Water Quality in South Asia

Correspondence and reprint requests should be addressed to: Dr. Stephen Luby Head, Programme on Infectious Diseases and Vaccine Sciences ICDDR,B GPO Box 18, Dhaka 1000 Bangladesh Email: [email protected] Fax: 880-2-8823963 Water, an essential compound for human life, all too often carries pathogens that cause disease. The article by Tambe et al. illustrates a community where half the time the available drinking-water was contaminated with organisms whose ecological niche is the human intestine (1). This finding is common throughout South Asia where both urban and rural water supplies are frequently contaminated with human faecal organisms. Although 85% of drinking-water in South Asia meets the target of the Millennium Development Goal of coming from an improved source (2), this water is, in fact, frequently contaminated with human faecal organisms (1,3,4). Indeed, the frequency of water contamination with human faeces is so common throughout South Asia that it is accepted as the norm. Those who can afford it buy bottled water (of dubious quality), and the majority are left to drink the available contaminated water. The commonality of this contamination risks preventing us from appreciating the seriousness of the problem. In the United States, at the beginning of the twentieth century, most large cities were served by municipal water suppliers that distributed untreated water throughout the city. Immediately following the introduction of effective water treatment, overall child mortality dropped by 46% in major US cities (5). Moreover, the microbiological contamination of water not only causes childhood death, but also repeated bouts of diarrhoea among children aged less than two years impair cognitive development and school performance among survivors (6,7). Thus, the failure to deliver clean water to the population of South Asia means more childhood deaths, less cognitive development, less educational achievement, and less economic growth.