The incidence of A2-Hong Kong infections in blood donors during the winter of 1970.
D001315:Australia; D001782:Blood Donors; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007252:Influenza Vaccines; D007251:Influenza, Human / Q000175:diagnosis / Q000453:epidemiology*; D011795:Surveys and Questionnaires
D007252:Influenza Vaccines