Investigating transmission of GBS to newborn babies in Malawi
Genetic fingerprinting techniques to investigate the relationship between GBS bacteria carried by mothers and those causing severe GBS disease in newborns in Malawi
Dr Emma Wall, Dr Macpherson Mallewa, Dr Queen Dube, Professor Neil French, Professor Robert Heyderman
- Start Date:
01 March 2014
University of Malawi, Blantyre, Malawi
What is this project about?
This project aims to understand how bacteria called GBS (Group B Streptococcus), which cause meningitis and severe blood poisoning, are transmitted to newborn babies in Africa. Professor Heyderman and his team will use state-of the art genetic fingerprinting techniques to investigate the relationship between GBS bacteria carried by mothers and those causing severe GBS disease in newborns in Malawi. They will also use this information to work out whether GBS transfer from mother to child occurs only around the time of birth or can happen later in the first month of life which is the main danger period for severe GBS infection in Malawi.
Our specialist clinical team will recruit and follow-up pregnant women and their babies at a local health-centre in Blantyre, Malawi to provide a collection of paired mother-baby GBS samples that will add to an existing large collection of GBS samples. Using genetic fingerprinting, they will then compare mother and child GBS, to better understand the origin of disease-causing GBS.
Why is it important?
The last ten years have seen major improvements in the number of deaths in children under 5 years old in many regions of Africa. However, newborn deaths are still unacceptably high. GBS meningitis and severe bloodstream infection are large contributors to this very high disease burden in Malawi and many other resource-poor settings. Urgent action is therefore needed to improve this situation and prevention of GBS is therefore an important public health priority. GBS could be prevented by giving antibiotics to mothers around the time of birth (called IAP) or vaccinating mothers against GBS. Vaccines are currently being tested but it may be 5-10 years before an effective vaccine can be introduced into routine programmes. For either vaccines or IAP to be implemented effectively, we need to know where the GBS that causes life-threatening disease in newborns comes from. This project will address this question.
What is genetic fingerprinting?
Each strain of GBS bacteria carries a unique genetic code, so that some strains inherit an ability to transfer especially easily from mother to child or to cause disease.
This unique code means that each strain has a fingerprint and can be distinguished from others. This project will use state of the art techniques to look at the genetic code of GBS from both mothers and their children to see which strains are being transmitted.
This project will produce data that will be vital for understanding GBS meningitis and severe bloodstream infections in developing countries, as well as the likely benefits of IAP. It will also provide crucial data for the design and implementation of novel GBS vaccines in a large efficacy trial.
Malawi-Liverpool-Wellcome Trust clinical research programme
This is a major collaboration between University of Liverpool, Liverpool School of Tropical Medicine and University of Malawi College of Medicine. Professor Robert Heyderman is the Director of the programme.www.mlw.medcol.mw/
This work follows on from another MRF funded study in Malawi, which ended in 2010. Samples were collected from 1857 pregnant women to investigate the effect of HIV status on carriage of GBS bacteria. Does HIV infection boost carriage of Group B streptococcus bacteria in pregnant women and increase the risk of infection in new born babies?
This current study will add to that collection by including paired samples from both mothers and their babies. The research team are interested in comparing the genetic fingerprints of this large collection with their collected samples.