Impact on childhood mortality of interventions to improve drinking water, sanitation, and hygiene (WASH) to households: Systematic review and meta-analysis.

BACKGROUND: In low- and middle-income countries (L&MICs), the biggest contributing factors to the global burden of disease in childhood are deaths due to respiratory illness and diarrhoea, both of which are closely related to use of water, sanitation, and hygiene (WASH) services by households. However, current estimates of the health impacts of WASH interventions use self-reported morbidity, which may fail to capture longer-term or more severe impacts. Reported mortality is thought to be less prone to bias than other reported measures. This study aimed to answer the question: What are the impacts of WASH interventions on reported childhood mortality in L&MICs? METHODS AND FINDINGS: We conducted a systematic review and meta-analysis, using a published protocol. Systematic searches of 11 academic databases and trial registries, plus organisational repositories, were undertaken to locate studies of WASH interventions, which were published in peer review journals or other sources (e.g., organisational reports and working papers). Intervention studies of WASH improvements implemented under endemic disease circumstances in L&MICs were eligible, which reported findings at any time until March 2020. We used the participant flow data supplied in response to journal editors' calls for greater transparency. Data were collected by two authors working independently. We included evidence from 24 randomized and 11 nonrandomized studies of WASH interventions from all global regions, incorporating 2,600 deaths. Effects of 48 WASH treatment arms were included in analysis. We critically appraised and synthesised evidence using meta-analysis to improve statistical power. We found WASH interventions are associated with a significant reduction of 17% in the odds of all-cause mortality in childhood (OR = 0.83, 95% CI = 0.74, 0.92, evidence from 38 interventions), and a significant reduction in diarrhoea mortality of 45% (OR = 0.55, 95% CI = 0.35, 0.84; 10 interventions). Further analysis by WASH technology indicated interventions providing improved water in quantity to households were most consistently associated with reductions in all-cause mortality. Community-wide sanitation was most consistently associated with reductions in diarrhoea mortality. Around one-half of the included studies were assessed as being at "moderate risk of bias" in attributing mortality in childhood to the WASH intervention, and no studies were found to be at "low risk of bias." The review should be updated to incorporate additional published and unpublished participant flow data. CONCLUSIONS: The findings are congruent with theories of infectious disease transmission. Washing with water presents a barrier to respiratory illness and diarrhoea, which are the two biggest contributors to all-cause mortality in childhood in L&MICs. Community-wide sanitation halts the spread of diarrhoea. We observed that evidence synthesis can provide new findings, going beyond the underlying data from trials to generate crucial insights for policy. Transparent reporting in trials creates opportunities for research synthesis to answer questions about mortality, which individual studies of interventions cannot be reliably designed to address.

Effects on childhood infections of promoting safe and hygienic complementary-food handling practices through a community-based programme: A cluster randomised controlled trial in a rural area of The Gambia.

