a. Explain how the antibody content of a patient’s sera could be used to predict which strain of influenza predominated during a previous epidemic.
b. Explain the precise way that cross-species influenza infections give rise to new and different strains of virus.
c. Relate this answer to the avian influenza virus and how it could cause a human pandemic.
d. Explain why influenza RNA must enter the cell nucleus during its multiplication cycle, whereas many RNA viruses do not.