4.6.3.7 Resistant Bacteria

Question 1

Why can bacteria evolve rapidly?

Answer 1

bacteria can evolve rapidly because they reproduce at a fast rate

Question 2

What do mutations of bacterial pathogens produce?

Answer 2

mutations of bacterial pathogens produce new strains

Question 3

How does antibiotic resistance in bacteria develop?

Answer 3

• bacteria reproduce at a fast rate
• mutations of bacterial pathogens during reproduction produce new strains (mutations during reproduction can result in new genes e.g. gene for antibiotic resistant)
• exposure to antibiotics creates a selection pressure as those with antibiotic resistant will be resistant to antibiotics and so are not killed and those without antibiotic resistant die
• they survive and reproduce so the population of the resistant strain rises
• the resistant strain will then spread because people are not immune to it and there is no effective treatment

Question 4

Example of bacteria resistant to antibiotics?

Answer 4

• MRSA is resistant to antibiotics
• ‘superbug’ as it is resistant to many dif. types of antibiotics

Question 5

Where is MRSA common?

Answer 5

• MRSA is common in hospitals
• spreads when doctors and nurses move to different patients

Question 6

How do you reduce the rate of development of antibiotic resistant strains?

Answer 6

• doctors should not prescribe antibiotics inappropriately e.g. treating non-serious or viral infections
• patients should complete their course of antibiotics so all bacteria are killed and none survive to mutate and form resistant strains
• the agricultural use of antibiotics should be restricted - farmers currently use antibiotics to prevent their livestock dying from disease, this overuse leads to antibiotic resistant bacteria which are then transferred to humans when they consume meat
• specific antibiotics should be given to specific bacteria

Question 7

How can you slow the transmission of bacteria?

Answer 7

• maintain high standards of hygiene in hospitals
• medical staff and visitors should wash hands regularly
• medical staff should wear disposable clothing or clothing that is regularly sterilised

Question 8

What is the development of antibiotics like?

Answer 8

• the development of new antibiotics is costly and slow
• unlikely to keep up with the emergence of new resistant strains