BACKGROUND: The Gambia has high rates of under-5 mortality from diarrhoea and pneumonia, peaking during complementary-feeding age. Community-based interventions may reduce complementary-food contamination and disease rates. METHODS AND FINDINGS: A public health intervention using critical control points and motivational drivers, delivered February-April 2015 in The Gambia, was evaluated in a cluster randomised controlled trial at 6- and 32-month follow-up in September-October 2015 and October-December 2017, respectively. After consent for trial participation and baseline data were collected, 30 villages (clusters) were randomly assigned to intervention or control, stratified by population size and geography. The intervention included a community-wide campaign on days 1, 2, 17, and 25, a reminder visit at 5 months, plus informal community-volunteer home visits. It promoted 5 key complementary-food and 1 key drinking-water safety and hygiene behaviours through performing arts, public meetings, and certifications delivered by a team from local health and village structures to all villagers who attended the activities, to which mothers of 6- to 24-month-old children were specifically invited. Control villages received a 1-day campaign on domestic-garden water use. The background characteristics of mother and clusters (villages) were balanced between the trial arms. Outcomes were measured at 6 and 32 months in a random sample of 21-26 mothers per cluster. There were no intervention or research team visits to villages between 6 and 32 months. The primary outcome was a composite outcome of the number of times key complementary-food behaviours were observed as a proportion of the number of opportunities to perform the behaviours during the observation period at 6 months. Secondary outcomes included the rate of each recommended behaviour; microbiological growth from complementary food and drinking water (6 months only); and reported acute respiratory infections, diarrhoea, and diarrhoea hospitalisation. Analysis was by intention-to-treat analysis adjusted by clustering. (Registration: PACTR201410000859336). We found that 394/571 (69%) of mothers with complementary-feeding children in the intervention villages were actively involved in the campaign. No villages withdrew, and there were no changes in the implementation of the intervention. The intervention improved behaviour adoption significantly. For the primary outcome, the rate was 662/4,351(incidence rate [IR] = 0.15) in control villages versus 2,861/4,378 (IR = 0.65) in intervention villages (adjusted incidence rate ratio [aIRR] = 4.44, 95% CI 3.62-5.44, p < 0.001), and at 32 months the aIRR was 1.17 (95% CI 1.07-1.29, p = 0.001). Secondary health outcomes also improved with the intervention: (1) mother-reported diarrhoea at 6 months, with adjusted relative risk (aRR) = 0.39 (95% CI 0.32-0.48, p < 0.001), and at 32 months, with aRR = 0.68 (95% CI 0.48-0.96, p = 0.027); (2) mother-reported diarrhoea hospitalisation at 6 months, with aRR = 0.35 (95% CI 0.19-0.66, p = 0.001), and at 32 months, with aRR = 0.38 (95% CI 0.18-0.80, p = 0.011); and (3) mother-reported acute respiratory tract infections at 6 months, with aRR = 0.67 (95% CI 0.53-0.86, p = 0.001), though at 32 months improvement was not significant (p = 0.200). No adverse events were reported. The main limitations were that only medium to small rural villages were involved. Obtaining laboratory cultures from food at 32 months was not possible, and no stool microorganisms were investigated. CONCLUSIONS: We found that low-cost and culturally embedded behaviour change interventions were acceptable to communities and led to short- and long-term improvements in complementary-food safety and hygiene practices, and reported diarrhoea and acute respiratory tract infections. TRIAL REGISTRATION: The trial was registered on the 17th October 2014 with the Pan African Clinical Trial Registry in South Africa with number (PACTR201410000859336) and 32-month follow-up as an amendment to the trial.

The value of monitoring data in a process evaluation of hygiene behaviour change in Community Health Clubs to explain findings from a cluster-randomised controlled trial in Rwanda.

BACKGROUND: A cluster-Randomised Controlled Trial evaluation of the impact of the Community Health Clubs (CHCs) in the Community Based Environmental Health Promotion Programme in Rwanda in 2015 appeared to find little uptake of 7 hygiene indicators 1 year after the end of the intervention, and low impact on prevention of diarrhoea and stunting. METHODS: Monitoring data was revisited through detailed community records with all the expected inputs, outputs and external determinants analysed for fidelity to the research protocol. Five household inventory observations were taken over a 40-month period including 2 years after the end of the cRCT in a random selection of the 50 intervention CHCs and data compared to that of the trial. Focus Group Discussion with all Environmental Health Officers of the Ministry of Health provided context to understand the long-term community dynamics of hygiene behaviour change. RESULTS: It was found that the intervention had been jeopardised by external determinants with only 54% fidelity to protocol. By the end of the designated intervention period in June 2014, the treatment had reached only 58% of households with 41% average attendance at training sessions by the 4056 registered members and 51% mean completion rate of 20+ sessions. Therefore only 10% of 50 CHCs provided the full so-called 'Classic' training as per-protocol. However, sustainability of the CHCs was high, with all 50 being active 2 years after the end of the cRCT and over 80% uptake of recommended practices of the same 7 key indicators as the trial was achieved by 2017. CONCLUSIONS: The cRCT conclusion that the case study of Rusizi District does not encourage the use of the CHC model for scaling up, raises concerns over the possible misrepresentation of the potential of the holistic CHC model to achieve health impact in a more realistic time frame. It also questions the appropriateness of apparently rigorous quantitative research, such as the cluster-Randomised Controlled Trial as conducted in Rusizi District, to adequately assess community dynamics in complex interventions.

