Antimicrobial resistance

Question 1

What are antimicrobials?

Answer 1

Chemicals that either kill or prevent the growth of microbes such as bacteria, viruses, fungi and protozoa

Question 2

What are some lesser-known uses of antimicrobials?

Answer 2

• Chopping boards
• Dish cloths
• Work surfaces
• Fridges
• Disinfectants

Question 3

What is antibiotic resistance?

Answer 3

Bacteria can develop resistance through genetic mutation
Mutations then enable the bacteria to alter the way it interacts with the antibiotic
These changes may then make the antibiotci ineffective

Question 4

What does bacteriostatic mean?

Answer 4

Stops the growth of bacteria

Question 5

What does bacteriocidal mean?

Answer 5

Kills bacteria

Question 6

Name 5 reasons why antimicrobial resistance has emerged

Answer 6

• Over use of antibiotics
• Ineffective antibiotics
• Illegal use of antibiotics
• Not completing the course of antibiotics
• Evolutionary pressures

Question 7

What is transformation?

Answer 7

The uptake of free DNA in the environment, the free DNA usually comes from the breakdown of dead bacteria nearby

Question 8

What is conjugation?

Answer 8

The transfer of plasmids, or small circular pieces of bacterial DNA, containing resistance genes from one bacteria to another

Question 9

What is transduction?

Answer 9

The transfer of bacterial DNA via viruses or bacteriophages to other closely related bacteria
Bacteriophages are viruses that only infect bacteria

Question 10

What are ESBL’s?

Answer 10

Extended- Spectrum Beta-Lactamases are enzymes that can be produced by bacteria making them resistant to cephalosporins
resistance is either plasmid or chromosonally encoded

Question 11

What are the 5 different types of resistance?

Answer 11

• Innate, natural or intrinsic resistance
• Mutational resistance
• Extrachromosonal, chromosonal/ acquired resistance
• Phenotypic/ Persister state
• Physical mechanisms of resistance

Question 12

Name 5 mechanisms of resistance

Answer 12

• Enzymatic destruction (bacteria produces an enzyme that destroys the antibiotic)
• Altered permeability (protein is produced to reduce/ block the uptake of the antibiotic into the cell)
• Biofilms- phenotypic resistance
• Swarming- phenotypic resistance
• Efflux(of the antibiotic)- bacteria develop methods to throw antibiotics out of the cell

Question 13

Name 3 substances that can destroy antibiotics

Answer 13

• Aminoglycosides
• Beta-lactamases
• Chloramphenicol

Question 14

Name an enzyme that causes an alteration in bacterial permeability

Answer 14

Beta-Lactamase

Question 15

What is Cross Resistance?

Answer 15

A single mechanism that confers resistance to multiple antimicrobial agents

Question 16

What is Multiple resistance?

Answer 16

Multiple resistance implies that multiple mechanisms are involved

Question 17

What is MAR/ Multiple antimicrobial resistance?

Answer 17

Chromosonally enocded systems involved in low level resistance of bacteria to different classes of antibiotics

Question 18

What is MPC/ Mutant Prevention Concentration

Answer 18

The lowest concentration of antibiotic to inhibit the emergence of mutants

Question 19

Name 5 ways antibiotics can be administered to animals

Answer 19

• By injection
• Topical
• Oral
• In Feed
• In water

Question 20

Why would ESBL’s be a concern?

Answer 20

• Resistance can be carried on a plasmid
• The plasmids are highly promiscuous
• The plasmids confer a fitness advantage
• The plasmid DNA could survive in the environment