respiratory viruses

Question 1

name some respiratory diseases caused by virus

Answer 1

common old, influenza like illness, pneumonia, pharyngitis, croup

Question 2

define a respiratory virus

Answer 2

virus whose main domain or clinical presentation is in the respiratory tract, note some virus are just spread by respiratory tract

Question 3

describe the respiratory epithelium

Answer 3

ciliated pseudostratified columnar epithelium

Question 4

describe oral mucosal epithelium

Answer 4

stratified squamous epithelium

Question 5

why are respiratory virus able to act in the respiratory tract

Answer 5

because they have specific viral receptors for this area of the body. along the respiratory tract the requirements differ so some virus could be lower or higher. this is viral tropism

Question 6

what is incubation period of flu

Answer 6

1-4 days

Question 7

name upper respiratory infection syndromes

Answer 7

common cold, pharyngitis, laryngitis,

Question 8

name lower respiratory tract infections

Answer 8

pneumonia, bronchiolitis,

Question 9

what is most likely cause of bronchiolitis

Answer 9

respiratory synctical virus rsv

Question 10

what is most common cause of common cold

Answer 10

rhinovirus and coronaviruses

Question 11

what is the most common cause of croup

Answer 11

parainfluenza viruses

Question 12

what is the most common cause of influenzas like illness

Answer 12

parainfluenza viruses and adenoviruses

Question 13

what three conditions are needed for transmission of infective disease

Answer 13

risk (sufficient viral load)
a susceptible individual( immune deficient)

and effective contact between them

(targeting this factors can reduce risk of spread)

Question 14

what type of droplets are RSV and common colds transmitted in

Answer 14

Large droplets

Question 15

what type of droplets or aerosols are measles, chickenpox, influenza, mumps, rubella and sars transmitted in

Answer 15

small droplets noe not all are respiratory viruses

Question 16

how has knowledge of infection transmission impacted clinics

Answer 16

staff ppe, bed spacing, air change regulations, isolation facilities, post exp prophylaxis

Question 17

describe influenza virus structure

Answer 17

haemaglutin on surface, neuroaminidases and m2 ion channels , on inside rnp

Question 18

influenza is a zoonosis what is the specific name of the virus that causes it

Answer 18

orthomyxovirus

Question 19

what are the 3 genera in the orthomyoxovirus family that cause flu

Answer 19

abc

Question 20

describe the genome of orthomoxyviruses

Answer 20

single strand rna negative genome, lipid envelope

Question 21

what are the two surface glycoproteins on orthomyxoviruses

Answer 21

hemagglutin and neuraminidase

Question 22

what are the main antigenic determinants of influenza

Answer 22

hemagglutin(HA) and neuraminidase (NA)

Question 23

what does HA antigen do

Answer 23

its determines cell tropism and binds to the sialic acid residues on cell surface

Question 24

what does NA do as an antigen

Answer 24

it catalyses cleavage of glyosidic linkages to sialic bonds allowing exit of new virions from the cell it is a target for anti flu therapy

Question 25

which animal acts as the reservoir for flu

Answer 25

wild birds are reservoir for all hn types of influenza a

Question 26

what are the influenza a subtypes based on

Answer 26

h and n genes and their variants

Question 27

how are pigs and other mammals relevant to flu

Answer 27

they can act as shuttle hosts

Question 28

so how can influenza be spread

Answer 28

coughing and sneezing, large droplets, direct contact with secretions

Question 29

when can influenza put you at risk of death

Answer 29

Viral pneumonitis • Secondary bacterial pneumonia, that sneaks in when immune system is “distracted” Pneumococcus & Staphylococcus aureus