1. Antibiotics: From Discovery to Resistance
Buea University Microbiology and Parasitology Student Association (BUMPSA) Symposium
Antibiotics: From Discovery to Resistance By
Nchanji Gordon T.
March 2016

2. BUMPSA SYMPOSIUM March 2016
OUTLINE
Introduction
Fleming and Discovery of Antibiotics
Mechanisms of Action of Antibiotics
AMR (AntiMicrobial Resistance)
Mechanisms of antibiotic resistance
Causes of Antibiotic Resistance
Spread of Antibiotic Resistance
Handling AMR
Implications of AMR
Alternatives to Antibiotics
BUMPSA SYMPOSIUM March 2016

3. Introduction
Compounds which destroy microbes, prevent their multiplication or growth, or prevent their pathogenic action.
Soluble substances derived from a mould or bacterium that inhibits the growth of other microorganisms.
Versus
ANTIMICROBIAL
ANTIBIOTIC
What you need to note from here is that antibiotic and antimicrobial are often used interchangeably.
What was there before antibiotics?
How were infectious diseases cured? Managed?
BUMPSA SYMPOSIUM March 2016

4. Fleming & The Discovery of Antibiotics
Figure 1: Initial plate of Staphylococci plate contaminated with Penicillium noatum
BUMPSA SYMPOSIUM March 2016

5. Fleming & The Discovery of Antibiotics…
This first practical use of penicillin was in the preparation of differential culture medium.
The amazing thing that caught my attention is Fleming had already highlighted this issue of AMR
BUMPSA SYMPOSIUM March 2016

6. Mechanisms of Action of Antibiotics
Table 2: Mechanisms of action of the most frequently used family of antibiotics.
Antibiotic target
Antibiotic family
Cell Wall
Beta-lactams and vancomicin
Cellular membrane
Daptomicin, Polimixin
Inhibiting Protein synthesis
Linezolid, Tetraciclins, Macrolides, Aminoglicosides
Inhibiting Synthesis of DNA/RNA
Fluoroquinolones, Rifamicin
Targeting Metabolic Pathways
Trimetropin, Sulfonamides
BUMPSA SYMPOSIUM March 2016

7. AntiMicrobial Resistance
The World Health Organisation describes Antibiotic Resistance as ‘’one of the greatest threats to human health ‘’
Antibiotic Resistance: Indicates scene where microorganisms continue to multiply although exposed to antibiotic agents.
Antimicrobial drug resistant bacteria Vs Multidrug resistant bacteria?
MDR further complicates the whole story.
BUMPSA SYMPOSIUM March 2016

8. BUMPSA SYMPOSIUM March 2016
Facts about AMR (CDC)
On consumption of antibiotics, sensitive bacteria are killed, but resistant ones may be left to grow and multiply.
Overuse and misuse of antibiotics threatens the usefulness of these important drugs. Decreasing inappropriate antibiotic use is a key strategy to control antibiotic resistance.
Antibiotic resistance can cause significant suffering for people who have common infections that once were easily treatable with antibiotics.
When antibiotics do not work, infections often last longer, cause more severe illness, require more doctor visits or extended hospital stays, and involve more expensive and toxic medications. Some resistant infections can even cause death.
BUMPSA SYMPOSIUM March 2016

9. Antibiotics and their journey from discovery to resistance
Figure 2:Timeline of antibiotics discovery and the development of antibiotic resistance
BUMPSA SYMPOSIUM March 2016

10. Mechanisms of antibiotic resistance?
Figure 4: Genetic basis of AMR?
Figure 3: How AMR comes about?
BUMPSA SYMPOSIUM March 2016

11. Mechanisms of Resistance of Antibiotics
Modify cell surface receptors
Prevent entry/accumulation of antibiotic
Metabolic bypass
Inactivation of the antimicrobial agent
Biofilm formation
BUMPSA SYMPOSIUM March 2016

12. Causes of Antibiotic Resistance
Underdosage
One other thing which further complicates antibiotic resistance is the ability of bacteria to transmit this drug resistant genes to competent organisms in the microbial community
Figure 5: WHO infographic about causes of AMR
BUMPSA SYMPOSIUM March 2016

13. Spread of AnitiMicrobial Resistance
This can also occur via
Environment (Air, Water, Soil)
Fomites
Infected individuals
Figure 6: Some routes through which AMR spreads
(Source: CDC)
BUMPSA SYMPOSIUM March 2016

14. BUMPSA SYMPOSIUM March 2016
Handling AMR
Antibiotic combination therapies
Antimicrobial nanotechnology
Phage therapy
BUMPSA SYMPOSIUM March 2016

15. BUMPSA SYMPOSIUM March 2016
Implications of AMR
Higher morbidity and mortality caused by these agents
Higher burden of healthcare cost for the patient
Increase economic loss in agricultural sector, especially in the animal husbandry sector and industry
BUMPSA SYMPOSIUM March 2016

16. Alternatives to Antibiotics
Probiotics
Vaccination
Antimicrobial nanoparticles
Microbial therapeutic enzymes
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17. BUMPSA SYMPOSIUM March 2016
Take home messages
BUMPSA SYMPOSIUM March 2016

18. BUMPSA SYMPOSIUM March 2016
Sources
Prescott, M. L., Harley, P. L. and Klein, A. D. (2002). Microbiology. The McGraw−Hill Companies, 5th edition.
BUMPSA SYMPOSIUM March 2016

19. Thank you for listening
BUMPSA
HEALTH AWARENESS AND SERVICE TO MANKIND
BUMPSA SYMPOSIUM March 2016