Resistant bacteria

• Some bacteria might become resistant to certain antibiotics, such as penicillin, and cannot be destroyed by the antibiotic.
• The main steps in the development of resistance are:

  1. random mutations occur in the genes of individual bacterial cells
  2. some mutations protect the bacterial cell from the effects of the antibiotic
  3. bacteria without the mutation die or cannot reproduce when the antibiotic is present
  4. resistant bacteria can reproduce with less competition from normal bacterial strains
• In order to reduce the rate of development of antibiotic resistant strains:

  • doctors should not prescribe antibiotics inappropriately, such as for the treatment of non-serious infections
  • patients should always complete the full course of antibiotics to ensure all bacteria are killed and none do not survive to mutate and form resistant strains
  • the agricultural use of antibiotics should be restricted
• The number of resistant strains has increased, partly due to the misuse of antibiotics. This has resulted in more infections that are difficult to control.