title: Influenza virus titration, antigenic characterization, and serological methods for antibody detection.
abstract: This chapter describes some commonly used methods of influenza virus titration, antigenic characterization, and serological methods by antibody detection. These methods are essential not only for virus characterization but also for identifying new antigenic variants, vaccine strain selection, and sero-epidemiologic studies of influenza virus transmission and prevalence. Virus titration methods such as the hemagglutination assay, 50% egg or tissue culture infectious dose, and plaque assay are employed to determine the amount of virus particles in a sample. The hemagglutination inhibition assay is a reliable, relatively simple and inexpensive technique to antigenically characterize isolates of influenza viruses. Serological methods such as virus neutralization and hemagglutination inhibition are the fundamental tools used in sero-epidemiologic studies of influenza virus transmission and prevalence and in the evaluation of vaccine immunogenicity. While serological methods rarely yield an early diagnosis of acute influenza virus infection, well-timed, paired acute, and convalescent serum samples may establish the diagnosis of a recent influenza infection even when attempts to detect the virus are negative.
authors.affiliation: Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA. AKlimov@cdc.gov
authors.forename: Alexander
authors.initials: A
authors.lastname: Klimov
authors.forename: Amanda
authors.initials: A
authors.lastname: Balish
authors.forename: Vic
authors.initials: V
authors.lastname: Veguilla
authors.forename: Hong
authors.initials: H
authors.lastname: Sun
authors.forename: Jarad
authors.initials: J
authors.lastname: Schiffer
authors.forename: Xiuhua
authors.initials: X
authors.lastname: Lu
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Katz
authors.forename: Kathy
authors.initials: K
authors.lastname: Hancock
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis* / Q000276:immunology; D000956:Antigens, Viral / Q000032:analysis* / Q000276:immunology; D002460:Cell Line; D002642:Chick Embryo; D004285:Dogs; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007251:Influenza, Human / Q000175:diagnosis* / Q000276:immunology / Q000821:virology; D009500:Neutralization Tests; D009975:Orthomyxoviridae / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D009976:Orthomyxoviridae Infections / Q000175:diagnosis* / Q000276:immunology / Q000821:virology; D010948:Viral Plaque Assay
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral