M4 Sources of Microorganisms Flashcards Preview

Microbiology 2 > M4 Sources of Microorganisms > Flashcards

Flashcards in M4 Sources of Microorganisms Deck (44)
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1
Q

what s the sequence of events for pathogenesis

A

adhere/colonise and invade
evade host defence
multiply/compete its life cycle
exit host

2
Q

what are some common bacteria use humans as reservoir

A
TB 
Diphtheria 
Hep A & B 
Influenza 
Measles
3
Q

what are some common bacteria use animals as reservoir

A

Zoonoses
accidental infection of man
may involve vector
plague

4
Q

what are some sources of environment for bacteria

A

soil nd water
contaminated sewage
opportunistic pathogens

5
Q

what are some bacteria that use the environment as a resveoir

A

clostridium tetani

legionella

6
Q

what is an animate nd inanimate source

A

animate - animal

inanimate - environment

7
Q

what is human period of infectivity

A

casual hours
acute days
transient weeks
chronic months +

8
Q

what are the carrier states

A

active
convalescent
healthy
incubator

9
Q

what is the active state

A

overt clinical presentation

10
Q

what is the convalescent state

A

recovering bit still carrier

11
Q

what is a healthy state

A

no overt signs of illness

12
Q

what is the incubator state

A

maintaining large numbers of pathogens prior to illness

13
Q

what are the means exiting a host

A

natural or artificial

14
Q

what is the natural exit way

A

sneezing, shedding

15
Q

what sit he artificial exit way

A

blood, saliva, aerosols (drill)

16
Q

what are some means of spreading to new host

A

direct/indircet contact
air bourne
vector bourne

17
Q

what are the types of direct contact spread

A

vertical - child to mum

horizontal - cough

18
Q

what are the types of indirect contact speed

A

format

19
Q

what is an air bourne spread

A

droplets

aerosols

20
Q

what is vector bourne spread

A

insects

21
Q

how can microbes escape body

A
tears 
nasal sec 
saliva
blood
resp fluid
contact with skin 
breast milk 
faeces
semen 
urine
22
Q

what are some routes of microbial entry

A
ingestion 
inhalation
injection 
across mucous mem
into ear 
transplacental
23
Q

what kind of bac can be ingested

A

salmonella

24
Q

what kind of bac can be inhaled

A

myco TB

25
Q

what kind of bac can be injected

A

Hep b

26
Q

can reservoirs change

A

can vary during the course of a disease

27
Q

what is an exogenous bac

A

infective material derived from outside patients body

28
Q

what is endogenous

A

bac/fungi part of natural microbiota commensal

change in natural flora

29
Q

what are some infections from exogenous bac

A

TB - myco - humans
Pneumonia - legionella - soil/water
Tetanus - clostridium tetani - soil

30
Q

what bac present when burns or wounds

A

s aureus

p aeruginosa

31
Q

what bac present when bowel rupture

A

bacteriodes fraigils

32
Q

when is there a normal presence of foreign body

A

prosthesis
catheters
absence of shedding surface an form of biofilms

33
Q

what are some key points on biofilms

A
multi cellular community 
3D 
interfaces
water channels 
resistant to antimicrobial agents and host defences
34
Q

what si the way a bacteria can go to the incorrect site

A

heatogenuos spread

35
Q

what can suppress immune system

A

cancer therapy
immune suppression
reduced Abs

36
Q

what are some exogenous infections pathogens

A

influenza - destroy line of resp tract

AIDS immune suppression

37
Q

antibiotics can disrupt what microflora

A

natural flora
c albicans
c difficile

38
Q

what are the factors in establishing disease

A

dose of infectious agent
virulence of organisms
seusceptitbitly/ resistance of host

39
Q

give a summary of pathogenesis

A
source microbe 
escape form source
spread to new host
entry into host 
infection of host 
damage to host
40
Q

what is primary sources of dental practice

A

resp trat and muht

secretions saliva and blood

41
Q

what is the secondary source of dental practise

A

surgery equipment

drill mirror

42
Q

what are some challenges faced by pathogenic bac in water

A
low temp
low nutrient 
pH neutral
oxygen available 
resp metab 
free iron available 
adhesins stick to rocks
43
Q

what re some challenges faced by pathogenic bac in humans

A
higher temp 37C 
energy higher
low pH then higher
low or no oxygen
fermentative metab 
iron bound to harm 
adhesions stick to cells 
expo to bile salts
44
Q

what do endogenous microbes do to survive

A

adapt to host and adhered more likely to poise a threat