title: Phylogenetic lineages of invasive and colonizing strains of serotype III group B Streptococci from neonates: a multicenter prospective study.
abstract: This study compares the phylogenetic lineages of invasive serotype III group B streptococci (GBS) to those of colonizing strains in order to determine lineages associated with invasive disease. Isolates from 29 infants with early-onset disease (EOD) and from 196 colonized infants, collected in a prospective, multicenter study, were assigned a sequence type (ST) by multilocus sequence typing. Overall, 54.5% of the isolates were in the ST-19 complex, and 40.4% were in the ST-17 complex. Invasive strains were more likely to be in the ST-17 complex than were colonizing strains (59% versus 38%, P = 0.03). After we adjusted for potential confounders, the ST-17 complex was more likely to be associated with EOD than were other lineages (odds ratio = 2.51, 95% confidence interval = 1.02 to 6.20). These data support the hypothesis that ST-17 complex GBS are more virulent than other serotype III GBS.
authors.affiliation: National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-7510, USA. Link@exchange.nih.gov
authors.forename: Feng-Ying C
authors.initials: FY
authors.lastname: Lin
authors.forename: April
authors.initials: A
authors.lastname: Whiting
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Adderson
authors.forename: Shinji
authors.initials: S
authors.lastname: Takahashi
authors.forename: Diane Marie
authors.initials: DM
authors.lastname: Dunn
authors.forename: Robert
authors.initials: R
authors.lastname: Weiss
authors.forename: Parvin H
authors.initials: PH
authors.lastname: Azimi
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Philips
authors.forename: Leonard E
authors.initials: LE
authors.lastname: Weisman
authors.forename: Joan
authors.initials: J
authors.lastname: Regan
authors.forename: Penny
authors.initials: P
authors.lastname: Clark
authors.forename: George G
authors.initials: GG
authors.lastname: Rhoads
authors.forename: Carl E
authors.initials: CE
authors.lastname: Frasch
authors.forename: James
authors.initials: J
authors.lastname: Troendle
authors.forename: Patricia
authors.initials: P
authors.lastname: Moyer
authors.forename: John F
authors.initials: JF
authors.lastname: Bohnsack
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D015373:Bacterial Typing Techniques / Q000379:methods; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010802:Phylogeny; D011446:Prospective Studies; D012703:Serotyping; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000276:immunology / Q000635:transmission; D013292:Streptococcus agalactiae / Q000145:classification* / Q000235:genetics / Q000472:pathogenicity*
chemical_list: D000907:Antibodies, Bacterial