Development and Optimization of a GBS Diagnostic Test
Condition: Streptococcus Group B
Study type: Observational

Summary: 
      The purpose of this clinical study is to develop an easily performed test to detect Group B
      Streptococcus (GBS) in pregnant women at the time of delivery, which would allow health care
      providers to make an accurate and rapid decision regarding the administration of antibiotics.
      Administering antibiotics during delivery reduces significantly the likelihood of
      transmission of GBS, a bacterium that can cause severe life-threatening disease in newborns.
      Three hundred and twenty pregnant females between 18 to 44 years of age, who are admitted for
      delivery at the time of consent, will be recruited at the Centre Hospitalier Universitaire de
      Quebec. Participation involves being observed for 30 minutes. The research nurse will obtain
      2 vaginal/anal samples using standard techniques. One sample will be used to detect GBS with
      the approved BD GeneOhm StrepB assay and the other sample will be used for the development of
      the new point-of-care rapid detection GBS test.
    

Detailed description: 
      Group B Streptococcus (GBS), also known as Streptococcus agalactiae, is a gram-positive
      diplococcus originally known for causing bovine mastitis and was not demonstrated to be a
      human pathogen until 1938. In the 1970s, GBS emerged as the leading cause of neonatal
      morbidity and mortality. GBS causes severe invasive disease in newborns. Approximately 80% of
      infections in young infants occur within the first week of life and are thus designated as
      early-onset disease. Late-onset infections usually occur in infants between 1 week and 3
      months of age. Young infants with invasive GBS disease usually have sepsis or pneumonia but
      may, though less frequently, present with meningitis, osteomyelitis, or septic arthritis.
      Bloodstream infections, with or without pneumonia, are the main manifestation of neonatal GBS
      disease and are observed in approximately 90% of cases, while meningitis occurs in around
      10%. Most early-onset disease results from ascending spread of GBS into the amniotic fluid,
      which leads to neonatal colonization and to invasive disease in some infants. Perinatal
      transmission of the organism can occur through both ruptured and intact membranes.
      Transmission from mother to child has been reported to be 29 times higher in GBS-colonized
      mothers than in noncolonized mothers. The new Centers for Disease Control and Prevention
      guidelines recommend universal prenatal culture-based screening for GBS colonization in all
      pregnant women. A more sensitive rapid-screening test for GBS that could accurately detect
      women who carry GBS at the time of delivery would obviate the need for prenatal screening
      while reducing the risk associated with the use of intrapartum prophylaxis with antibotics in
      non-colonized women. The main objective of the study is to develop and optimize a micro TAS
      prototype for rapid GBS detection directly from vaginal/anal specimens using swabs collected
      from pregnant women admitted for delivery. It is expected that this diagnostic system can
      replace the current "gold standard" which is microbiological culture in selective media for
      determining GBS colonization. Specific objectives of this study include: (1) analytical
      sensitivity of the micro TAS prototype (number of GBS colony forming units detected per
      vaginal/anal specimen) will be determined by using prospectively collected vaginal/anal
      specimens positive for GBS as well as negative vaginal/anal specimens that will be spiked
      with various numbers of GBS cells; (2) specificity of the micro TAS prototype (ability to
      detect specifically GBS nucleotide sequences without detecting other microbial species or
      human sequences) will be determined by using GBS-negative vaginal/anal specimens and; (3)
      sample analysis and performance of the micro TAS prototype will be compared to clinical
      samples with FDA-approved BD GeneOhm StrepB assay . Study participants will include 320
      pregnant females between 18 to 44 years of age, who are admitted to the Centre Hospitalier
      Universitaire de Québec for delivery. Participation involves being observed for 30 minutes.
      The research nurse will obtain 2 vaginal/anal samples using standard techniques. One sample
      will be used to detect GBS with the approved BD GeneOhm StrepB assay and the other sample
      will be used for the development of the new point-of-care rapid detection GBS test.
    

Observational model: Case-Only
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Pregnant women admitted for delivery at the Centre Hospitalier Universitaire de Québec
        (CHUQ)
      
Biospecimen description: 
      Vaginal/anal swab samples taken from pregnant women admitted for delivery to the Centre
      Hospitalier Universitaire de Québec (CHUQ).
    
Keywords: Group B Streptococcus, Strepotococcus agalactiae, detection