title: Influenza activity--Northern Hemisphere, 1984.
mesh_terms: D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D009981:Influenza B virus / Q000302:isolation & purification; D007251:Influenza, Human / Q000453:epidemiology*; D007564:Japan; D014300:Trinidad and Tobago; D006113:United Kingdom; D014481:United States