The Evolution of Bacterial Resistance

How do bacteria become resistant to antibiotics?

Many people think that antibiotic resistance is only a problem for people who abuse antibiotic prescriptions, but it's not true. When people don't take antibiotics properly, the health of the entire public is at risk. Even if you haven't taken antibiotics for a long time, an infection caused by resistant bacteria may be more difficult to treat.

When exposed to an antibiotic, bacteria generally have two options -

  1. Mutation - the bacteria change their structure; the antibiotic can no longer permeate the bacteria or bind to the cell surface
  2. Acquire new genes - the bacteria acquire enzymes that de-activate or even destroy the antibiotic

As a result, instead of wiping out the infection altogether, the antibiotic kills only the weaker, non-resistant organisms and leaves their tougher counterparts to multiply and spread the genes that ensured their survival to begin with. Resistance develops over time as new generations of bacteria become stronger - a problem only made worse by the abuse, misuse and overuse of antibiotics.

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Bacteria in Action | Bacterial vs. Viral Infections | Good and Not-So-Good Bacteria | The Evolution of Bacterial Resistance | Bacterial Infection Dictionary