Antibody Correlates and Predictors of Immunity to Naturally Occurring Influenza in Humans and the Importance of Antibody to the Neuraminidase

• Published in: The Journal of infectious diseases Vol. 207; no. 6; pp. 974 - 981
• Main Authors: Couch, Robert B., Atmar, Robert L., Franco, Luis M., Quarles, John M., Wells, Janet, Arden, Nancy, Niño, Diane, Belmont, John W.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 15.03.2013
• Subjects: Adolescent; Adult; Antibodies; Antibodies, Viral - blood; Biological and medical sciences; Chi-Square Distribution; Diseases; Female; Fundamental and applied biological sciences. Psychology; H1N1 subtype influenza A virus; Hemagglutination Inhibition Tests; Hemagglutinin Glycoproteins, Influenza Virus - immunology; Humans; Immunity; Immunoglobulin A - analysis; Immunoglobulin G - analysis; Infections; Infectious diseases; Influenza; Influenza A Virus, H1N1 Subtype - immunology; Influenza virus; Influenza, Human - immunology; Influenza, Human - virology; Logistic Models; Major and Brief Reports; Male; Medical sciences; Microbiology; Middle Aged; Nasal Lavage Fluid - chemistry; Nasal Lavage Fluid - immunology; Nasal Lavage Fluid - virology; Neuraminidase - immunology; Orthomyxoviridae; Predictive Value of Tests; Secretion; Severity of Illness Index; Statistics, Nonparametric; Vaccination; Viruses; Young Adult; Glycosylases; Human; Infection; Enzyme; Antibody; Glycosidases; Viral disease; Exo-α-sialidase; Influenza; Hydrolases
• ISSN: 0022-1899; 1537-6613; 1537-6613
• DOI: 10.1093/infdis/jis935

Background. Serum antibody to the hemagglutinin (HA) of influenza viruses is a correlate and predictor of immunity to influenza in humans; the relative values of other correlates are uncertain. Methods. Serum and nasal secretions (NS) were collected in fall and spring of 2009—2011 from healthy adults who were monitored for acute respiratory illness (ARI). Serum samples were tested for hemagglutination-inhibition (HAI) antibody increase and secretions for virus if ill; enrollment sera were also tested for neuraminidase-inhibiting (NI) antibody and NS for neutralizing (neut), NI, immunoglobulin A (IgA), and immunoglobulin G (IgG) anti-HA antibody. Results. Serum anti-HA and anti-neuraminidase (NA) antibody titers to 2009(H1N1) pandemic influenza virus (pH1N1) correlated with titers in NS (including IgA and IgG antibody). Increasing anti-HA and anti-NA titers in serum and NS tests all correlated with reducing infection and infection-associated illness. Multivariate analyses indicated serum HAI and NI each independently predicted immunity to infection and infection-associated illness. Only serum NI independently predicted reduced illness among infected subjects. Conclusions. Increasing anti-HA and NA antibody in serum and secretions correlated with reducing pH1N1 influenza virus infection and illness in healthy young adults. Both anti-HA and anti-NA antibody are independent predictors of immunity to influenza; ensuring induction of both by vaccination is desirable.