Experiences of capacity strengthening in sanitation and hygiene research in Africa and Asia: the SHARE Research Consortium.

The Sanitation and Hygiene Applied Research for Equity (SHARE) Research Programme consortium is a programme funded by the United Kingdom Department for International Development (DFID) that aims to contribute to achieving universal access to effective, sustainable, and equitable sanitation and hygiene worldwide. The capacity development component is an important pillar for this programme and different strategies were designed and implemented during the various phases of SHARE. This paper describes and reflects on the capacity-building strategies of this large multi-country research consortium, identifying lessons learnt and proposing recommendations for future global health research programmes. In the first phase, the strategy focused on increasing the capacity of individuals and institutions from low- and middle-income countries in conducting their own research. SHARE supported six PhD students and 25 MSc students, and organised a wide range of training events for different stakeholders. SHARE peer-reviewed all proposals that researchers submitted through several rounds of funding and offered external peer-review for all the reports produced under the partner's research platforms. In the second phase, the aim was to support capacity development of a smaller number of African research institutions to move towards their independent sustainability, with a stronger focus on early and mid-career scientists within these institutions. In each institution, a Research Fellow was supported and a specific capacity development plan was jointly developed.Strategies that yielded success were learning by doing (supporting institutions and postgraduate students on sanitation and hygiene research), providing fellowships to appoint mid-career scientists to support personal and institutional development, and supporting tailored capacity-building plans. The key lessons learnt were that research capacity-building programmes need to be driven by local initiatives tailored with support from partners. We recommend that future programmes seeking to strengthen research capacity should consider targeted strategies for individuals at early, middle and later career stages and should be sensitive to other institutional operations to support both the research and management capacities.

Urban Waste Collectors in Belo Horizonte, Brazil: Their Perceptions of Occupational Health Risk.

Frequent contact with hazardous materials makes waste collection a potentially unhealthy activity. This article assesses the perception of waste management workers regarding work-related accidents in domestic and health service contexts in Brazil. Six focus groups were performed between June 2014 and August 2015. The aims of this study were to apprehend different aspects of the participants' health, workers' experiences of work-related accidents and perception of risks. Cuts and puncture injuries were reported most frequently in the line of work and were often considered as irrelevant. Immunization against hepatitis B was not common among all workers, which increases the risk of infection for those individuals. Finally, it is considered urgent to consolidate an inclusive space in which workers can have discussions on their health.

Guinea worm: from Robert Leiper to eradication.

