title: Association between maternal Group B Streptococcus surface-protein antibody concentrations and invasive disease in their infants.
abstract: OBJECTIVE
  Group B Streptococcus (GBS) surface-proteins have been shown to be immunogenic and potential vaccine candidates. We aim to determine the association between maternal IgG antibodies to select GBS surface-proteins and invasive GBS disease in their infants.
  
  
  METHODS
  Using a matched case-control study, maternal antibody levels for GBS-immunogenic bacterial adhesin, fibrinogen-binding protein A and pilus-island (PI) PI-1, PI-2a, PI-2b were compared between infants with invasive GBS disease and well-baby controls.
  
  
  RESULTS
  The absolute risk of disease did not differ between cases and colonized controls with increasing antibody concentrations for these surface-proteins. There was, however, a relative risk reduction in invasive disease associated with fibrinogen-binding protein A, with an adjusted odds ratio of 0.04 (95% CI: 0.01-0.69) at antibody levels ≥10,000 AU/ml.
  
  
  CONCLUSIONS
  We have not demonstrated an association between naturally occurring fibrinogen-binding protein A, GBS-immunogenic bacterial adhesin, and PI surface-protein antibodies and the risk of invasive disease in young infants. These surface-proteins may not be suitable GBS vaccine candidates.
authors.affiliation: a 1 Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|b 2 Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|c 3 Department of Paediatrics & Child Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Ziyaad
authors.initials: Z
authors.lastname: Dangor
authors.affiliation: a 1 Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|b 2 Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Gaurav
authors.initials: G
authors.lastname: Kwatra
authors.affiliation: a 1 Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|b 2 Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Alane
authors.initials: A
authors.lastname: Izu
authors.affiliation: a 1 Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|b 2 Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Peter
authors.initials: P
authors.lastname: Adrian
authors.affiliation: a 1 Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|b 2 Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Clare L
authors.initials: CL
authors.lastname: Cutland
authors.affiliation: c 3 Department of Paediatrics & Child Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Sithembiso
authors.initials: S
authors.lastname: Velaphi
authors.affiliation: c 3 Department of Paediatrics & Child Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Daynia
authors.initials: D
authors.lastname: Ballot
authors.affiliation: c 3 Department of Paediatrics & Child Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Gary
authors.initials: G
authors.lastname: Reubenson
authors.affiliation: d 4 Stat-Epi Associates, Inc., FL, USA.
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Zell
authors.affiliation: c 3 Department of Paediatrics & Child Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Sanjay G
authors.initials: SG
authors.lastname: Lala
authors.affiliation: a 1 Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|b 2 Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.|e 5 National Institute for Communicable Diseases: a division of National Health Laboratory Service, Centre for Vaccines and Immunology, Sandringham, South Africa .
authors.forename: Shabir A
authors.initials: SA
authors.lastname: Madhi
mesh_terms: D018829:Adhesins, Bacterial / Q000276:immunology; D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D000954:Antigens, Surface / Q000276:immunology*; D016022:Case-Control Studies; D005260:Female; D010861:Fimbriae, Bacterial / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D012306:Risk; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D013292:Streptococcus agalactiae / Q000276:immunology*
chemical_list: D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D000954:Antigens, Surface; D007074:Immunoglobulin G
keywords: BibA; FbsA; GBS; Group B Streptococcus; Streptococcus agalactiae; pilus island