QuestionSBA
QuestionChoice
Point mutations are single changes in the amino acid sequence of proteins through mutation. These changes are gradual over time, and would not cause influenza pandemics. It is important to remember that RNA viruses have a much higher error rate than DNA viruses because RNA polymerase has no proofreading activity.
TIP: you can remember R for rapid.
10004748
c
Point mutation
QuestionChoice
Salicylic acid is the receptor on the host cell to which the influenza virus haemagglutinin (HA) protein binds to facilitate cellular entry. Mutations in salicylic acid proteins would not lead to influenza pandemics and would not require annual revaccination.
10004749
d
Salicylic acid mutation
QuestionChoice
Antigenic drift is the natural evolution of viral strains due to selective pressure acting on point mutations. As the name suggests, this process is rather slow occurring, and would not produce a new strain of virus quickly to become a pandemic.
10004747
b
Antigenic drift
QuestionChoice
Mutations in the influenza haemagglutinin (HA) protein lead to the process of antigenic drift. Antigenic drift is the natural evolution of viral strains due to selective pressure acting on point mutations. These mutations can occur in proteins such as haemagglutinin (HA) which bind to host salicylic acid receptors and facilitate viral entry.
10004750
e
Haemagglutinin mutation
QuestionChoice
Viral genetic diversity can occur in numerous ways. Antigenic shift is the process by which two or more strains of the influenza virus recombine to produce a new, often more virulent subtype. This is the reason why the World Health Organisation predicts which strains of influenza will be virulent in the coming winter, and initiate target-group-specific annual vaccination campaigns.
10004746
a
Antigenic shift
Concept
Chapter
2693
4327
Influenza
Topic
194
Infectious Diseases
13496
A 68-year-old man presents to his GP for his annual influenza vaccine.

Which of the following concepts is the single most likely explanation for why we have an annual influenza vaccination campaign?
a