MOD 5

Question 1

What type of genome does Influenza A have?

Answer 1

-RNA segments

Question 2

How many proteins does Influenza A encode?

Answer 2

10 viral proteins

Question 3

What does Haemagglutinin (HA) bind to?

Answer 3

Sialic acids

Question 4

What triggers HA-mediated fusion?

Answer 4

Low pH

Question 5

What is the function of Neuraminidase (NA)?

Answer 5

Cleaves sialic acids to allow virus release

Question 6

What ion channel protein prevents new HA fusion in the Golgi?

Answer 6

M2 protein

Question 7

What does NS1 protein do?

Answer 7

Antagonizes host antiviral response

Question 8

What is antigenic shift in influenza?

Answer 8

Reassortment of genome segments between two strains

Question 9

What does antigenic drift refer to?

Answer 9

Accumulation of mutations due to lack of proofreading by RdRp

Question 10

What makes a virus pandemic-capable?

Answer 10

Novel, transmissible, and no pre-existing immunity

Question 11

What are severe influenza complications?

Answer 11

Epithelial damage, cytokine storm, secondary bacterial infections

Question 12

How is influenza named?

Answer 12

(Genus)/(host)/(location)/(isolation number)/(year)

Question 13

What must happen to HA0 for infectivity?

Answer 13

It must be cleaved into HA1 and HA2

Question 14

What determines which proteases can cleave HA?

Answer 14

The HA cleavage site (HACS) amino acid sequence

Question 15

What distinguishes LPAI from HPAI?

Answer 15

LPAI has monobasic HACS; HPAI has polybasic HACS

Question 16

What determines RSV-A vs RSV-B?

Answer 16

Antigenic variation in the G protein

Question 17

What type of genome does RSV have?

Answer 17

-ssRNA

Question 18

How many proteins does RSV encode?

Answer 18

11 proteins from 10 genes

Question 19

What is a key reason RSV prevents strong immunity?

Answer 19

It modulates the immune response

Question 20

What is a hallmark of RSV acute disease?

Answer 20

Lower respiratory tract infection causing airway obstruction

Question 21

What immune cells worsen RSV pathology?

Answer 21

Eosinophils and neutrophils

Question 22

What chronic condition can RSV contribute to?

Answer 22

Asthma

Question 23

What age group is most at risk for RSV?

Answer 23

Infants and young children

Question 24

Why did the first RSV vaccine fail?

Answer 24

Induced non-neutralizing antibodies and Th2-biased response

Question 25

What does Palivizumab target?

Answer 25

F protein of RSV

Question 26

What limits Palivizumab's use?

Answer 26

High cost and limited to high-risk infants

Question 27

What is special about Nirsevimab?

Answer 27

Highly neutralizing; 70-day half-life

Question 28

What do fusion inhibitors for RSV target?

Answer 28

Viral binding, fusion, or entry

Question 29

What does Ziresovir target?

Answer 29

F protein

Question 30

What does Ribavirin do?

Answer 30

Nucleoside analog that interrupts RNA replication

Question 31

What does EDP-938 target?

Answer 31

N protein

Question 32

What does EDP-323 target?

Answer 32

L protein

Question 33

What type of virus is SARS-CoV-2?

Answer 33

+ssRNA

Question 34

What helped COVID-19 spillover from animals?

Answer 34

High animal density at wet markets

Question 35

How is SARS-CoV-2 transmitted?

Answer 35

Aerosols, droplets, fomites

Question 36

What is the basic reproduction number (R0) of COVID-19?

Answer 36

~2.5

Question 37

What reduces COVID-19 transmission?

Answer 37

Mask-wearing

Question 38

What is Nirmatrelvir?

Answer 38

A protease inhibitor

Question 39

What is Ritonavir used for in COVID-19 treatment?

Answer 39

Increases Nirmatrelvir concentration

Question 40

What is the efficacy of Nirmatrelvir + Ritonavir?

Answer 40

89% reduction in hospitalization and death

Question 41

What enzyme copies the genome in COVID-19?

Answer 41

RdRp (RNA-dependent RNA polymerase)

Question 42

What is the purpose of discontinuous transcription?

Answer 42

To transcribe short RNAs for protein translation

Question 43

What are four treatment strategies under investigation for Long COVID?

Answer 43

Antivirals (EBV), microbiota replacement, autoimmune therapies, anti-clotting therapies

Question 44

What causes antigenic shift in influenza?

Answer 44

Reassortment of RNA segments when a cell is infected with two different IAV strains

Question 45

What is the result of antigenic shift?

Answer 45

Creation of a novel virus strain → pandemics

Question 46

What causes antigenic drift in influenza?

Answer 46

Accumulation of point mutations due to error-prone RdRp

Question 47

Why does antigenic drift occur in IAV?

Answer 47

Because RdRp lacks proofreading ability

Question 48

What are the main outcomes of acute RSV infection?

Answer 48

Pneumonia, ARDS, need for respiratory support

Question 49

What causes airway obstruction in RSV?

Answer 49

Virus-induced epithelial death and immune cell recruitment

Question 50

What immune cells are recruited in RSV that contribute to pathology?

Answer 50

Eosinophils and neutrophils

Question 51

How does RSV affect airway neurons chronically?

Answer 51

Upregulates nerve growth factor → hyper-responsiveness

Question 52

What long-term condition is associated with unresolved lung injury from RSV?

Answer 52

Asthma

Question 53

Who is most at risk of RSV-related death globally?

Answer 53

Infants and children in lower-middle-income countries

Question 54

What population is at risk in high-income countries?

Answer 54

Older adults with comorbidities

Question 55

By what age has nearly everyone been infected with RSV?

Answer 55

Age 3

Question 56

What percentage of RSV-related deaths occur in lower-middle-income countries?

Answer 56

0.97

Question 57

What was the first RSV vaccine composed of?

Answer 57

Formalin-inactivated virus with alum adjuvant

Question 58

Why did the formalin-inactivated RSV vaccine fail?

Answer 58

It locked F protein in post-fusion state and induced non-neutralizing Th2 response

Question 59

What type of immune response was triggered by the failed RSV vaccine?

Answer 59

Allergy-like Th2 response

Question 60

What was the consequence of the failed RSV vaccine in children?

Answer 60

Enhanced respiratory disease with high RSV load and immunopathology