Respiratory Viruses

Question 1

most common viral cause of bronchiolitis

Answer 1

RSV( and HMPV)

Question 2

has surface protein, F, that fuses w/cell membrane @ neutral pH

replicates in ciliated epithelial cells lining respiratory tract

Answer 2

parainfluenza virus

Question 2

rhinovirus attaches via_____to target cell

induces the production of ______ and ______ to induce vasodilation and inflammation

Answer 2

rhinovirus attaches via ICAM1 to target cell

induces the prodcution of bradykinin and IL8 to induce vasodilation and inflammation

Question 2

complications of flu?

Answer 2

superinfection

increases risk of s.aureus pneumonia and pneumonia in general

Question 3

flu presentation

Answer 3

FEVER, HA, MYALGIA, MALAISE

+ resp symptoms(cough, sore throat)

+-GI symptoms(NVD)

Question 4

most susceptible population for bronchiolitis?

risk factors?

Answer 4

**neonates/bebes **are most at risk;

any abnormal/birthing complications/defects will predispose the child to bronchiolitis;

Question 4

palivizumab

Answer 4

monoclonal Ab prophylaxis for RSV

give to premies/bebes @ high risk

Question 6

most common viral cause of croup

Answer 6

parainfluenza virus

Question 7

CPE for influenza

Answer 7

kills ciliated epithelium in throat

Question 9

internal ribosome entry sites

Answer 9

regions which ribosomes bind to on **rhinovirus mRNA **to initiate translation

Question 9

why does rhinovirus have nasal specificity

Answer 9

grows better at 33/34C than 37C; colder temps

Question 10

flu season?

Answer 10

winter(october-march)

Question 11

peak season for parainfluenza infections?

Answer 11

FALL OR LATE SPRING

like the common cold…

Question 12

hallmark of croups?

Answer 12

narrowing of subglottic region

steeple sign

Question 13

duration of common cold

peak viral growth?

Answer 13

~a week(5-7 days)

peak growth @ ~day 3

Question 13

presentation of rhinovirus

Answer 13

nasal mucosa ifection: sneezing, rhinitis, nasal obstruction,sore throat

FEVER UNCOMMON

Question 15

describe pathogenesis of RSV

Answer 15

infects nasopharyns(turbinates) then spreads to lower respiratory tract

causes necrosis of bronchiolar epithelium and destroys epithelial cells

inflammation, mucous, cell debris clog bronchioles

Question 16

peak season for rhinovirus

Answer 16

FALL, LATE SPRING

Question 17

Relavent respiratory viruses(transmited via respiratory droplets)

Answer 17

rhinovirus

parainfluenza

influenza

RSV(and HMPV)

Question 18

peak season for bronchiolitis

Answer 18

october-may - Patel

Question 19

most susceptible to flu?

Answer 19

very young and very old

still nasty for anyone

Question 21

most common viral cause of common cold

Answer 21

rhinovirus

Question 23

antigenic drift vs shift for influenza genome

Answer 23

shift is combo of 2 influenza genomes = pandemic

drift is minor changes to genome through mutation as it moves through population

Question 24

describe the genome of influenza

what determines influenza strain?

Answer 24

segmente genome(8 segments); RNA(-)

HA, NA types determine influenza strain

Question 25

describe entry/replication of influenza

Answer 25

• HA binds sialic acid on surface
• Enters in endosome
• endosome acidifies, changing conformation of HA to fuse with endosome membrane;
• M2 dependent uncoating
• RNA heads to nucleus for replication/transcription

Question 26

where does influenza virus replicate w/in the cell?

Answer 26

nucleus

Question 27

2nd leading cause of childhood hospitalizations for acute respiratory infections

Answer 27

croups; parainfluenza

Question 28

most common/suscpetible age for croups

Answer 28

pre-school age; dont see it much after age 6

Question 29

SARS-CoV receptor

MERS-CoV receptor

Answer 29

SARS - ACE2; ciliated epithelium

MERS - DPP4; alveorlar