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Water supply and sanitation as a ‘preventive medicine’: challenges in rapidly growing economies

World-wide, development agencies have increased their investment in this ‘powerful preventive medicine’ to address the growing threat from infectious diseases. Many of these infectious diseases, including malaria, diarrhoea, dengue and jaundice, are transmitted through water. This investment also gained momentum from the Millennium Development Goals (MDGs) (UN Millennium Project, 2005). In spite of these improvements, the incidence of waterand vector-borne diseases (WVDs) remains high. An evaluation of World Bank–funded water development projects between 1997 and 2007 concluded that “evidence of improved water quality is rare, as are indications of the improved health of project beneficiaries” (IBRD/WB, 2010, p. x). The report raised concern over “a declining emphasis on monitoring economic returns, water quality, and health outcomes” from various water projects (p. x). This special issue of Water International contributes to the topic by assessing the relevance of ‘preventive medicine’ (water supply and sanitation) in addressing WVDs in rapidly growing economies. The contributors to this special issue were expressly asked to assess the dynamics facilitating (or constraining) water supply and sanitation coverage and their implications for WVDs. These factors were explored in urban, peri-urban and rural contexts in the rapidly growing economies of Africa, Asia and Latin America. These economies are facing rising populations, increasing urbanization, intensification of agricultural practices and high social mobility, not to mention changes in climate. While on the one hand these countries enjoy new prosperity, on the other they face high levels of deprivation and severe capacity constraints in meeting their growing needs. These characteristics make them unique and also require immediate attention. The countries in these continents will continue to dominate global urban growth until 2030, with countries in Asia alone accounting for more than half the world’s urban population. These developments have not only created a major challenge for meeting the demand for water supply and sanitation, but also have significant impacts on human health. This special issue takes on the challenge of understanding the implications of water supply and sanitation for WVDs, reviewing our progress in meeting the MDGs through case studies. Saravanan, Johansen et al., Gondhalekar et al., and Babalobi focus on the growing challenge from rapid urbanization. On the other hand, Carino and Xie, as well as Zimmermann, state that rural areas are evolving towards reducing poverty, acknowledging human rights standards, reducing ethnic conflict and developing sustainable strategies. Developing countries face the enormous task of considering all these factors in meeting their growing drinking-water and sanitation needs. The concluding paper by Gondhalekar et al. considers the methods Water International, 2013 Vol. 38, No. 7, 867–874, http://dx.doi.org/10.1080/02508060.2013.857142