Antibiotic resistance

• Some strains of bacteria are resistant to certain antibiotics. This means that these antibiotics cannot kill them.
• MRSA

  • MRSA is often called a “superbug” because it is resistant to many antibiotics.
• How to stop antibiotic resistance?

  • To help prevent strains of resistant bacteria from developing:
  • Doctors should only prescribe antibiotics if they are needed and not for minor infections or viral infections.
  • Patients should complete their course of antibiotics to ensure all bacteria are killed.
• Bacteria can become resistant to antibiotics.
• Random mutations

  • Within a population of bacteria, some will have random mutations (random change in DNA).
  • The mutated bacteria are resistant to antibiotics and so they are able to survive, whilst the non-resistant bacteria die.
• Natural selection

  • The resistant bacteria can reproduce rapidly because their competition (the non-resistant bacteria) has been destroyed by the antibiotic.
  • When the resistant bacteria reproduce, they produce genetically-identical copies. These copies will all be resistant to the antibiotics.
• In a population of bacteria, a random mutation can arise, which makes that bacteria more resistant to antibiotics. The resistant bacteria reproduce asexually, so the copies will be genetically identical.