Guinea worm disease, dracunculiasis or dracontiasis, is an ancient disease with records going back over 4500 years, but until the beginning of the 20th century, little was known about its life cycle, particularly how humans became infected. In 1905, Robert Thomas Leiper was sent by the British colonial authorities to West Africa to investigate the spread of Guinea worm disease and to recommend measures to prevent it. While carrying out his investigations, he made important contributions to the aetiology, epidemiology and public health aspects of Guinea worm disease and provided definitive answers to many outstanding questions. First, he tested the validity of previous theories; second, he confirmed the role of water fleas, which he identified as Cyclops, as the intermediate hosts in the life cycle; third, he investigated the development of the parasite in its intermediate host; and fourth, he recommended measures to prevent the disease. [The crustacean Order Cyclopoida in the Family Cyclopidae contains 25 genera, including Cyclops which itself contains over 400 species and may not even be a valid taxon. It is not known how many of these species (or indeed species belonging to related genera) can act as intermediate hosts of Dracunculus medinensis nor do we know which species Fedchenko, Leiper and other workers used in their experiments. It is, therefore, best to use the terms copepod, or copopoid crustacean rather than Cyclops in scientific texts. In this paper, these crustaceans are referred to as copepods except when referring to an original text.] Leiper described the remarkable changes that took place when an infected copepod was placed in a dilute solution of hydrochloric acid; the copepod was immediately killed, but the Dracunculus larvae survived and were released into the surrounding water. From this, he concluded that if a person swallowed an infected copepod, their gastric juice would produce similar results. He next infected monkeys by feeding them copepods infected with Guinea worm larvae, and thus conclusively demonstrated that humans became infected by accidentally ingesting infected crustaceans. Based on these conclusions, he advocated a number of control policies, including avoidance of contaminated drinking water or filtering it, and these preventive measures paved the way for further research. The challenge to eradicate Guinea worm disease was not taken up until about seven decades later since when, with the support of a number of governmental and non-governmental organizations, the number of cases has been reduced from an estimated 3·5 million in 1986 to 25 in 2016 with the expectation that this will eventually lead to the eradication of the disease.

Determinants of quality of shared sanitation facilities in informal settlements: case study of Kisumu, Kenya.

BACKGROUND: Shared facilities are not recognised as improved sanitation due to challenges of maintenance as they easily can be avenues for the spread of diseases. Thus there is need to evaluate the quality of shared facilities, especially in informal settlements, where they are commonly used. A shared facility can be equated to a common good whose management depends on the users. If users do not work collectively towards keeping the facility clean, it is likely that the quality may depreciate due to lack of maintenance. This study examined the quality of shared sanitation facilities and used the common pool resource (CPR) management principles to examine the determinants of shared sanitation quality in the informal settlements of Kisumu, Kenya. METHODS: Using a multiple case study design, the study employed both quantitative and qualitative methods. In both phases, users of shared sanitation facilities were interviewed, while shared sanitation facilities were inspected. Shared sanitation quality was a score which was the dependent variable in a regression analysis. Interviews during the qualitative stage were aimed at understanding management practices of shared sanitation users. Qualitative data was analysed thematically by following the CPR principles. RESULTS: Shared facilities, most of which were dirty, were shared by an average of eight households, and their quality decreased with an increase in the number of households sharing. The effect of numbers on quality is explained by behaviour reflected in the CPR principles, as it was easier to define boundaries of shared facilities when there were fewer users who cooperated towards improving their shared sanitation facility. Other factors, such as defined management systems, cooperation, collective decision making, and social norms, also played a role in influencing the behaviour of users towards keeping shared facilities clean and functional. CONCLUSION: Apart from hardware factors, quality of shared sanitation is largely due to group behaviour of users. The CPR principles form a crucial lens through which the dynamics of shared sanitation facilities in informal settlements can be understood. Development and policy efforts should incorporate group behaviour as they determine the quality of shared sanitation facilities.

Decision-making on shared sanitation in the informal settlements of Kisumu, Kenya.

Unlike most quantitative studies that investigate decision-making on investing in sanitation, this study adopted a qualitative approach to investigate decision-making on shared sanitation in the informal settlements of Kisumu city, in Kenya. Using a grounded theory approach, landlords and tenants were interviewed to identify sanitation decisions, individuals involved in decision-making and factors influencing decision-making. The results indicate that the main sanitation decisions are on investment, emptying, repair and cleaning. Landlords make investment, emptying and repair decisions, while tenants make cleaning decisions. Absentee landlords are less involved in most decision-making compared to live-in landlords, who rarely consult tenants in decision-making. Tenants make decisions after consultations with a third party and often collectively with other tenants. Sanitation interventions in informal settlements should thus, target landlords and tenants, with investment efforts being directed at landlords and maintenance efforts at tenants.

Assessment of work-related accidents associated with waste handling in Belo Horizonte (Brazil).

