Interest of the Detection of Hyper-virulent Clone ST17 of Group B Strep (GBS) for the Prevention of Neonatal GBS Meningitis (Col-Strepto B)

• Detection of the hyper-virulent ST17 clone of Group B Strep [ Time Frame: at 60 days post delivery ] [ Designated as safety issue: No ]
  Detection of the hyper-virulent ST17 clone of Group B Strep (GBS) in the prevention of neonatal GBS meningitis. The main objective is to demonstrate that the hypervirulent ST17 GBS clone colonizing the mother and postpartum acquired colonizes and persists at 60 days post delivery in the gut of new born significantly more than non-ST17 GBS strains.
  
  

• Digestive colonization [ Time Frame: at day 21 ] [ Designated as safety issue: No ]
  Digestive colonization of ST17 clone of Group B Strep in the newborns
  
  
• Milk colonization [ Time Frame: at day 21 and day 60 ] [ Designated as safety issue: No ]
  Colonization of milk by ST17 clone of Group B Strep
  
  
• Vaginal colonization [ Time Frame: at day 21 and day 60 ] [ Designated as safety issue: No ]
  Vaginal colonization by ST17 clone of Group B Strep
  
  
• Late neonatal infections [ Time Frame: between 3 weeks and 60 days ] [ Designated as safety issue: No ]
  Late neonatal infections will be observed between 3 weeks and 60 days
  
  

Women tested positive for GBS during systematic vaginal screening at 35-37 weeks, will be proposed to participate to the study and will be included after reading the information letter and signature the consent form.

INCLUSION (D0 at time of delivery)

In the labor ward, two women's groups 1 and 2:

Group 1 = Women tested positive for GBS pre-selected and included in the protocol (see pre-inclusion) Group 2 = Women without antenatal vaginal screening and at risk of neonatal infection.

For both groups, at time of delivery:

At the beginning of the labour performed vaginal swabs (PV0):

• one swab for GBS detection by real-time PCR using the Cepheid technique conducted in the labor ward by the midwife.
• the second swab for GBS detection by conventional bacteriological techniques and sent to the bacteriology laboratory.

For all women included (Group 1 and Group 2 women with a positive GBS vaginal sample) will be achieved in the delivery room:

1. To the mother: A blood sample of 5 ml at the time of the implementation of the IV line.
2. A sampling of umbilical cord blood. Newborns of mothers included (group 1 and 2) will have a search for GBS (standard culture) in the stools and the pharynx prior to return home. Samples will be sent to the bacteriology laboratory and analyzed by classical bacteriological method (culture) and / or real-time PCR.

For mothers, the collection of 3-5 ml of milk when breastfeeding.

Monitoring schedule:

Day 21 and day 60 post delivery:

the following samples for search of GBS for will be performed to gather the primary endpoint:

For the mother:

• Vaginal sample.
• Collection of 3-5 ml of breast milk when breastfeeding

For the newborn:

• Sample collection of feces
• Swab of buccal cavity

Processing bacteriological samples:

All samples will be subjected to bacteriological analysis and DNA extraction for detection of GBS. GBS isolated will be identified and stored at - 80 ° C in a declared biological collection. DNA extracts will also stored at -20 ° C in a declared biological collection. All samples for microbiological analysis will be stored at - 80 ° C.