Closing the gap : applying health and socio-demographic surveillance to complex health transitions in South and sub-Saharan Africa

Background: The challenge of research in resource-poor settings remains a profound concern and is closely linked to African social development. Work of this thesis spans the end of apartheid and first decade of the democratic era in South Africa, along with emergence of the HIV/AIDS pandemic. It also covers the founding decade of the INDEPTH Network. Aims: Through appraising health and population research in a rural southern African sub-district over the past decade, to evaluate the utility of health and socio-demographic surveillance in rural African settings for: • capturing the dynamics of health, population and social transitions • supporting a mix of research designs, and • contributing to policy and programme development and evaluation. To extend this appraisal by examining the multi-site opportunities offered by the INDEPTH Network. Methods: Work was sited in the Agincourt sub-district, a heavily populated border area of rural north-eastern South Africa. Health and socio-demographic surveillance, introduced in 1992, involved prospective follow-up of the entire sub-district population of 70,000 people (including some 30% Mozambican immigrants) who lived in 11,700 households and 21 villages. Annual census rounds systematically updated household membership and recorded all vital events (births, deaths and migrations) since the previous census. A maternity history was asked of women of reproductive age and a verbal autopsy carried out on all deaths registered. The resulting ‘data and research platform’ – a core feature of all INDEPTH field sites – provided data for computation of trends in vital events and supported an extensive interdisciplinary project portfolio. The population under surveillance can be disaggregated into cohorts selected by age, sex or other criteria. Analyses are possible at multiple levels (individual, family/household or neighborhood) and can include socioeconomic factors. Findings: The Agincourt community experienced a serious worsening of mortality among most age-sex groups, rapidly declining fertility to near replacement level, and changing patterns of labour migration. This resulted in major changes in population structure and household composition. The rising burden of chronic disease involved both chronic infectious illness (HIV/AIDS and tuberculosis) and non-communicable disorders (such as stroke and related vascular disease). The burden of illness requiring chronic care increased disproportionately to that needing acute care. Potential contributions of field sites based on health and socio-demographic surveillance to local and national health policy are considerable yet remain underexploited. Interpretation: Rural South and southern Africa is in the midst of multiple, interrelated transitions with implications for health, social and development sectors. Health and socio-demographic surveillance systems are effective research instruments that can capture the rapidly-changing dynamics of health and social transitions in developing settings. Similarly, they can support a range of observational and intervention study designs including policy evaluations. The INDEPTH Network should boost much-needed comparative research; yet singly, and as a group, many of these sites have yet to fulfil their undoubted potential