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Flashcards in Respiratory Tract Infections Deck (31)
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1

portals of entry for invading microorganisms in order of importance

1. Respiratory Tract [Upper (URT): Head and Neck and Lower (LRT): Thorax]
2. Gastrointestinal Tract
3.Urogenital Tract
4.Skin [Wounds, Inapparent breaks and cracks, Unbroken Skin]

2

can you die from a respiratory tract infection

no you cannot but you can die from its complications

3

at risk groups for respiratory tract infections

immunocompromised population -- very young and very old

4

can you distinguish between etiological agents on basis of clinical manifestation

no you cannot

5

what is infectious pharyngitis

sore throat

6

for a single syndrome, can you have multiple etiologies

yes you can and vise vera
you can have one etiology causing multiple syndromes depending on strain, where in the body, and other factors

7

what are some features of respiratory tract

temperature differential (lower temp in the RT)
significant air exchange (breathing)
antimicrobial barriers

8

in the respiratory tract, establishment of infection requires?

by-pass barrier defenses & filtering systems
contact with suitable receptor surfaces
evasion of immune response

9

can a majority of microorganism gets passed our natural defenses

no

10

size a particle must be to get passed lower RT

less than 5 microns

11

differences between upper and lower RT

upper (nose to bronchioles): lower temp (33-35oC), normal flora, respiratory epithelium, secretory IgA

lower (bronchioles down): 37oC, sterile, particles less than 5 microns can't pass, nonciliated epithelium, IgA and IgG

12

effects if microorganisms makes it to the lower RT

more severe symptoms

13

purpose of cilia

moves mucus down to the glottis to be discarded

14

what is mucus made up of

mostly water, ions, proteins, glycoproteins, lipid

they all have antimicrobial effects

15

defense of the respiratory system are defeated by

􏰀Smoking
􏰀Endotracheal intubation 􏰀
Pollution
􏰀Suppression of the Cough Reflex
􏰀Predisposing infection
􏰀Disruption of homeostasis (Age, malnutrition, immunosuppression)

16

what are group of agents for infections

1. professional or frank invaders - primary infectors

2. secondary or opportunistic invaders (part of our normal flora)

17

when do secondary invaders act

after professional invaders have created damage, the secondary come in and create further damage

18

primary respiratory infections

influenza and rotavirus

19

how does one get exogenous infections

-inhalation of infectious droplets (talking, sneezing, coughing)
-inhalation of dust, fungal spores
-self-inoculation of eyes, nose, or mouth via droplets on hands

20

what types of droplets remain suspended longer

small droplets
dried droplet nuclei = even longer

21

how can one avoid infections

wearing a p100 mask

22

most common cause of work force absenteeism in north america

respiratory infections

23

can bacteria survive drying

most bacteria can't survive drying -- they need wet surfaces

24

what kills most bacteria and virus

sunlight

25

survival time of the following viruses in dry inanimate surfaces:

coronavirus, RSV, rhinovirus, adenovirus

coronavirus - 3 hours
RSV - 6 hours
rhinovirus - 2 hours to 7 days
adenovirus - 7 days to 3 months

26

viral persistence on dry inanimate surfaces is significant to?

fomite mediated transmission and survival in droplets

27

endogenous infections are due to what

members of the normal flora

28

how does normal flora become endogenous infections

they move to unusual locations (like they don't belong in the RT)

29

why does normal flora relocate to abnormal location

age, preceding infections, smokers

30

things used to diagnose RTIs

age, season, symptoms, in office tests, lab diagnosis