2.1 The Infection Model

Question 1

Give an example of a virus

Answer 1

HIV

Question 2

Give an example of a bacterium

Answer 2

S. aureus

C. diff

Question 3

What are the two subtypes of parasites?

Answer 3

Protozoa and Helminth (worms)

Question 4

What are the two subtypes of fungi?

Answer 4

Moulds and Yeast

Question 5

List the 5 personal areas that need to be considered about a patient in the infection model

Answer 5

Age
Gender
Physiological state
Pathological state
Social factors

Question 6

With regard to a patient in the infection model, what factors regarding time need to be taken into account?

Answer 6

Relative time- how long exposed

Calendar time- time of year eg. Winter

Question 7

Explain what is meant by contiguous spread of infection and give an example

Answer 7

Harmless bacteria in one commensal get transferred to another area where the bacteria become harmful.
Eg. S. aureus on the skin enter the body via a surgical wound

Question 8

Explain what is meant by the spread of infection by inoculation and give an example

Answer 8

The protective barrier eg. skin is broken by trauma and infection enters the body
Eg. scratched by a stick can lead to tetanus

Question 9

Explain what is meant by the haematogenous spread of infection and give an example

Answer 9

Bacteria in the body spreads to another site via the blood stream
Eg. Squeeze spot on the face, S. aureus enters the blood stream and infects heart valves

Question 10

Explain what is meant by the spread of infection by ingestion and give an example

Answer 10

Ingesting food that is contaminated with faecal remains or other bacteria.
Eg. raw meat, Salmonella

Question 11

Explain what is meant by the spread of infection by inhalation and give an example

Answer 11

Infections particles of a disease are breathed in

Eg. chickenpox bacteria

Question 12

Explain what is meant by the spread of infection by a vector and give an example

Answer 12

The human is infected via another organism

Eg. mosquitos transmit malaria

Question 13

Explain what is meant by vertical transmission of infections and give an example

Answer 13

Infections can be spread from mother to child eg. from breast milk
Eg. HIV

Question 14

How do pathogens cause a response in humans?

Answer 14

Produce toxins

Initiate an immune response

Question 15

List the 3 stages of management that will lead to a diagnosis

Answer 15

History
Examination
Investigation

Question 16

What are the two outcomes of an infection?

Answer 16

Cure -> Death

Question 17

Name the 4 types of pathogens

Answer 17

Bacteria, viruses, parasites and fungi