In developing countries, 2.6 billion people lack access to basic sanitation and 1.1 billion do not have access to improved water sources. This combination leads to 1.6 million deaths each year from preventable diarrheal diseases, 90% of which are among children less than 5 years of age.1
The Millennium Development Goals' target for improvement is to reduce by half the proportion of people without access to safe drinking water by 2015.2
The optimal approach to preventing water-borne diseases includes the construction of water disinfection and delivery systems and sewage treatment facilities, which is expensive and time-consuming. In tropical developing countries, even if facilities are developed, their maintenance and monitoring may not be reliable because of a variety of factors.
Previous studies in India have shown that many of the public water sources that serve both the peri-urban and rural areas are often contaminated and the type of pathogens vary in each outbreak.3–6
Even when population-based methods of water purification, such as chlorination of tanks, are successful, practices in the home, such as dipping tumblers or cups into wide-mouthed containers to obtain water, can cause recontamination.7
Studies have shown that in the absence of recontamination, counts of thermotolerant coliforms will decrease significantly over hours to days in stored water samples.8
Water storage containers, which prevent in-home contamination, can lead to almost 70% reduction in coliform counts and 31% reduction in diarrhea in children.9
A combination of point-of-use disinfection methods and prevention of recontamination is likely optimal, but difficult to achieve. Boiling, one of the most common methods of disinfection used in settings with contaminated water sources, is expensive and time-consuming.10
Two promising alternative technologies for point-of-use decontamination are the use of M. oleifera
seed preparations and in-home chlorination.
The use of natural materials of plant origin to clarify turbid surface waters can be found in many cultures. Sanskrit writings in India dating from several centuries BC make reference to seeds of the tree Strychnos potatorum
as a clarifier. Moringa oleifera
seeds were first used for domestic household water treatment by women in the Sudan, who placed powdered seeds in a small cloth bag that was then swirled in turbid water.11,12
Laboratory testing of the seeds of the M. oleifera
show that the seeds flocculate bacteria by low molecular weight cationic water soluble proteins that attach themselves to suspended particles, including bacteria, and thereby assist in the removal of harmful pathogens from water.11,13–15
Safety tests have shown that doses typically used for water treatment posed no serious threat to human health;16,17
however, few interventions using Moringa
have been tested against bacterial contamination in field trials.13,18
tree grows wild over much of India, and most of the population recognizes it as an ingredient in many sauces, with the colloquial name, “drumstick.” Its effectiveness and acceptability in water decontamination, however, has not yet been assessed in the rural setting in India.
Chlorine is the cornerstone of most municipal water purification systems, and outbreaks have been noted to occur when chlorine has not been regularly administered.19
The Latin American cholera outbreak in 2001 led the Pan American Health Organization (PAHO) and the Centers for Disease Control and Prevention (CDC) to develop the Safe Water System,20
a chlorine-based intervention for in-home decontamination of water. Previous studies on chlorine use in disinfecting water for drinking have showed a marked decrease in coliform counts in beverages using disinfected water and in diarrheal episodes in homes using chlorine in conjunction with health education and designated water storage vessels.21,22
Despite concerns about safety and long-term effects,23
the positive impact of chlorine on preventing disease is undeniable and it remains the cornerstone of the movement for access to clean water around the world. Currently in India, chlorine-based bleaching powders are used for disinfection of most water supply systems on a regular basis.24
Unfortunately, one of the limiting factors in developing effective methods for water decontamination is the acceptability to the population. Chlorine in particular has been noted to be unacceptable to many participants in previous studies.9,25
Freeman and others26
showed that 30% of participants who had tried Klorin (a chlorine-based water treatment, Jet Chemicals Ltd., Kenya) disliked the smell or taste and only 50% of persons who had used chlorine at least once continued to use it. Other studies have shown even lower levels of continued use.27
Given the suboptimal quality of most water available to rural Indian communities, this 6-month randomized, controlled intervention trial aimed to assess the relative efficacy and acceptability of three specific interventions in the rural Indian context: closed valved containers, M. oleifera seeds, and chlorine.