Serological epidemiological studies with influenza A viruses.
D000293:Adolescent; D000328:Adult; D000906:Antibodies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D066298:In Vitro Techniques; D007223:Infant; D007251:Influenza, Human / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009500:Neutralization Tests; D009975:Orthomyxoviridae