Strep A is a common bacteria that causes illnesses including sore throat and skin infections. In some cases, infection can lead to severe invasive disease or trigger complications such as rheumatic heart disease (RHD), which disproportionately affects children and young adults, especially in vulnerable communities.
Despite its significant global burden, there is currently no licensed vaccine for Strep A. Understanding how the immune system responds after exposure, particularly during early life, is therefore critical for future vaccine development and disease prevention.
"This is a very exciting long-term study aiming to understand how exposure to Strep A in early life programmes the immune system and may result in protection from infection or the development of immune-mediated rheumatic heart disease. RHD is a devastating condition which can lead to heart failure and significant disability and death in early adulthood. We urgently need a vaccine against Strep A and this work will further this goal," said Professor Ed Clarke, Principal Investigator and Unit Director of MRCG at LSHTM.
A major component of the study will be the establishment of a new birth cohort in The Gambia. Infants will be followed from birth through their first two years of life, providing researchers with an opportunity to study how repeated exposure to Strep A during early childhood affects immune system development.
The study will also investigate why natural immunity to Strep A may develop poorly during early life, which immune responses provide protection against infection, and whether early biological responses may explain why some children later develop complications such as rheumatic heart disease.
Funded through a Wellcome Discovery Award, the seven-year programme brings together researchers from MRCG at LSHTM, the University of Sheffield in the UK, the University of Auckland in New Zealand, the Walter and Eliza Hall Institute in Australia, and Institute Pasteur in France. They will combine long-term clinical and epidemiological studies with advanced immunology, proteomics and mathematical modelling.
Dr Eunice Kiamba, Research Fellow at MRCG at LSHTM and Co-Investigator co-leading the cellular immunology component, said: "I am delighted to contribute to this important programme, which combines cutting-edge science with a strong commitment to strengthening research capacity in Africa."
The research will build on ongoing studies in The Gambia, Uganda and Malawi, where more than 22,000 children are being screened for early signs of rheumatic heart disease.
Dr Effua Usuf, Associate Professor at MRCG at LSHTM and co-lead of the epidemiology work, said: "Preventing this bacterial infection could transform the lives of children in The Gambia and beyond, sparing them from serious illness and the lifelong consequences of rheumatic heart disease."
In addition to research, the programme will strengthen scientific expertise and leadership in Africa, with advanced training for early career researchers in immunology, serology, epidemiology and data science.
