Phylogenetic lineages of invasive and colonizing strains of serotype III group B Streptococci from neonates: a multicenter prospective study.
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.
Lin
Feng-Ying C
FY
National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-7510, USA. Link@exchange.nih.gov
Whiting
April
A
Adderson
Elisabeth
E
Takahashi
Shinji
S
Dunn
Diane Marie
DM
Weiss
Robert
R
Azimi
Parvin H
PH
Philips
Joseph B
JB
Weisman
Leonard E
LE
Regan
Joan
J
Clark
Penny
P
Rhoads
George G
GG
Frasch
Carl E
CE
Troendle
James
J
Moyer
Patricia
P
Bohnsack
John F
JF
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*
D000907:Antibodies, Bacterial