As more urban solid waste is generated, managing it becomes ever more challenging and the potential impacts on the environment and human health also become greater. Handling waste - including collection, treatment and final disposal - entails risks of work accidents. This article assesses the perception of waste management workers regarding work-related accidents in domestic and health service contexts in Belo Horizonte, Brazil. These perceptions are compared with national data from the Ministry of Social Security on accidents involving workers in solid waste management. A high proportion of accidents involves cuts and puncture injuries; 53.9% among workers exposed to domestic waste and 75% among those exposed to health service waste. Muscular lesions and fractures accounted for 25.7% and 12.5% of accidents, respectively. Data from the Ministry of Social Security diverge from the local survey results, presumably owing to under-reporting, which is frequent in this sector. Greater commitment is needed from managers and supervisory entities to ensure that effective measures are taken to protect workers' health and quality of life. Moreover, workers should defend their right to demand an accurate registry of accidents to complement monitoring performed by health professionals trained in risk identification. This would contribute to the improved recovery of injured workers and would require managers in waste management to prepare effective preventive action.

Monitoring the inputs required to extend and sustain hygiene promotion: findings from the GLAAS 2013/2014 survey.

OBJECTIVES: There are significant gaps in information about the inputs required to effectively extend and sustain hygiene promotion activities to improve people's health outcomes through water, sanitation and hygiene (WASH) interventions. We sought to analyse current country and global trends in the use of key inputs required for effective and sustainable implementation of hygiene promotion to help guide hygiene promotion policy and decision-making after 2015. METHODS: Data collected in response to the GLAAS 2013/2014 survey from 93 countries of 94 were included, and responses were analysed for 12 questions assessing the inputs and enabling environment for hygiene promotion under four thematic areas. Data were included and analysed from 20 External Support Agencies (ESA) of 23 collected through self-administered surveys. RESULTS: Firstly, the data showed a large variation in the way in which hygiene promotion is defined and what constitutes key activities in this area. Secondly, challenges to implement hygiene promotion are considerable: include poor implementation of policies and plans, weak coordination mechanisms, human resource limitations and a lack of available hygiene promotion budget data. CONCLUSION: Despite the proven benefits of hand washing with soap, a critical hygiene-related factor in minimising infection, GLAAS 2013/2014 survey data showed that hygiene promotion remains a neglected component of WASH. Additional research to identify the context-specific strategies and inputs required to enhance the effectiveness of hygiene promotion at scale are needed. Improved data collection methods are also necessary to advance the availability and reliability of hygiene-specific information.

Can water, sanitation and hygiene help eliminate stunting? Current evidence and policy implications.

Stunting is a complex and enduring challenge with far-reaching consequences for those affected and society as a whole. To accelerate progress in eliminating stunting, broader efforts are needed that reach beyond the nutrition sector to tackle the underlying determinants of undernutrition. There is growing interest in how water, sanitation and hygiene (WASH) interventions might support strategies to reduce stunting in high-burden settings, such as South Asia and sub-Saharan Africa. This review article considers two broad questions: (1) can WASH interventions make a significant contribution to reducing the global prevalence of childhood stunting, and (2) how can WASH interventions be delivered to optimize their effect on stunting and accelerate progress? The evidence reviewed suggests that poor WASH conditions have a significant detrimental effect on child growth and development resulting from sustained exposure to enteric pathogens but also due to wider social and economic mechanisms. Realizing the potential of WASH to reduce stunting requires a redoubling of efforts to achieve universal access to these services as envisaged under the Sustainable Development Goals. It may also require new or modified WASH strategies that go beyond the scope of traditional interventions to specifically address exposure pathways in the first 2 years of life when the process of stunting is concentrated.

Seroprevalence of hepatitis B and C among domestic and healthcare waste handlers in Belo Horizonte, Brazil.

