Week 8 - Infection prevention and microbial stewardship

Question 1

What is an outbreak?

Answer 1

-Two or more cases linked in time and place

Question 2

What id Epidemic?

Answer 2

-Infection rate greater than usual background rate

Question 3

What is pandemic?

Answer 3

-Very high rate of infection spreading across many regions, countries and continent

Question 4

What is direct spread?

Answer 4

-One person gives the infection to 1 or more people directly

Question 5

What is indirect spread?

Answer 5

-The use of a vector is needed to spread the infection

Question 6

What is the basic reproduction number?

Answer 6

-Average number of cases one case generates over the course of its infectious period in an otherwise uninfected, non-immune population

Question 7

What host factors can lead to a new outbreak?

Answer 7

• New patients eg number of non-immunes increases (neonates)

- Increased susceptility eg incidence of co morbidity increases eg malignancy, DM

Question 8

Discuss some pathogen factors which can lead to an outbreak

Answer 8

• New pathogen eg new antigens in antigenic shift
• New virulence factors eg c.diff strain producing more toxin -> increased diarrhoea = increased spread
• Antimicrobial resistance developing eg MRSA

Question 9

Discuss practice factors which can lead to an outbreak

Answer 9

• New practice in social context eg HIV due to changes in sexual practice and injection
• New healthcare practice eg increasing bed occupancy increases c diff spread

Question 10

Discuss some place causes of outbreaks

Answer 10

-Migration moves different strains of pathogen around the world

Question 11

What factors determine the transmissibility of an infection?

Answer 11

• Infectious dose
• Host immunity and response
• Virulence factors
• Mechanism of transmission

Question 12

What pathogen interventions can be put in place to prevent infection?

Answer 12

• Antibacterials to reduce bioburden

- Eradication by destroying habitat

Question 13

What patient interventions can be put in place to prevent infection?

Answer 13

• Improved health via housing and sanitation

- Immunity via vaccinations and herd immunity

Question 14

What practice interventions can be put in place to prevent infection?

Answer 14

• Promote health behaviour ie healthy eating, exercise, safe sex, food prep etc
• PPE for HCP

Question 15

What place interventions can be put in place to prevent infection?

Answer 15

• Isolation rooms

- Environmental engineering -> safe water, air etc

Question 16

What are the dangers with herd immunity?

Answer 16

-If not enough people are vaccinated then may just delay the age of onset of a particular infection which can increase the consequence severity eg polio in children doesnt develop to myelitis but in adults it does

Question 17

What are the consequences of poor infection control?

Answer 17

• Decrease exposure to pathogen can decrease immunity and thus overall the population has an increased susceptibility
• Delay age of onset

Question 18

What are the consequences of antimicrobial resistance?

Answer 18

• Treatment failure
• Economic burden
• Prophylaxis failure
• Increased incidence of death/illness

Question 19

What is MDR defined as?

Answer 19

-Resistant to one agent in 3 or more classes of antimicrobiald

Question 20

What is XDR defined as?

Answer 20

-Resistant to at least one agent in all but two or less classes

Question 21

What is antimicrobial stewardship?

Answer 21

-Interventions designed to improve and measure appropriate use of antibiotics whilst optimising clinical outcomes

Question 22

What are the benefits of antimicrobial stweardship?

Answer 22

• Decreased resistance to drugs
• Decreased cost of healthcare
• Minimise toxicity and ADRs due to shortened course

Question 23

What are the three groups of antimicrobial stewardship interventions?

Answer 23

• Persuasive (education)
• Restrictive (formulary restriction)
• Structural (rapid lab tests)

Question 24

What is a disadvantage of antimicrobial stewardship?

Answer 24

-Potential for readmission of patient as infection has not cleared

Question 25

What is endemic disease?

Answer 25

-Usual background rate

Question 26

Give an example of an infection which is not communicable between humans

Answer 26

-Legionella pneumophilia