The United Nation's 7th Millennium Development Goal aims to reduce by half the number of people without sustainable access to safe drinking water. Safe water is critical to preventing diarrheal disease, which kills 2 million children annually. A promising household water treatment technology is the BioSand water filter (BSF), an intermittent slow sand filter that is locally made in Cambodia and several other developing countries. The BSF however, lacks adequate characterization and rigorous epidemiological evidence on its performance. The purpose of this research was to assess: (1) the factors associated with filter use and disuse by using a cross-sectional survey (2), the microbiological effectiveness of the BioSand filters still being used by reduced E. coli, and (3), the health impact of the BioSand filters as determined by a longitudinal, prospective cohort study in which diarrheal disease prevalence was measured among people in filter (intervention) households versus people in matched non-filter, control households.Master of Public Healt
