title: IgA deficiency and influenza infection.
abstract: A prospective study of influenza was carried out on 90 blood donors deficient for serum IgA as tested with double immunodiffusion. Half of them lacked IgA even by radioimmunoassay (RIA). A correlation existed between serum haemagglutination-inhibiting (HI) antibody and resistance to infection, suggesting that the serum HI antibody was an important determinant of protection. The rate of infection as evidenced by a fourfold or greater rise in HI titre, was about the same in the RIA-negative and RIA-positive donors and slightly higher than the corresponding rate in pregnant women and in a ship's crew.
mesh_terms: D000328:Adult; D000368:Aged; D001782:Blood Donors; D004406:Dysgammaglobulinemia / Q000150:complications*; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D005779:Immunodiffusion; D007070:Immunoglobulin A / Q000032:analysis; D007153:Immunologic Deficiency Syndromes / Q000150:complications*; D007251:Influenza, Human / Q000276:immunology*; D008875:Middle Aged; D011247:Pregnancy; D011863:Radioimmunoassay
chemical_list: D007070:Immunoglobulin A