Infection with the hepatitis B and C viruses may occur through contact with infected body fluids, including injury with infected sharps. Collectors of domestic or healthcare wastes are potentially exposed to these infections. The aim of this article is to investigate the risk factors associated with the prevalence of hepatitis B and C viruses (HBV and HCV) infection among domestic and healthcare waste workers in Belo Horizonte, Brazil. A cross-sectional study of hepatitis B and C infection was conducted from November 2014 to January 2015, through blood sample collection and interviews about socio-demographic factors with 61 workers exposed to healthcare waste ('exposed') and 461 exposed only to domestic wastes ('unexposed'). The prevalence of antibodies to HCV (Anti-HCV) antibodies was 3.3% in 'exposed' workers and 0.9% in 'unexposed', and of antibody to hepatitis B core antigen (Anti-HBc) was 9.8% and 5.6% in 'exposed' and 'unexposed' workers, respectively. Only 207 (44.9%) of those exposed to domestic waste and 45 (73.8%) of those handling healthcare waste were effectively immunised against hepatitis B virus (HBV). Exposures to domestic waste and to healthcare wastes were associated with similar risks of infection with HBV. The risk of hepatitis C virus (HCV) infection was marginally higher among healthcare waste workers compared with domestic waste workers, probably because of needlestick accidents owing to deficient sharps management systems. Immunisation against hepatitis B and screening tests to ensure the success of vaccination should be a condition for recruitment for both groups of waste workers.

Water supply interruptions and suspected cholera incidence: a time-series regression in the Democratic Republic of the Congo.

BACKGROUND: The eastern provinces of the Democratic Republic of the Congo have been identified as endemic areas for cholera transmission, and despite continuous control efforts, they continue to experience regular cholera outbreaks that occasionally spread to the rest of the country. In a region where access to improved water sources is particularly poor, the question of which improvements in water access should be prioritized to address cholera transmission remains unresolved. This study aimed at investigating the temporal association between water supply interruptions and Cholera Treatment Centre (CTC) admissions in a medium-sized town. METHODS AND FINDINGS: Time-series patterns of daily incidence of suspected cholera cases admitted to the Cholera Treatment Centre in Uvira in South Kivu Province between 2009 and 2014 were examined in relation to the daily variations in volume of water supplied by the town water treatment plant. Quasi-poisson regression and distributed lag nonlinear models up to 12 d were used, adjusting for daily precipitation rates, day of the week, and seasonal variations. A total of 5,745 patients over 5 y of age with acute watery diarrhoea symptoms were admitted to the CTC over the study period of 1,946 d. Following a day without tap water supply, the suspected cholera incidence rate increased on average by 155% over the next 12 d, corresponding to a rate ratio of 2.55 (95% CI: 1.54-4.24), compared to the incidence experienced after a day with optimal production (defined as the 95th percentile-4,794 m3). Suspected cholera cases attributable to a suboptimal tap water supply reached 23.2% of total admissions (95% CI 11.4%-33.2%). Although generally reporting less admissions to the CTC, neighbourhoods with a higher consumption of tap water were more affected by water supply interruptions, with a rate ratio of 3.71 (95% CI: 1.91-7.20) and an attributable fraction of cases of 31.4% (95% CI: 17.3%-42.5%). The analysis did not suggest any association between levels of residual chlorine in the water fed to the distribution network and suspected cholera incidence. Laboratory confirmation of cholera was not available for this analysis. CONCLUSIONS: A clear association is observed between reduced availability of tap water and increased incidence of suspected cholera in the entire town of Uvira in Eastern Democratic Republic of the Congo. Even though access to piped water supplies is low in Uvira, improving the reliability of tap water supply may substantially reduce the incidence of suspected cholera, in particular in neighbourhoods having a higher access to tap water. These results argue in favour of water supply investments that focus on the delivery of a reliable and sustainable water supply, and not only on point-of-use water quality improvements, as is often seen during cholera outbreaks.

Interventions to improve water quality for preventing diarrhoea.

