L6 - Antibiotic Resistance

• The first antibiotic was penicillin. Many other antibiotics have now been discovered.
• Antibiotics kill bacteria.
• Natural antibiotics (produced by microorganisms) have also been altered to make them safer for humans. They are known as semi-synthetic antibiotics.
• Some antibiotics are completely man made and known as synthetic antibiotics.
• Antibiotics do not work on viruses as viruses live inside our cells and we could damage our own tissue.
• Antibiotic Resistance:

  1. Bacteria divide by mitosis
  2. There is a mutation that makes one of the bacteria resistant to an antibiotic
  3. Antibiotics are given which only kill the bacteria which are not resistant
  4. There is now less competition for the mutated bacteria and they reproduce even in the presence of the antibiotic
  5. This happens due to antibiotics being overprescribed in humans and being constantly given to farm animals to prevent infection.
• MRSA is sometimes called a “super bug” by media. It is resistant to several antibiotics.
• To help control the spread of MRSA there are some control measures:

  • hand washing
  • thorough cleaning of hospital wards
  • use of alcohol gels
  • MRSA screening