Swine flu: problem or panic.
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D006801:Humans; D007114:Immunization; D009980:Influenza A virus; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control*; D008875:Middle Aged; D009975:Orthomyxoviridae; D014481:United States