GAMI protocol v1.0 17.1.14.pdf (857.72 kB)
Group B Streptococcal Antibody in Mothers and Infants (GAMI): Study protocol to describe the strain-specific prevalence of Group B Streptococcus carriage in women and their infants in Gambia
online resource
posted on 2020-12-17, 14:44 authored by Kirsty Le DoareGroup-B streptococci: developing a correlate of protection for future vaccine trials with the help of pregnant Gambian women and their infants. Study protocol.
Objectives: To determine risk factors for GBS colonisation in Gambian
mothers and in their infants from birth to day 60-89 of age.
Methods:
Swabs and breastmilk from mothers/infant pairs were collected and
cultured on selective agar. Negative samples were analysed for GBS DNA
via real-time PCR. Positive isolates were serotyped using multiplex PCR
and gel-agarose electrophoresis.
Results: Seven hundred and fifty
women/infant pairs were recruited. 253 women (33.7%) were GBS-colonised
at delivery. The predominant serotypes were: V (55%), II (16%), III
(10%), Ia (8%) and Ib (8%). 186 infants were colonised (24.8%) at birth,
181 (24.1%) at 6 days and 96 at day 60-89 (14%). Infants born before 34
weeks of gestation and to women with rectovaginal and breastmilk
colonisation at delivery had increased odds of GBS colonisation at
birth. Season of birth was associated with increased odds of persistent
infant GBS colonisation (dry season vs. wet season AOR 2.9; 95% CI
1.6-5.2).
Conclusion: GBS colonisation is common in Gambian women at
delivery and in their infants to day 60-89 and is dominated by serotype
V. In addition to maternal colonisation, breastmilk and season of birth
are important risk factors for infant GBS colonisation.
Funding
Wellcome Trust Clinical Research Fellowship (WT104482MA)
Thrasher Research Fund (BK: 12250)
History
Research Institute
- Infection and Immunity