Diarrhoea is characterized by diverse clinical syndromes, but more commonly the passage of abnormally loose stool or stool mixed with blood and mucus.The WHO estimates that 18% of the 10.6 million children in the under five age group die from diarrhoeal diseases each year. Under-5 mortality rates fell worldwide throughout the latter part of the 20th century from 146 per 1000 in 1970 to 79 per 1000 in 2003. Since 1990, this rate has dropped by about 15%, amounting to more than two million lives spared in 2003 alone. But this trend is not uniform across the globe; the rate reduction was about 50% or more in Asia and America while it was much lower in Africa. The factors impeding progress in child health in Africa are not clearly defined, particularly when it comes to diarrhoeal disease.

Even though the disease causes such high rates of illness and death, there is a lack of a well designed study to look at the epidemiology and aetiology, making it difficult to manage and contain. Apart from the classical questions of epidemiology (WHO, WHEN and WHERE), there is also a need to look at WHY some suffer while others do not and WHAT happens due to the disease in the short and long term and its social and economic impact.

The Bill and Melinda Gates Foundation for the first time are funding a Global Enteric Multicenter Study (GEMS) to address the whole gamut of diarrhoeal disease in developing countries. Scientists from five sub-Saharan countries (The Gambia, Kenya, Mali, Mozambique and Tanzania) along with their counterparts in three South East Asian countries (Bangladesh, India and Pakistan) have joined experts from the Centre for Vaccine Development (CVD), the University of Maryland, the WHO and other reference centres for enteric research across the globe to accomplish this task.

Professor Richard Adegbola (Head of the Bacterial Diseases Programme) with Dr Debasish Saha (Clinical Epidemiologist), Dr Martin Antonio (Molecular Biologist) and Dr Momodou Jasseh (Demographer) are leading the Gambia team at MRC The Gambia’s field site in Basse. The team has successfully established a Demographic Surveillance System (DSS) in the South Bank Region, Upper River Region and Basse. It is the third MRC-led DSS in The Gambia after Keneba and Farafenni.

The Basse DSS is jointly funded by the GEMS, Pneumococcal Surveilance Project (PSP) and MRC The Gambia. The DSS holds a population of 136, 793 with 21,274 in the under five age group. One of the major components of the GEMS study is a Health Care and Utilization Survey (HUAS), which has also been completed and the data are being processed for analysis. This will give an insight into communities’ health seeking behaviours and attitudes towards diarrhoeal diseases.

The clinical team has been trained for the task and a ‘state of the art’ laboratory has been developed for the project at Basse. The estimated budget for the project is US$1.6 million and it will run for the next couple of years.

The GEMS team is working towards a better definition of the aetiology of these age-specific trends so that appropriate interventions can be designed and implemented. The future is defined clearly in the protocol when it states “Recent advances in biotechnology promise new approaches to the construction of enteric vaccines and to set priorities for enteric vaccine development, design vaccines for broad coverage, guide public health policy, and target appropriate interventions. There is a compelling need to determine the aetiology, burden, and sequelae of diarrhoeal diseases from multiple, heterogeneous geographic and epidemiologic settings. These data must be produced using methods that address deficiencies in previous studies, and must satisfy current needs for strategies that can diminish morbidity and mortality from diarrhoeal diseases, with a clear emphasis on children living in regions where mortality is high, such as in sub-Saharan Africa.”

MRC The Gambia is proud to be a partner in achieving this goal.

Bacterial Diseases Programme - MRC (UK) The Gambia