title: High group B streptococcus carriage rates in pregnant women in a tertiary institution in Nigeria.
abstract: BACKGROUND
  In contrast to industrialized countries, until recently Group B Streptococcus (GBS) was infrequently reported in the developing world. This study was aimed at investigating the prevalence of GBS maternal colonization and to analyze the serotype distribution among the isolates.
  
  
  METHODS
  Vagino-rectal swabs collected from pregnant women were cultured for GBS using conventional media. Swabs were also taken from the mouths, ears and umbilical stumps of the neonates born to colonized mothers. Multiplex PCR and a conventional PCR to discern thegbs2018-ST-17 gene (specific for sequence type(ST)-17 clone) was performed to characterize the Group B streptococcus isolates.
  
  
  RESULTS
  A total of 300 pregnant women and 53 neonates were studied by culture but only 175 mothers by PCR. GBS was identified in four (6.8%) of 59 (19.7%) neonates of colonized mothers. Out of 175 mothers investigated by PCR, 112 (64%) were colonized. Serotype Ia (23.9%) was the most common among vagino-rectal isolates. Serotype II (71.4%) predominates among colonizing strain in newborns. A significant association between frequency of intercourse of > 2 per week and GBS carriage was found (t-test= 2.2; P value < 0.05).
  
  
  CONCLUSIONS
  GBS carriage is high with low transmission. Strains that have been associated with GBS neonatal disease were reported, though in very low rates. Though none of the babies studied had invasive GBS disease, a more expansive study in the future will be required to establish if invasive GBS neonatal disease is uncommon in Nigeria.
authors.affiliation: Department of Medical Microbiology & Parasitology, Ben Carson School of Medicine, Babcock University/Babcock University Teaching Hospitals, Ilisan-Remo, Ogun State, Nigeria; Department of Medical Microbiology & Parasitology, Lagos University Teaching Hospital, Idi-Araba, Lagos, Nigeria.
authors.forename: Charles John
authors.initials: CJ
authors.lastname: Elikwu
authors.affiliation: Department of Medical Microbiology & Parasitology, College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria.
authors.forename: Oyinlola
authors.initials: O
authors.lastname: Oduyebo
authors.affiliation: Department of Medical Microbiology & Parasitology, College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria.
authors.forename: Folasade Tolulope
authors.initials: FT
authors.lastname: Ogunsola
authors.affiliation: Department of Obstetrics & Gynaecology, College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria.
authors.forename: Rose Ihuoma
authors.initials: RI
authors.lastname: Anorlu
authors.affiliation: Department of Paediatrics and Child Health, College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria.
authors.forename: Christy Nene
authors.initials: CN
authors.lastname: Okoromah
authors.affiliation: Institut für Medizinische Mikrobiologie und Infektionsepidemiologie, Universitätsklinikum Leipzig, Germany.
authors.forename: Brigitte
authors.initials: B
authors.lastname: König
mesh_terms: D000293:Adolescent; D000328:Adult; D002353:Carrier State / Q000453:epidemiology; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D018445:Infectious Disease Transmission, Vertical; D008875:Middle Aged; D060885:Multiplex Polymerase Chain Reaction; D009549:Nigeria / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D015995:Prevalence; D012703:Serotyping; D013290:Streptococcal Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D013292:Streptococcus agalactiae / Q000302:isolation & purification*; D055815:Young Adult
keywords: GBS ST-17 lineage; GBS serotypes; Group B Streptococcus (GBS); Lagos; Nigeria; carriage; meningitis; pregnant women