Diarrhea prevention through household-level water disinfection and safe storage in Zambia. An educational intervention for altering water-sanitation behaviors to reduce childhood diarrhea in urban Bangladesh. II. A randomized trial to assess the impact of the intervention on hygienic behaviors and rates of diarrhea. Diarrhoea prevention in Bolivia through point-of-use water treatment and safe storage: a promising new strategy. Combining drinking water treatment and hand washing for diarrhoea prevention, a cluster randomised controlled trial. Community-based hygiene education to reduce diarrhoeal disease in rural Zaire: impact of the intervention on diarrhoeal morbidity. Feasibility and efficacy of in-home water chlorination in rural North-eastern Brazil. Diarrhoea prevention in a high-risk rural Kenyan population through point-of-use chlorination, safe water storage, sanitation, and rainwater harvesting. Delayed effectiveness of home-based interventions in reducing childhood diarrhea, Karachi, Pakistan. Preventing diarrhoea with household ceramic water filters: assessment of a pilot project in Bolivia.
A water quality intervention that consists of water treatment, safe storage, and community education was field tested in Kitwe, Zambia. A total of 166 intervention households were randomly selected from one community and 94 control households from another. Baseline surveys were conducted and the intervention was distributed. Weekly active diarrhea surveillance, biweekly water testing, and a follow-up survey were conducted. Compliance was high in intervention households: 97% reported using disinfectant and 72-95% had measurable chlorine in their water in biweekly testing. The percentage of intervention households storing water safely increased from 41.5% to 89.2%. Stored water in intervention households was significantly less contaminated with Escherichia coli than water in control households (P < 0.001). Diarrheal disease risk for individuals in intervention households was 48% lower than for controls (95% confidence interval = 0.3, 0.9). This intervention is a useful tool for preventing waterborne diseases in families in developing countries who lack access to potable water. An educational intervention was designed to improve three water-sanitation behaviors empirically shown to be associated with high rates of childhood diarrhea in Dhaka, Bangladesh: lack of handwashing before preparing food, open defecation by children in the family compound, and inattention to proper disposal of garbage and feces, increasing the opportunity for young children to place waste products in their mouth. Fifty-one communities, each comprising 38 families, were randomized either to receive (n = 25) or not to receive (n = 26) the intervention. During the six months after the intervention, the rate of diarrhea (per 100 person-weeks) in children under six years of age was 4.3 in the intervention communities and 5.8 in the control communities (26% protective efficacy; p less than 0.0001). A corresponding improvement in handwashing practices before preparing food was noted, although no improvement was observed for defecation and waste disposal practices. These data suggest that educational interventions for water-sanitation practices can have an important beneficial effect upon childhood diarrhea in developing countries, particularly when the interventions are designed in a simple way to promote naturally occurring salutory behaviors that are empirically associated with lower rates of childhood diarrhea. A novel water quality intervention that consists of point-of-use water disinfection, safe storage and community education was field tested in Bolivia. A total of 127 households in two periurban communities were randomized into intervention and control groups, surveyed and the intervention was distributed. Monthly water quality testing and weekly diarrhoea surveillance were conducted. Over a 5-month period, intervention households had 44% fewer diarrhoea episodes than control households (P = 0.002). Infants < 1 year old (P = 0.05) and children 5-14 years old (P = 0.01) in intervention households had significantly less diarrhoea than control children. Campylobacter was less commonly isolated from intervention than control patients (P = 0.02). Stored water in intervention households was less contaminated with Escherichia coli than stored water in control households (P < 0.0001). Intervention households exhibited less E. coli contamination of stored water and less diarrhoea than control households. This promising new strategy may have broad applicability for waterborne disease prevention. To evaluate the effectiveness of point of use water treatment with flocculent-disinfectant on reducing diarrhoea and the additional benefit of promoting hand washing with soap.
                The study was conducted in squatter settlements of Karachi, Pakistan, where diarrhoea is a leading cause of childhood death. Interventions were randomly assigned to 47 neighbourhoods. Households in 10 neighbourhoods received diluted bleach and a water vessel; nine neighbourhoods received soap and were encouraged to wash hands; nine neighbourhoods received flocculent-disinfectant water treatment and a water vessel; 10 neighbourhoods received disinfectant-disinfectant water treatment and soap and were encouraged to wash hands; and nine neighbourhoods were followed as controls. Field workers visited households at least once a week from April to December 2003 to promote use of the interventions and to collect data on diarrhoea.
                Study participants in control neighbourhoods had diarrhoea on 5.2% of days. Compared to controls, participants living in intervention neighbourhoods had a lower prevalence of diarrhoea: 55% (95% CI 17%, 80%) lower in bleach and water vessel neighbourhoods, 51% (95% CI 12%, 76%) lower in hand washing promotion with soap neighbourhoods, 64% lower (95% CI 29%, 90%) in disinfectant-disinfectant neighbourhoods, and 55% (95% CI 18%, 80%) lower in disinfectant-disinfectant plus hand washing with soap neighbourhoods.
                With an intense community-based intervention and supplies provided free of cost, each of the home-based interventions significantly reduced diarrhoea. There was no benefit by combining hand washing promotion with water treatment. Diarrhoeal disease is a leading cause of morbidity in young children in rural Zaire. Few diarrhoea prevention programmes have been implemented in Bandundu Province, where available data suggest an annual prevalence rate of 10%. The urgent need to reduce diarrhoeal morbidity in Zaire, together with the potential effectiveness and feasibility of hygiene education as a diarrhoea prevention strategy, led to the development of the present research project.
