The AmBASS project was set up in Niakhar, Senegal, to better understand the extent and consequences of the Hepatitis-B infection on the living conditions of the populations affected and their households in rural environments, with a view to coming up with prevention and management policies which may be adequate and effective in this context.
Hepatitis B is a potentially fatal hepatic infection caused by the hepatitis B virus (HBV). It is transmitted through blood and other body fluids. According to the WHO, 257 million people are living with HBV infection and 887,000 people died from it in 2015. A major public health concern, this disease can be chronic and can expose patients to a high risk of death from cirrhosis and liver cancer. The prevalence of this disease is highest in the Pacific and Africa, with respectively 6.2% and 6.1% of the population infected. Although there are no population-level prevalence estimates in Senegal, this country is among the worst affected in the world, with an estimated prevalence rate of 11%. Yet a 95% effective vaccine has been available since 1982. This vaccine was integrated into Senegal’s expanded program on immunization in 2004 as part of the pentavalent vaccine, followed by vaccination at birth in 2016.
The Niakhar observatory is the oldest health and demographic monitoring system in Africa. Founded in 1962, this study site is located 155 km from Dakar, in the Fatick department. It consists of 30 villages with a population of 49,000.
Currently underway in the area of this observatory, the AmBASS project is led by two IRD teams in partnership with the European Hospital of Marseille and Senegal’s Institute for health research, epidemiological surveillance and training (Iressef). This project is based on a cross-sectional survey which includes at-home hepatitis B tests among a sample of 3,200 individuals, representative of the general population in the area. Data from this project will help provide an estimated prevalence of the hepatitis B virus in the general population of the Niakhar area, as well as among women of child-bearing age and among under 15, 15-35 and over 35 age groups.
To supplement the epidemiological data collected as part of the hepatitis B tests offered to all participants, the community survey also collects information on the socio-demographic and economic characteristics of households, as well as the individuals’ health, quality of life and access to healthcare. When participants are diagnosed with chronic hepatitis B, further tests are proposed in health centres.
In addition, information on how to prevent transmission risks is also provided to all participants during the reporting of results, and vaccination is offered to non-infected participants who are not immune to the hepatitis B virus.
Data collected will also help improve population health monitoring, enhance advocacy efforts for the economic feasibility of at-home tests and hepatitis B treatment scale-up.