Investment in drinking water and sanitation infrastructure and its impact on waterborne diseases dissemination: The Brazilian case.

Investment in sanitation and drinking water infrastructure is essential for universal access to these services in developing countries. Universal coverage of water and sanitation services (WSS) can prevent the dissemination of waterborne diseases and mitigate their adverse effects. These diseases are responsible for many deaths worldwide, especially among the disadvantaged population and children. A causal effect can be established between WSS investment and hospital admissions due to waterborne diseases. Therefore, we considered an innovative network-DEA approach that models the link between serially connected subsystems (upstream investment and downstream hospitalizations). This approach allowed us: to measure the efficiency of both subsystems; estimate the amount of (efficient) investment necessary to universalize the access to proper WSS infrastructure; and mitigate hospital admissions due to waterborne diseases. We used the Brazil case study to test our model. On average, Brazilian states could increase the number of people not requiring hospitalizations due to waterborne diseases by 157 thousand per R$100 million invested in sanitation and 26 thousand per R$100 million invested in drinking water. Our results suggest that relatively small (efficient) investment in those two infrastructure types has a massive impact on hospitalizations. This impact would be more significant than the investment in WSS coverage. Therefore, if safely managed, WSS would cover all citizens, and Brazil would come closer to developed countries.