Lecture 8

Question 1

Which Influenza type usually causes a more severe illness, A or B?

Answer 1

A

Question 2

Influenza virus envelope contains…

Answer 2

• 2 surface glycoproteins (HA and NA)
• M2 ion channel protein

Question 3

Influenza ribonucleoprotein complex

Answer 3

Viral RNA segment associated with the nucleoprotein and 3 polymerase proteins (PA, PB1, PB2)

Question 4

What protein is associated with both the ribonucleoprotein and the viral envelope?

Answer 4

Matrix (M1) protein

Question 5

Influenza virus is a member of the __ family of __ viruses

Answer 5

Orthomyxoviridae family of RNA viruses

Question 6

Influenza virus is classified as type A, B or C based on…

Answer 6

antigen differences in NP and M1

Question 7

Influenza A virus further subtyped based on…

Answer 7

the antigenicity of HA and NA

Question 8

2 Influenza B lineages

Answer 8

Victoria and Yamagata

Question 9

Currently 16 HA and 9 NA subtypes, all of which are maintained in…

Answer 9

aquatic bird populations

Question 10

The genome of Influenza A consists of 8 __ molecules, encoding __ proteins

Answer 10

8 single-stranded negative sense RNA molecules, encoding 11 proteins

Question 11

All current Influenza vaccines contain…

Answer 11

H1N1 (group 1) and H3N2 (group 2) strains, B/Yamagata and B/Victoria lineages

Question 12

Influenza A infects __ in humans

Answer 12

URT

Question 13

What is antigenic shift?

Answer 13

Gene swapping in cells simultaneously co-infected with 2 different Influenza viruses e.g. 1957 pandemic when a H1N1 virus reassorted with a H2N2 virus

Question 14

Antigenic shift leads to…

Answer 14

the formation of new strains and, therefore, epidemics

Question 15

Antigenic shift is found in…

Answer 15

Influenza A only

Question 16

What is antigenic drift?

Answer 16

Point mutations leading to small change to protein coat (virus under pressure from antibody to HA)

Question 17

Antigenic drift is found in…

Answer 17

both Influenza A and B

Question 18

Antigenic drift causes __

Answer 18

seasonal variation

Question 19

How are Influenza vaccines currently produced?

Answer 19

from genetically reassorted viruses with required H and N types adapted to growth in eggs

Question 20

Split virion trivalent Influenza vaccines

Answer 20

Influvac, Fluarix

Question 21

How many µg of HA is taken from each strain and incorporated into the vaccine?

Answer 21

15

Question 22

Live attenuated Influenza vaccine

Answer 22

FluMist Quadrivalent

Question 23

Why is FluMist delivered intranasally?

Answer 23

better mucosal responses, site of infection

Question 24

FluMist induces…

Answer 24

T cell and antibody responses

Question 25

What type of vaccine is Fluad?

Answer 25

- inactivated - adjuvanted (Squalene/MF59) - licensed for use in the elderly

Question 26

Most mutations are seen in the __ region

Answer 26

HA head region

Question 27

Approaches to making a universal Influenza vaccine

Answer 27

- Understand breadth of B cell responses - Better adjuvants & routes to broaden immunity - Induce broadly neutralising Abs (e.g. identify conserved HA epitopes in stalk)

Question 28

Do recombinant viral vectors induce/boost T cell responses to the encoded antigen?

Answer 28

Yes

Question 29

2 examples of recombinant viral vectors

Answer 29

MVA (Modified Vaccinia virus Ankara) Adenovirus