title: Antibodies to influenza A/swine-like viruses (Hsw1N1) in human sera: antigenic stimulation and changes in antibody status.
abstract: Human sera collected at the end of 1975 were studied for HI antibodies to influenza A/Mayo Clinic/103/74 (Hsw1N1). The frequent occurrence of these antibodies in subjects born before 1930 suggested that they are present in about 25% of the Finnish population. During the H3N2 epidemic in winter 1975-76 a low response of antibodies to A/swine-like viruses was recorded in about half of the influenza patients with a pre-existing titre, but not in any of the patients without pre-existing antibodies. A comparison of samples collected in 1969 and 1975 suggested that at the community level the antibodies to A/swine-like viruses have not decreased during the era of the H3N2 subtype.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000914:Antibodies, Viral / Q000032:analysis; D000956:Antigens, Viral; D002648:Child; D002675:Child, Preschool; D005387:Finland; D006801:Humans; D009980:Influenza A virus / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology*; D008875:Middle Aged
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral