title: EXTENT OF ANTIGENIC VARIATION OF A2 INFLUENZA VIRUSES FROM PROTOTYPE STRAINS.
mesh_terms: D000906:Antibodies; D000940:Antigenic Variation; D004813:Epidemiology; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007251:Influenza, Human; D008889:Military Personnel; D009500:Neutralization Tests; D009975:Orthomyxoviridae; D012106:Research; D014481:United States
chemical_list: D000906:Antibodies
keywords: ANTIBODIES; EPIDEMIOLOGY; EXPERIMENTAL LAB STUDY; HEMAGGLUTINATION INHIBITION TESTS; INFLUENZA; MILITARY PERSONNEL; NEUTRALIZATION TESTS; UNITED STATES