning to see the threat of incurable bacterial
infections that could lead to an international public health
nightmare. We already
have some bacterial species that are capable of causing
life-threatening illness and that resist every clinically available
antibiotic in the physician’s armamentarium.
The problem of antibiotic resistance is an exceedingly complex one
that does not have a simple solution.
When antibiotics are used in a preventative way or when they
are used in too high of doses or for too long, they may kill off
normal bacteria that would otherwise “crowd out” the
life-threatening antibiotic-resistant bacteria.
Other factors that have contributed to this problem include the
broad preventative use of antibiotics in livestock farming and
agriculture. Even jet
travel plays a role in this as this has allowed the organisms like
antibiotic-resistant tuberculosis to be spread to many different parts
of the world. Reversal of
antibiotic-resistant bacteria requires a new awareness of the broad
consequences of antibiotic use. We
must learn to accept that some bacteria are normal beneficial
components of our world and we must make decisions about our use of
antibiotics that will preserve these normal bacteria that resist the
overrun of resistant bacterial strains.
This will surely require the cooperation among many countries
around the globe to educate their populations about the impact of
improper antibiotic use and resultant antibiotic-resistant bacteria.
Remember, antibiotics save lives.
Take them wisely---don’t take them for granted.
Worldwide Web Resources
Scientific American
www.sciam.com/1998/0398issue/0398levy.html
This
web page provides a reprint of a recent very informative article in
the Scientific American entitled “The Challenge of Antibiotic
Resistance”.
Resistance Web
www.Resistanceweb.mfhs.edu/cit/Index.asp
The purpose of Resistance Web is to share timely,
useful data on bacterial resistance with clinicians and researchers,
to assist in the process of resistance awareness. |