title: [Influenza].
authors: M
authors: M
authors: Kaji
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D009980:Influenza A virus; D007251:Influenza, Human / Q000150:complications / Q000453:epidemiology* / Q000517:prevention & control; D007564:Japan / Q000453:epidemiology; D008171:Lung Diseases / Q000150:complications; D008875:Middle Aged; D012307:Risk Factors