Influenza Flashcards
Everything about influenza in New Zealand.
What do the H and N in H1/N1 represent?
Surface proteins Hemagglutinin and Neuraminidase.
What does Hemagglutinin do?
The hemagglutinin glycoprotein binds to the monosaccharide sialic acid on host cells
What does Neuraminidase do?
1) remove sialic acid receptors from cells enabling virion liberation, 2) assist virus mobilty through resp tract
What is the name of the Southern Hemisphere vaccine at May 2020?
Afluria Quad
What is the name of the discount Northern Hemisphere vaccine at May 2020?
Influvac Tetra
How many strains are there within the Southern Hemisphere May 2020 vaccine?
Four
Which strains in the Northern and Southern Hemisphere vaccines are identical?
A H1N1 and B H1N1 (Phuket)
Which strains are a close match in the Southern and Northern Hemisphere vaccines?
B/Washington in the Southern is similar to B/Colorado in the Northern
What is the name of the 4th strain in each of the Southern and Northern Hemisphere vaccines?
A/South.Australia/H3N2 in the Southern and A/Kansas/H3N2 in the Northern
What other vaccine can pregnant women get (in T2/3) besides influenza vaccine?
Pertussis
What family do influenza viruses belong to?
Orthomyxoviridae
How many segments do Type A and Type B have vs Type C
Type A & B have 8 RNA negative sense segments, and Type C has 7 negative sense RNA segments.
How can Type A be further subdivided?
By surface glycoproteins H and N.
What are the two most common Type A HN subtypes to infect humans?
H3N2 and H1N1
In A/Duck/Alberta/35/76(H1N1) what do the 35 and 76 represent?
35th strain that was found
1976 is the year it was found
Of Types A, B, and C, what is the order of mutation frequency (most to least)?
A, B, C
Of Types A, B, C, which only infects humans, vs humans and animals?
Type A = animals and humans
Type B = only humans
Type C = humans and pigs
Of Types A, B, and C, what is the incidence of infection frequency, from highest incidence to lowest?
A, B, C
What is genetic drift and how does it influence Type A mutation?
Genetic drift is the random variation of alleles (form of a gene) as generations are replicated.
(younger generations are drifters)
What are two ways that Type A changes and keeps re-infecting humans every year?
- Genetic Drift
2. Antigenic Shift
What is Antigenic Shift?
Antigenic Shift is the reassortment of genes between two strains, likely during co-infection of a single organism.
(shifting house to be with another person who has a pet pig)
Which is the more common form of change in Type A, Genetic Drift, or Antigenic Shift?
Genetic Drift.
How are influenza viruses spread?
Droplets eg cough/sneeze. Touching surfaces eg door handles.
How long do influenza viruses survive on surfaces?
Up to 3 hours.
