BackgroundThere is evidence that household point-of-use (POU) water treatment products can reduce the enormous burden of water-borne illness. Nevertheless, adoption among the global poor is very low, and little evidence exists on why.MethodsWe gave 600 households in poor communities in Dhaka, Bangladesh randomly-ordered two-month free trials of four water treatment products: dilute liquid chlorine (sodium hypochlorite solution, marketed locally as Water Guard), sodium dichloroisocyanurate tablets (branded as Aquatabs), a combined flocculant-disinfectant powdered mixture (the PUR Purifier of Water), and a silver-coated ceramic siphon filter. Consumers also received education on the dangers of untreated drinking water. We measured which products consumers used with self-reports, observation (for the filter), and chlorine tests (for the other products). We also measured drinking water's contamination with E. coli (compared to 200 control households).FindingsHouseholds reported highest usage of the filter, although no product had even 30% usage. E. coli concentrations in stored drinking water were generally lowest when households had Water Guard. Households that self-reported product usage had large reductions in E. coli concentrations with any product as compared to controls.ConclusionTraditional arguments for the low adoption of POU products focus on affordability, consumers' lack of information about germs and the dangers of unsafe water, and specific products not meshing with a household's preferences. In this study we provided free trials, repeated informational messages explaining the dangers of untreated water, and a variety of product designs. The low usage of all products despite such efforts makes clear that important barriers exist beyond cost, information, and variation among these four product designs. Without a better understanding of the choices and aspirations of the target end-users, household-based water treatment is unlikely to reduce morbidity and mortality substantially in urban Bangladesh and similar populations.

Low-cost point-of-use (POU) safe water products have the potential to reduce waterborne illness, but adoption by the global poor remains low. We performed an eight-month randomized trial of four low-cost household water treatment products in Dhaka, Bangladesh. Intervention households (n = 600) received repeated educational messages about the importance of drinking safe water along with consecutive two-month free trials with each of four POU products in random order. Households randomly assigned to the control group (n = 200) did not receive free products or repeated educational messages. Households' willingness to pay for these products was quite low on average (as measured by bids in an incentive-compatible real-money auction), although a modest share was willing to pay the actual or expected retail price for low-cost chlorine-based products. Furthermore, contrary to our hypotheses that both one's own personal experience and the influence of one's peers would increase consumers' willingness to pay, direct experience significantly decreased mean bids by 18-55% for three of the four products and had no discernible effect on the fourth. Neighbor experience also did not increase bids. Widespread dissemination of safe water products is unlikely until we better understand the preferences and aspirations of these at-risk populations.

Abstract. We conducted a randomized, non-inferiority field trial in urban Dhaka, Bangladesh among mothers to compare microbial efficacy of soapy water (30 g powdered detergent in 1.5 L water) with bar soap and water alone. Fieldworkers collected hand rinse samples before and after the following washing regimens: scrubbing with soapy water for 15 and 30 seconds; scrubbing with bar soap for 15 and 30 seconds; and scrubbing with water alone for 15 seconds. Soapy water and bar soap removed thermotolerant coliforms similarly after washing for 15 seconds (mean log 10 reduction = 0.7 colony-forming units [CFU], P 0.001 for soapy water; mean log 10 reduction = 0.6 CFU, P = 0.001 for bar soap). Increasing scrubbing time to 30 seconds did not improve removal (P 0.05). Scrubbing hands with water alone also reduced thermotolerant coliforms (mean log 10 reduction = 0.3 CFU, P = 0.046) but was less efficacious than scrubbing hands with soapy water. Soapy water is an inexpensive and microbiologically effective cleansing agent to improve handwashing among households with vulnerable children.