Impact of Water and Sanitation Interventions on Childhood Diarrhea: Evidence from Bangladesh

This paper analyses the possible relevance of water and sanitation improvements for diarrhoea reduction in the context of Bangladesh. Much of the public policy thinking in the past was guided by public investment in providing improved access to water. The paper provides evidence that the relevance of water as a tool for fighting diarrhoea may have changed over time although in the past it had done so. However, recent loss of efficacy of improved water in Bangladesh while may have something to do with water quality but more importantly certain environmental developments causing tube well users to rely on unsafe sources for drinking water may also be confounding the water effect. The sanitation intervention has some impact but as the results of the present paper suggest a combined access to improved water and sanitation has greater policy validity now than was the case before. This paper utilized household data collected by the Bangladesh Demographic and Health Survey for 1996/97 and 2007 rounds. Using propensity score matching (PSM) technique, it was found that in 2007 the combined access to improved water and sanitation can lead to reduced incidence of diarrhoea among children significantly both in contrast to their isolated use and non-use of any improved sources. For 2007, the mean probability of childhood diarrhoea incidence for those who have combined access to water and sanitation is 31.5 per cent lower than in case of those without the combined access to water and sanitation in the PSM matched sample. Such observations were however, found absent with 1996/97 data. Thus, the present analyses/ results suggest a case for rethinking public policy at least at present by way of joint investment in water and sanitation (WatSan) measures to reduce diarrhoea in future.