Influenza: 10.28.2022. IS questions Flashcards
how many strains of influenza are there? what are they?
4: A, B, C, and D
based on the structure of the influenza virus, would you expect it to “survive” for long periods in the environment?
no. because it’s an enveloped virus, it is more susceptible to sanitizers, detergents, and soaps
describe the genome structure of the influenza virus, and comment on the mutation rate of this virus
the influenza A virus genome is segmented. mutations happen frequently enough to make immunity developed to virus strains of previous years less effective
what are the two major antigens of the influenza virus? what are their fancy names?
HA (hemagglutinin) and NA (neuraminidase) antigens
what is the function of HA antigen to the flu virus? where is it found?
hemagglutinin.
receptor binding / attachment. found on the surface of the virion embedded in the membrane
textbook:
- facilitate viral entry by recognizing/attaching to specific receptors on ciliated host epithelial cells
- cause red blood cells to stick together (hemagglutination), which is useful in virus identification
what is the function of NA antigen to the flu virus? where is it found?
release.
found on the surface of the virion.
——-
textbook:
- an enzyme that destroys the receptors that newly formed virions attach to when they leave the cell
- aids the spread of the virus
what is the role of M2 ion channel protein of the influenza virus?
aid viral genome release into cytoplasm
what effect do the different strains of influenza have on humans?
A & B: severe diseases
C: mild diseases
D: no known diseases in humans
what is the structure of influenza virus? (3)
enveloped, single-stranded RNA virus with a segmented genome
what does it mean that the influenza A virus genome is segmented?
viral proteins are encoded on eight different RNA segments rather than being encoded on one long molecule
which H and N subtypes usually spread from person to person?
H1-3
N1-2
