What is antibiotic resistance?

Antibiotic Resistance

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Antibiotic resistance can be explained in many ways, but perhaps the most interesting context within which this can be done is evolutionary biology. Mutations within the bacterial genome, or any genome for that matter, are a fact of life. They happen all the time and can create changes in the phenotype or expressed characteristics. In the case of bacteria, it may be possible for them to develop a mutation that makes them resistant to antibiotic medication. This, of course, depends on the type of bacteria and the mechanism of the medication.

Once the bacteria develops this ability to resist the treatment, it means that the prescribed antibiotic may no longer be effective and it may be possible for the patient to spread the resistant bacteria to others. The variations created by mutation are selected upon by evolution. You may have heard the phrase "survival of the fittest" to describe evolution and, in some ways, this is true. The resistant bacteria have an advantage when the antibiotic is used in the future, because they are resistant and other bacteria are not. Hospitals are perfect environments in which to find the selective pressures that lead to resistance. In order to decrease these selective pressures, it is important that antibiotics only be used when absolutely necessary.

For more information on how antibiotic resistance develops, see the "More Information" link to the left.