pathogenicity and virulence

Question 1

habitat of saprophytic bact

Answer 1

environment, water, soil - recycling

mucus membranes, skin of animals and humans

Question 2

pathogenic bact habitat

Answer 2

mainly animals, humans
environment
replication mainly in infected host

Question 3

saprophytes host-mo interaction

Answer 3

symbiosis/mutualism

Question 4

example of symbiosis

Answer 4

• bact of caecum of rabbit and horses, rumen of ruminants

- natural bacteriota

Question 5

pathogenic bact host-mo interaction

Answer 5

parasitism

predator prey interactio

Question 6

example of parasitism

Answer 6

fac pathogens - predisposing factors are needed for disease production

Question 7

example of predator prey interactions

Answer 7

obligate pathogens

Question 8

sources of infection

Answer 8

environment
carrier animals
through mouth, nose, eyes
genitals
skin
faecal-oral route

Question 9

infection host spectrum

Answer 9

euryxenic

stenoxenic

Question 10

examples of euryxenic host spectrum

Answer 10

erysipelothrix rhusiopathiae

bacillus anthracis

Question 11

examples of stenoxenic host spectrum

Answer 11

actinobacillus pleuropneumoniae, salmonella typhi

Question 12

whats pathogenicity

Answer 12

ability of a microbe to damage a host

Question 13

is pathogenicity quantitative

Answer 13

no qualitative

Question 14

whats virulence

Answer 14

degree of pathogenicity

Question 15

is virulence quantitative

Answer 15

yes

Question 16

whats virulence connected to

Answer 16

certain bact isolate

Question 17

whats pathogenicity connected to

Answer 17

one bact species - one host species

Question 18

name three virulence variants

Answer 18

virulent
moderately virulent
avirulent

Question 19

when can we measure virulence

Answer 19

only in animal trials

only in target animal species

Question 20

validity of virulence

Answer 20

only in relation to certain strain and certain host species

Question 21

whats MLD

Answer 21

min lethal dose

Question 22

what MID

Answer 22

min infective dose

Question 23

can virulence change

Answer 23

yes

Question 24

causes for incr of virulence

Answer 24

passage in the host species

recombination - induced or spontaneous

Question 25

causes for decr of virulence

Answer 25

mutation, spontaneous, passage - maintained in lab, culture at suboptimal temp, culture on suboptimal media, in presence of ABs, dyes, chemicals

Question 26

two types of virulence factors

Answer 26

non toxic

toxic

Question 27

non toxic virulence factors

Answer 27

cell wall associated factors, extracellular enzymes

Question 28

toxic virulence factors

Answer 28

exotoxins, endotoxins

Question 29

types of capsule virulence factors

Answer 29

d glutamic acid polypeptide
hyaluronic acid
polysaccharides
inhibits phagocytosis, protect bacterium
better replication, more tissue damage

Question 30

adhesins virulence factors

Answer 30

fimbria

surface proteins

Question 31

antiphagocytic materials virulence factors

Answer 31

prevent fusion of phagosome and lysosome
lipid complexes
mycolic acid, waxes

Question 32

extracellular enzymes

Answer 32

coagulase
fibrinolysin
hyaluronidase
collagenase
lipase
lecitinase
deoxyribonuclease
urease
leucocidins
haemolysins

Question 33

exotoxins

Answer 33

cytoxins

gr+ and Gr-

Question 34

endotoxins

Answer 34

Gr- bact

Question 35

what are exotoxins made up of

Answer 35

protein

Question 36

what are endotoxins made up of

Answer 36

LPS

Question 37

how are exotoxins released

Answer 37

excreted

Question 38

how are endotoxins released

Answer 38

cell lysis

Question 39

list things that influence disease of the host

Answer 39

pathogen
virulence
amount of acquired bacterium
route of infection
resistance of host