Healthcare associated infections

Question 1

Define HAI

Answer 1

Infections not present or in the pre symptomatic phase at the time of admission to hospital
which arise >48 hours after admission or within 48 hours of discharge

Question 2

4 possible outcomes of HAI

Answer 2

litigation
increased hospital stay, pain, discomfort, permanent disability and death
increased cost
loss of public confidence and decreased staff morale

Question 3

6 most common sites of HAI

Answer 3

UTI 
respiratory tract infections 
skin and soft tissue infections 
GI infections 
bloodstream infections
surgical site infection

Question 4

How many different species of bacteria have been isolated from the human stool?

Answer 4

over 500

Question 5

What percentage of the population is colonised with staph aureus and where is it found in humans?

Answer 5

30%

in their nose

Question 6

Most people colonised with staph aureus is MRSA or MSSA?

Answer 6

MSSA

Question 7

List 4 ways the same strain colonising can cause infection - examples

Answer 7

break in the skin eg surgical site infection
vascular device eg CVC
catheter associated UTI
ventilator associated pneumonia

Question 8

5 microbial factors tipping the balance towards infection- increased…

Answer 8

virulence 
transmissibility 
ability to evade hosts immune defences 
resistance 
survival ability

Question 9

List some host factors tipping the balance towards infection

Answer 9

break in the skin 
immunosuppression 
other drugs eg PPI 
devices eg catheter 
overcrowding 
age

Question 10

3 parts of the chain of infection

Answer 10

source of microbe (endogenous or exogenous)
transmission
host

Question 11

4 means of transmission and an example of a microbe transmitted this way

Answer 11

faecal oral - c diff
direct contact - staph aureus
respiratory/droplet - Neisseria meningitidis, TB
penetrating injury - blood borne viruses

Question 12

List some ways to break the chain of infection

Answer 12

appropriate PPE 
SIPCs
risk awareness 
closure of wards 
vaccination
hand hygiene

Question 13

Define cleaning

Answer 13

physical removal of organic material and decrease in microbial load

Question 14

Define disinfection

Answer 14

Large reduction in microbe numbers - spores may remain

Question 15

Define sterilisation

Answer 15

Removal or destruction of ALL microbes and spores

Question 16

Give an example of a low risk piece of equipment and how to decontaminate it

Answer 16

stethoscope - intact skin contact

cleaning compatible with manufacturers instructions

Question 17

Give an example of a medium risk piece of equipment and how to decontaminate it

Answer 17

mucous membrane - endoscope

disinfect or sterilise as appropriate

Question 18

Give an example of a high risk piece of equipment and how to decontaminate it

Answer 18

surgical instruments

sterilisation

Question 19

Explain the concept of cleaning

Answer 19

manufacturers instructions
detergent and water
drying
essential prior to disinfection and sterilisation

Question 20

2 methods of disinfection

Answer 20

heat

chemicals

Question 21

Heat - disinfection

Answer 21

pasteurisation or boiling

Question 22

Heat - chemical

Answer 22

vary in organism range and must be equipment compatible

eg alcohol, Hydrogen peroxide

Question 23

4 ways to sterilise

Answer 23

steam under pressure - autoclave
hot air oven
gas
ionising radiation

Question 24

Define outbreak

Answer 24

2or more cases of an infection linked in time and place

Question 25

What is the first purpose of IPC?

Answer 25

prevent individual infections and outbreaks

Question 26

What is the purpose of surveillance?

Answer 26

detect and identify a possible outbreak at the earliest opportunity

Question 27

What must be done to confirm an outbreak?

Answer 27

typing

Question 28

5 typing methods

Answer 28

``` antiobiogram - antibiotic sensitivity pattern phage typing serotyping pyocin typing molecular typing ```

Question 29

6 outbreak control measures

Answer 29

``` single room isolation ward closure staff exclusion cohort cases reinforce PIC measures staff decolonisation ```

Question 30

Clinical characteristics of C diff

Answer 30

diarrhoea faeces have characteristic odour abdominal pain, pyrexia, increased WCC pseudomembranous colitis

Question 31

Epidemiology of c. diff colonisation

Answer 31

2% population increases with age 30% elderly

Question 32

Do toxin negative strains of c.diff cause disease?

Answer 32

no

Question 33

What makes you more susceptible to c.diff infection?

Answer 33

imbalance in gut flora elderly antibiotics

Question 34

What needs to be present for a c.diff diagnosis?

Answer 34

diarrhoea

Question 35

First thing to do in c.diff infection

Answer 35

stop antibiotics predisposing if possible

Question 36

Symptomatic treatment of c.diff

Answer 36

oral metronidazole oral Vancomycin if severe oral fidaxomicin if 2nd episode

Question 37

4 C antibiotics

Answer 37

cephalosporins co-amoxiclav clindamycin ciprofloxacin