The Pathogenesis of Infectious Disease

Question 1

6 steps of infection

Answer 1

attachment and entry
spread
multiplication
countering host defences
shedding (host exit)
host damage

Question 2

2 types of airborne transmission

Answer 2

droplets- larger, cannot be inhaled, fall to the ground
aerosols- can be inhaled directly, tend to dissipate but spread further

Question 3

4 transmission routes

Answer 3

airborne- aerosol or droplet
faecal oral
via animal bite
sexual, or other contact

Question 4

aerosol pathogen

Answer 4

TB

Question 5

faecal oral pathogen

Answer 5

polio

Question 6

TB entry mechanism

Answer 6

macrophage target, CR3 receptors

Question 7

polio target

Answer 7

epithelial or neural cell- CD155 receptor

Question 8

example of ‘hostile environment’ host defence mechanisms

Answer 8

low pH in the vagina and stomach, high temp, nutrient sequestering

Question 9

innate immune system

Answer 9

detects elements which do not exist in the host, e.g. phagocytosis

Question 10

adaptive immune system

Answer 10

development of specific targets for specific pathogens, requires a high diversity of low-number cells such as T and B cells