Syllabus Edition

First teaching 2023

First exams 2025

|

Consequences of Antibiotic Resistance (CIE A Level Biology)

Revision Note

Test yourself
Naomi H

Author

Naomi H

Last updated

Consequences of Antibiotic Resistance

  • Antibiotic-resistant strains are a major problem in human medicine; incidence of resistance is increasing due to antibiotic use in humans and in livestock farming when they are not needed
    • By using antibiotics frequently, a selection pressure is exerted on the bacteria, which drives selection of resistant individuals
  • Commonly prescribed antibiotics are becoming less effective against some bacterial strains
  • Some strains of bacteria can be resistant to multiple antibiotics, making diseases very difficult to treat
    • These bacteria are commonly known as superbugs
    • The most common example is a strain of Staphylococcus aureus that has developed resistance to an antibiotic called methicillin, and is now known as MRSA (Methicillin-resistant Staphylococcus aureus)
  • Infections caused by resistant strains of bacteria often need to be treated using multiple antibiotics, resulting in complicated and expensive treatments that may not be available to all

Reducing antibiotic resistance & its impact

  • Ways to prevent the incidence of antibiotic resistance include:
    • tighter controls in countries where antibiotics are sold without a prescription
    • doctors prescribing antibiotics only when needed, e.g. antibiotics not being used for viral infections
    • avoiding the blanket use of ‘wide-spectrum’ antibiotic, and instead prescribing specific antibiotics for different types of infection
    • tighter control of antibiotics in agriculture
  • The spread of already-resistant strains can be limited by:
    • ensuring good hygiene practices, such as handwashing and the use of hand sanitisers, especially in clinical environments
    • isolating infected patients to prevent the spread of resistant strains, in particular in surgical wards where MRSA can infect surgical wounds
  • Scientists need to find new antibiotics to which bacteria have not yet been exposed, as well as antibiotic alternatives, but this process is expensive and time-consuming

You've read 0 of your 5 free revision notes this week

Sign up now. It’s free!

Join the 100,000+ Students that ❤️ Save My Exams

the (exam) results speak for themselves:

Did this page help you?

Naomi H

Author: Naomi H

Expertise: Biology

Naomi graduated from the University of Oxford with a degree in Biological Sciences. She has 8 years of classroom experience teaching Key Stage 3 up to A-Level biology, and is currently a tutor and A-Level examiner. Naomi especially enjoys creating resources that enable students to build a solid understanding of subject content, while also connecting their knowledge with biology’s exciting, real-world applications.