                A randomized, controlled trial of an education intervention to reduce diarrhoea through improved personal and domestic hygiene behaviours was conducted in 18 geographically separate village clusters (sites) in rural Zaire. For 12 weeks baseline information on the diarrhoeal morbidity of 2082 children aged 3-35 months was collected at weekly home visits, and structured observations of hygiene practices related to diarrhoea were made on a subset of 300 families. Intervention messages addressed disposal of animal faeces from the yard, handwashing after defecation and before meal preparation and eating, and disposal of children's faeces. Three months after the start of the intervention and exactly 1 year after the baseline studies, a second diarrhoeal morbidity study and a second observational study were conducted in order to evaluate the intervention.
                Children in intervention communities experienced an 11% reduction in the risk of reporting diarrhoea during the peak diarrhoeal season, compared to controls (P < 0.025). The largest differences were seen among children aged 24-35 months, with those from intervention communities reporting significantly fewer episodes, shorter mean durations and hence fewer days of diarrhoea. There was some evidence that greater reductions in diarrhoea occurred in sites where the quality of the intervention, a scored measure of volunteer efficacy and community participation, was highest.
                The results of this study suggest that hygiene education may be an effective approach to reduce the incidence and duration of diarrhoeal episodes in rural Zaire. Children aged 2 years appear to benefit the most. A Hawthorne effect of the education may contribute to diarrhoeal reductions. The purpose of this study was to assess the feasibility, acceptability and effect of an in-home water chlorination programme in a rural village. Previous studies at this site showed high levels of faecal coliforms in household water, high diarrhoea rates in children, and enterotoxigenic Escherichia coli and rotaviruses were the most common pathogens isolated from patients. Household water came from a pond and was stored in clay pots. No homes had sanitary facilities. A blind, cross-over trial of treatment of household water with inexpensive hypochlorite by a community health worker was carried out over 18 weeks among 20 families. Water in the clay pots was sampled serially, and symptom surveillance was done by medical students. The programme was generally acceptable to the villagers and no change in water use patterns were apparent. The mean faecal coliform level in the chlorinated water was significantly less than in the placebo treated samples (70 vs 16000 organisms/dl, P less than 0.001). People living in houses receiving placebo treatment had a mean of 11.2 days of diarrhoea per year, and the highest rate of 36.7 was among children less than 2 years old. Diarrhoea rates were not significantly different among the participants while exposed to water treated with hypochlorite. We conclude that a low-cost programme of this type, which utilizes community resources, is logistically feasible, appears to be culturally acceptable in this setting, and can result in a marked reduction in water contamination. The lack of effect on diarrhoea rates suggests that improvement in water quality may affect morbidity only when other variables relating to faecal-oral agent transmission are ameliorated at the same time. Lack of access to safe water and sanitation contributes to diarrhoea moribidity and mortality in developing countries. We evaluated the impact of household water treatment, latrines, shallow wells, and rainwater harvesting on diarrhoea incidence in rural Kenyan children. We compared diarrhoea rates in 960 children aged <5 years in 556 households in 12 randomly selected intervention villages and six randomly selected comparison villages during weekly home visits over an 8-week period. On multivariate analysis, chlorinating stored water [relative risk (RR) 0.44, 95% confidence interval (CI) 0.28-0.69], latrine presence (RR 0.71, 95% CI 0.54-0.92), rainwater use (RR 0.70, 95% CI 0.52-0.95), and living in an intervention village (RR 0.31, 95% CI 0.23-0.41), were independently associated with lower diarrhoea risk. Diarrhoea risk was higher among shallow well users (RR 1.78, 95% CI 1.12-2.83). Chlorinating stored water, latrines, and rainwater use all decreased diarrhoea risk; combined interventions may have increased health impact. We introduced home drinking water disinfection and handwashing with soap in Karachi squatter settlements to evaluate their effect on diarrhea. In April 2000, 150 households received soap, 76 received dilute bleach and a water storage vessel, and 76 were enrolled as controls. In 2000, among households wealthy enough to own a refrigerator, children in households that received bleach and a vessel had a 73% lower incidence of diarrhea than controls; those that received soap had a 56% lower incidence. There was no reduction in diarrhea in intervention households without a refrigerator. In 2001, households that received bleach and a vessel had a 71% lower incidence of diarrhea and children in households that received soap had a 35% lower incidence than controls. In 2001, the interventions were equally effective in households that had a refrigerator and those that did not. Both of these home-based interventions were ultimately effective in preventing diarrhea, but only households of slightly higher socioeconomic status changed their behavior quickly enough to benefit during the first summer. In an attempt to prevent diarrhoea in a rural community in central Bolivia, an international non-governmental organization implemented a pilot project to improve drinking water quality using gravity-fed, household-based, ceramic water filters. We assessed the performance of the filters by conducting a five-month randomized controlled trial among all 60 households in the pilot community. Water filters eliminated thermotolerant (faecal) coliforms from almost all intervention households and significantly reduced turbidity, thereby improving water aesthetics. Most importantly, the filters were associated with a 45.3% reduction in prevalence of diarrhoea among the study population (p = 0.02). After adjustment for household clustering and repeated episodes in individuals and controlling for age and baseline diarrhoea, prevalence of diarrhoea among the intervention group was 51% lower than controls, though the protective effect was only borderline significant (OR 0.49, 95% CI: 0.24, 1.01; p = 0.05). A follow-up survey conducted approximately 9 months after deployment of the filters found 67% being used regularly, 13% being used intermittently, and 21% not in use. Water samples from all regularly used filters were free of thermotolerant coliforms.
Interventions to improve water quality are generally effective in preventing diarrhoea, and interventions to improve water quality at the household level are more effective than those at the source. Significant heterogeneity among the trials suggests that the actual level of effectiveness may depend on a variety of conditions that research to date cannot fully explain. Rigorous, blinded, multi-arm randomized controlled trials conducted over a longer duration in a variety if settings may help clarify the potential effectiveness.