Lecture 8 Flashcards
Which Influenza type usually causes a more severe illness, A or B?
A
Influenza virus envelope contains…
- 2 surface glycoproteins (HA and NA)
- M2 ion channel protein
Influenza ribonucleoprotein complex
Viral RNA segment associated with the nucleoprotein and 3 polymerase proteins (PA, PB1, PB2)
What protein is associated with both the ribonucleoprotein and the viral envelope?
Matrix (M1) protein
Influenza virus is a member of the __ family of __ viruses
Orthomyxoviridae family of RNA viruses
Influenza virus is classified as type A, B or C based on…
antigen differences in NP and M1
Influenza A virus further subtyped based on…
the antigenicity of HA and NA
2 Influenza B lineages
Victoria and Yamagata
Currently 16 HA and 9 NA subtypes, all of which are maintained in…
aquatic bird populations
The genome of Influenza A consists of 8 __ molecules, encoding __ proteins
8 single-stranded negative sense RNA molecules, encoding 11 proteins
All current Influenza vaccines contain…
H1N1 (group 1) and H3N2 (group 2) strains, B/Yamagata and B/Victoria lineages
Influenza A infects __ in humans
URT
What is antigenic shift?
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
Antigenic shift leads to…
the formation of new strains and, therefore, epidemics
Antigenic shift is found in…
Influenza A only