title: An influenza index on periodic determination of average antibody titers of population samples.
authors.forename: B S
authors.initials: BS
authors.lastname: SCHWARTZ
authors.forename: J H
authors.initials: JH
authors.lastname: MILSTONE
mesh_terms: D006801:Humans; D007109:Immunity; D007251:Influenza, Human / Q000453:epidemiology* / Q000706:statistics & numerical data*