There are sound reasons to include both a Drinking Water and an Adequate Sanitation indicator in Environmental Health measurement. The WHO identifies diarrhea as the disease most attributable to quality of the local environment. It is estimated that environment factors account for 94% of the global disease burden for diarrhea (WHO 2006). Measures of Drinking Water and Adequate Sanitation correlate well with diarrheal diseases. One of the main causes of diarrheal disease is contamination by fecal-oral pathogens, which is largely caused by inadequate drinking water and sanitation infrastructure. The WHO has estimated that 88% of diarrhea cases result from the combination of unsafe drinking water, inadequate sanitation, and improper hygiene (WHO 2006 and Pruss-Ustun 2004a).
