title: Group B streptococcus late-onset disease: 2003-2010.
abstract: BACKGROUND
  There is insufficient population-based data on group B streptococcus (GBS) late-onset disease (LOD). Risk factors and routes of GBS transmission are poorly understood.
  
  
  METHODS
  A prospective, cohort study was conducted to collect incidence data on LOD and evaluate GBS infections over an 8-year period (2003-2010). Starting from January 2007, maternal rectovaginal and breast milk cultures were routinely collected on confirmation of the LOD diagnosis to assess maternal GBS culture status.
  
  
  RESULTS
  The incidence rate of LOD was 0.32 per 1000 live births (1.4 and 0.24 per 1000 live births for preterm and term newborns, respectively). The registered cases of LOD (n = 100) were classified as sepsis (n = 57), meningitis (n = 36), or focal infection (n = 7). Thirty neonates were preterm (2 had recurrent infection); 68 were term. Four infants died (3 early preterm, 1 term). At the time the LOD diagnosis was confirmed, 3 (6%) of 53 mothers had GBS mastitis, and 30 (64%) of 47 carried GBS at the rectovaginal site. Early (7-30 days) LOD presentation was associated with neonatal brain lesions or death (odds ratio: 0.96 [95% confidence interval: 0.93-0.99]). Intrapartum antibiotic exposure was significantly associated with mild (12 of 22) rather than severe (11 of 45; P = .03) LOD.
  
  
  CONCLUSIONS
  Preterm neonates had the highest rates of LOD and mortality. Most mothers carried GBS at the time of the LOD diagnosis, whereas 6% had mastitis. Intrapartum antibiotics were associated both with delayed presentation of symptoms and milder LOD.
authors.affiliation: Unità Operativa di Terapia Intensiva Neonatale, Azienda Ospedaliero-Universitaria Policlinico, Via del Pozzo, 71-41124 Modena (MO), Italy. berardi.alberto@policlinico.mo.it
authors.forename: Alberto
authors.initials: A
authors.lastname: Berardi
authors.forename: Cecilia
authors.initials: C
authors.lastname: Rossi
authors.forename: Licia
authors.initials: L
authors.lastname: Lugli
authors.forename: Roberta
authors.initials: R
authors.lastname: Creti
authors.forename: Maria Letizia
authors.initials: ML
authors.lastname: Bacchi Reggiani
authors.forename: Marcello
authors.initials: M
authors.lastname: Lanari
authors.forename: Luigi
authors.initials: L
authors.lastname: Memo
authors.forename: Maria Federica
authors.initials: MF
authors.lastname: Pedna
authors.forename: Claudia
authors.initials: C
authors.lastname: Venturelli
authors.forename: Enrica
authors.initials: E
authors.lastname: Perrone
authors.forename: Matilde
authors.initials: M
authors.lastname: Ciccia
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Tridapalli
authors.forename: Marina
authors.initials: M
authors.lastname: Piepoli
authors.forename: Raffaella
authors.initials: R
authors.lastname: Contiero
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Ferrari
mesh_terms: D017668:Age of Onset; D019072:Antibiotic Prophylaxis; D002353:Carrier State; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D007558:Italy; D008297:Male; D008895:Milk, Human / Q000382:microbiology; D011247:Pregnancy; D011446:Prospective Studies; D012007:Rectum / Q000821:virology; D012307:Risk Factors; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission*; D013292:Streptococcus agalactiae; D014621:Vagina / Q000821:virology