Antibiotic Resistance: Delaying the Inevitable (1 of 2)

Only a few decades ago, antibiotics were considered to be wonder drugs because they worked so well to cure deadly diseases. Ironically, though, many antibiotics have become less effective, precisely because they have worked so well and have been used so often.

Making inroads against infectious disease
The antibiotic era began in 1929 with Alexander Fleming’s observation that bacteria would not grow near colonies of the mold Penicillium. In the decades that followed this breakthrough discovery, molecules produced by fungi and bacteria have been successfully used to combat bacterial diseases such as tuberculosis and pneumonia. Antibiotics drastically reduced death rates associated with many infectious diseases.

Neisseria gonorrhoeaeInfectious diseases
strike back

The golden age of antibiotics proved to be a short-lived one. During the past few decades, many strains of bacteria have evolved resistance to antibiotics. An example of this is Neisseria gonorrhoeae, the bacteria that causes gonorrhea, shown at right. In the 1960s penicillin and ampicillin were able to control most cases of gonorrhea. Today, more than 24 percent of gonorrheal bacteria in the U.S. are resistant to at least one antibiotic, and 98 percent of gonorrheal bacteria in Southeast Asia are resistant to penicillin.1 Infectious bacteria are much harder to control than their predecessors were ten or twenty years ago.

Doctors miss the “good old days,” when the antibiotics they prescribed consistently cured their patients. However, evolutionary theory suggests some specific tactics to help slow the rate at which bacteria become resistant to our drugs.


Neisseria gonorrhoeae image provided by Dennis Kunkel Microscopy, Inc. (www.denniskunkel.com).
1 Center for Disease Control and Prevention’s national profile of the occurrence and rates of gonorrheal infection

 


Find out more about how bacteria stay one step ahead of our antibiotics at pbs.org.
Read the FDA's information on antibiotic resistance.

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