Module 4

Question 1

infection

Answer 1

when microorganisms invade host tissue and multiply

Question 2

subclinical infection

Answer 2

no symptoms but immune response had happened

Question 3

localised infection

Answer 3

confined to one area of body

Question 4

systemic infcetion

Answer 4

spreads to other organ systems

Question 5

pathogen

Answer 5

microorganism capable of causing disease

Question 6

pathogenesis

Answer 6

process in which disease arises

Question 7

pathogenicity

Answer 7

measure of ability of pathogen to cause disease

Question 8

pathogenic determinant

Answer 8

feature that influences how well it can cause disease

Question 9

endemic

Answer 9

disease always present in population

Question 10

epidemic

Answer 10

sudden rapid rise in disease incidence

Question 11

pandemic

Answer 11

global epidemic

Question 12

outbreak

Answer 12

high number of infections where no cases occured in the past

Question 13

Define Koch’s postulates

Answer 13

1. suspected pathogen must be present in all cases of disease and absent from healthy animal
2. pathogen must be grown in pure culture
3. cells from pure culture must cause disease in healthy animal
4. pathogen must be deisolated and shown to be the same as the original

Question 14

What are the progression stages of an infectious disease

Answer 14

incubation period, prodromal phase (minimal symptoms), invasive phase, acme (highest point), decline phase and convalescence period

Question 15

Differences between gram positive and gram negative

Answer 15

Positive have thick layer of peptidoglycan cell wall and negative have thin layer

Question 16

Stages of bacterial reproduction

Answer 16

lag phase, exponential/ log, stationary and death

Question 17

enveloped virus

Answer 17

entire virus is surrounded by outer membrane derived from host cells

Question 18

6 viral lifestyle steps?

Answer 18

1. attachment
2. penetration
3. uncoating
4. replication
5. assembly

Question 19

Tropism + 3 types

Answer 19

virus target specific cells

cellular, tissue and host

Question 20

where do RNA Viruses replicate

Answer 20

cytoplasm

Question 21

where do DNA viruses replicate

Answer 21

nucleus

Question 22

Describe the infection consequences of viral infection

Answer 22

• acute infection - infection cleares
• productive chronic infection - persistent infection for a long time
• non-productive latent infection - virus remains present but not active, may appear later
• transformation - transforms host cell into tumour or cancer

Question 23

pathophysiology

Answer 23

damage to cells due to virus replication and host response

Question 24

2 DNA viruses

Answer 24

DNA - Pappilomavirus and Herpesvirus

Question 25

2 RNA viruses

Answer 25

RNA - Coronavirus/ Influenza and Flavivirus

Question 26

3 major fungi groups

Answer 26

macroscopic - mushrooms multicellular filamentous moulds singe cell yeasts

Question 27

3 pathogenic fungi types

Answer 27

filamentous, yeast, dimorphic

Question 28

basic fungal structure and function

Answer 28

thick carbohydrate wall - protects from environment - acquisition of nutrients - cell recognition and mating

Question 29

3 fungi structure types

Answer 29

moulds, yeast and dimorphic

Question 30

3 types of fungal infections

Answer 30

superficial mycoses - ringworm and thrush subcutaneous mycoses - madura foot systemic mycoses - histoplasmosis

Question 31

3 parasite types and examples

Answer 31

helminths - pinworm protozoa - Plasmodium causing malaria arthropod - ticks and fleas

Question 32

Describe how healthcare environment contributes to incidence of infectious disease (3)

Answer 32

- older and vulnerable hosts - multiple routes of infection - use of antimicrobials - constant pressure is selective for resistant organisms

Question 33

Describe what is meant by MRSA, its key virulence factors and pathophysiology

Answer 33

methicillin- resistant staphlyococcus aureus resistant to many first line antibiotics and beta-lactam antibiotics.

Question 34

Bacterial HCAI's

Answer 34

C. Diff - found in feces of babies and in disturbed gut bacteria in adults UTI's - mostly caused by e.coli and can lead to kidney infection

Question 35

Viral HCAI's

Answer 35

RSV- lower respiratory infection in babies and is transmitted via objects Rotavirus-neonatal diarrhoea and its transmitted faecal- oral

Question 36

Antibiotic targets (4)

Answer 36

1. cell metabolism 2. cell wall synthesis 3. nucleic acid synthesis 4. cell membrane function

Question 37

Describe bacterial antibiotic resistance mechanisms

Answer 37

1. production of enzymes- destroys the antibiotics 2. alteration of bacterial binding sites- antibiotics cant get in cause binding site has changed 3. change in membrane permeability - outer membrane protein block 4. alternate pathways - drug efflux pumps and targeting overproduction

Question 38

Describe what human practices can lead to antibiotic resistance and what can be done to prevent it

Answer 38

- low dosage - poor adherence - poor prescribing - viral infection - use of broad- spectrum antibiotics

Question 39

Routes of infection

Answer 39

- airborne - direct or indirect contact - faecal oral - vector borne - sexual

Question 40

sterilisation + eg

Answer 40

killing of all viable organisms | eg. Heat or irridation

Question 41

disinfection + eg

Answer 41

killing of most viable organisms | eg. chemical disinfectant or filtration

Question 42

infection controls management

Answer 42

hand hygeine ppe contact precautions cough etiquete

Question 43

what makes host susceptible

Answer 43

age, immunocompromised, pregnant, trauma

Question 44

Consequences of hospital infections

Answer 44

illness or death prolonged stay in hospital patient becomes source of infection

Question 45

prevention of hospital infections

Answer 45

exclude sources of infection from environment interrupt transmission from source to host increase host resistance

Question 46

patient management of infection

Answer 46

minimise operation length adequate wound drainage preventing sores

Question 47

shape of 'staphe' bacteria

Answer 47

grapes

Question 48

shape of 'coccus' bacteria

Answer 48

round berry

Question 49

aurus

Answer 49

gold

Question 50

shape of 'bacci' bactera

Answer 50

ros shaped

Question 51

classification of a virus

Answer 51

type of nucleic acid arrangement of nucleic acid structure of virus particle symmetry of capsid

Question 52

pathogenic consequences of viral infection

Answer 52

acute infection productive chronic non productive latent transformation

Question 53

types of antimicrobials

Answer 53

anti parasitic anti fungal anti viral anti bacterial - antibiotics

Question 54

gene transfer

Answer 54

transformation transduction conjugation transponsons