title: Antibodies to capsular polysaccharides of group B Streptococcus in pregnant Canadian women: relationship to colonization status and infection in the neonate.
abstract: In a cohort study of 1207 pregnant women in Alberta, Canada, the serotype distributions of vaginal-rectal group B Streptococcus (GBS) isolates were compared with all isolates from neonates with invasive GBS disease identified by population-based surveillance. Serum concentrations of Ia, Ib, II, III, and V capsular polysaccharide (CPS)-specific IgG also were determined, according to serotype of the vaginal-rectal colonizing GBS strain. GBS colonization was detected in 19.5% (235 of 1207) of women. Serotype III accounted for 20.6% (48 of 233) of colonizing strains available for typing but for 37% (27 of 73) of invasive isolates from neonates (P<.01). Maternal colonization with type III was least likely to be associated with moderate concentrations of III CPS-specific IgG. Serotype III GBS is more invasive than other serotypes in this population; this may be due, at least in part, to poor maternal type III CPS-specific antibody response.
authors.affiliation: Departments of Microbiology and Infectious Disease, Pediatrics, and Community Health Sciences and Child Health Research Unit, Alberta Children's Hospital, University of Calgary, Calgary,T2T-5C7, Canada. dele.davies@crha-health.ab.ca
authors.forename: H D
authors.initials: HD
authors.lastname: Davies
authors.forename: C
authors.initials: C
authors.lastname: Adair
authors.forename: A
authors.initials: A
authors.lastname: McGeer
authors.forename: D
authors.initials: D
authors.lastname: Ma
authors.forename: S
authors.initials: S
authors.lastname: Robertson
authors.forename: M
authors.initials: M
authors.lastname: Mucenski
authors.forename: L
authors.initials: L
authors.lastname: Kowalsky
authors.forename: G
authors.initials: G
authors.lastname: Tyrell
authors.forename: C J
authors.initials: CJ
authors.lastname: Baker
mesh_terms: D000328:Adult; D000416:Alberta; D000907:Antibodies, Bacterial / Q000097:blood*; D002170:Canada; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D010298:Parity; D011135:Polysaccharides, Bacterial / Q000276:immunology; D011159:Population Surveillance; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000382:microbiology*; D012007:Rectum / Q000382:microbiology; D012703:Serotyping; D013290:Streptococcal Infections / Q000097:blood / Q000276:immunology* / Q000635:transmission*; D013292:Streptococcus agalactiae / Q000276:immunology* / Q000302:isolation & purification; D014621:Vagina / Q000382:microbiology
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D011135:Polysaccharides, Bacterial