Epidemiological studies concerning choice of population for immunoprophylaxis of influenza.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control*; D008875:Middle Aged; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology; D014611:Vaccination