Microbial pathogenesis

Question 1

Give examples of the three types of Eukaryotic pathogens

Answer 1

Fungi: tricophyton
Protizoa: Plasmodium spp
Helmiths: hook wormsG

Question 2

Give an example of a bacteria and a virus

Answer 2

Bacteria: anthrax
Virus: influenza

Question 3

Name kosh’s postulate

Answer 3

The guidlines to prove specific disease casuing specific causes specific symptoms
- All carriers of the bacteria must exspress the disease
- Bacteria must be cultured
- Bacteria must then cause same disease in new host

Question 4

What are 2 exceptions to kosh’s postulate

Answer 4

Bacteria which cannot be cultured
Pathogens in healthy individuals

Question 5

Outline the steps in microbial pathogenesis

Answer 5

Exsposure
Adhesion
Invasion of tissues
Colonization and growth
- toxicity = toxisity within the same tissue
- Invasivness = migrate to a new location
Disease causes tissue damage

Question 6

Examples of virulance factors at each stage of micrboial pathogensis

Answer 6

Adhesion - Fimbre to adhere to surface
Invasion of tissue - Motility via flagella - internalin located proteins
Colonisation
- nutriance: siderophores
- Protection: capsule
Disease
- endotoxins
- exotoxins

Question 7

What in an endotoxin

Answer 7

• Natural part of gram negative bacteria lipopolysacharides
• released when the bacteria dies
• causes an over reactive immune reponse
• Cuases: fever, inflamation, shock,, blood clotting

Question 8

What are the classes of exotoxins and what are they

Answer 8

Exotoxins are proteins released into the medium by living bacteria

Cytotoxins - Infect and damage cells
Neurotoxins - damage neural tissues
Entrotoxins - damage gut health and tissues