The incidence of HI antibody to Influenza virus A2/Singapore/ 1/57 in individuals of blood groups A and O.
D000017:ABO Blood-Group System; D000328:Adult; D000906:Antibodies; D002648:Child; D002675:Child, Preschool; D004739:England; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007223:Infant; D007251:Influenza, Human / Q000453:epidemiology* / Q000276:immunology; D008875:Middle Aged; D011247:Pregnancy
D000017:ABO Blood-Group System; D000906:Antibodies