BACKGROUND: Diarrhoea is a major cause of death and disease, especially among young children in low-income countries. In these settings, many infectious agents associated with diarrhoea are spread through water contaminated with faeces.In remote and low-income settings, source-based water quality improvement includes providing protected groundwater (springs, wells, and bore holes), or harvested rainwater as an alternative to surface sources (rivers and lakes). Point-of-use water quality improvement interventions include boiling, chlorination, flocculation, filtration, or solar disinfection, mainly conducted at home. OBJECTIVES: To assess the effectiveness of interventions to improve water quality for preventing diarrhoea. SEARCH METHODS: We searched the Cochrane Infectious Diseases Group Specialized Register (11 November 2014), CENTRAL (the Cochrane Library, 7 November 2014), MEDLINE (1966 to 10 November 2014), EMBASE (1974 to 10 November 2014), and LILACS (1982 to 7 November 2014). We also handsearched relevant conference proceedings, contacted researchers and organizations working in the field, and checked references from identified studies through 11 November 2014. SELECTION CRITERIA: Randomized controlled trials (RCTs), quasi-RCTs, and controlled before-and-after studies (CBA) comparing interventions aimed at improving the microbiological quality of drinking water with no intervention in children and adults. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial quality and extracted data. We used meta-analyses to estimate pooled measures of effect, where appropriate, and investigated potential sources of heterogeneity using subgroup analyses. We assessed the quality of evidence using the GRADE approach. MAIN RESULTS: Forty-five cluster-RCTs, two quasi-RCTs, and eight CBA studies, including over 84,000 participants, met the inclusion criteria. Most included studies were conducted in low- or middle-income countries (LMICs) (50 studies) with unimproved water sources (30 studies) and unimproved or unclear sanitation (34 studies). The primary outcome in most studies was self-reported diarrhoea, which is at high risk of bias due to the lack of blinding in over 80% of the included studies. Source-based water quality improvementsThere is currently insufficient evidence to know if source-based improvements such as protected wells, communal tap stands, or chlorination/filtration of community sources consistently reduce diarrhoea (one cluster-RCT, five CBA studies, very low quality evidence). We found no studies evaluating reliable piped-in water supplies delivered to households. Point-of-use water quality interventionsOn average, distributing water disinfection products for use at the household level may reduce diarrhoea by around one quarter (Home chlorination products: RR 0.77, 95% CI 0.65 to 0.91; 14 trials, 30,746 participants, low quality evidence; flocculation and disinfection sachets: RR 0.69, 95% CI 0.58 to 0.82, four trials, 11,788 participants, moderate quality evidence). However, there was substantial heterogeneity in the size of the effect estimates between individual studies.Point-of-use filtration systems probably reduce diarrhoea by around a half (RR 0.48, 95% CI 0.38 to 0.59, 18 trials, 15,582 participants, moderate quality evidence). Important reductions in diarrhoea episodes were shown with ceramic filters, biosand systems and LifeStraw® filters; (Ceramic: RR 0.39, 95% CI 0.28 to 0.53; eight trials, 5763 participants, moderate quality evidence; Biosand: RR 0.47, 95% CI 0.39 to 0.57; four trials, 5504 participants, moderate quality evidence; LifeStraw®: RR 0.69, 95% CI 0.51 to 0.93; three trials, 3259 participants, low quality evidence). Plumbed in filters have only been evaluated in high-income settings (RR 0.81, 95% CI 0.71 to 0.94, three trials, 1056 participants, fixed effects model).In low-income settings, solar water disinfection (SODIS) by distribution of plastic bottles with instructions to leave filled bottles in direct sunlight for at least six hours before drinking probably reduces diarrhoea by around a third (RR 0.62, 95% CI 0.42 to 0.94; four trials, 3460 participants, moderate quality evidence).In subgroup analyses, larger effects were seen in trials with higher adherence, and trials that provided a safe storage container. In most cases, the reduction in diarrhoea shown in the studies was evident in settings with improved and unimproved water sources and sanitation. AUTHORS' CONCLUSIONS: Interventions that address the microbial contamination of water at the point-of-use may be important interim measures to improve drinking water quality until homes can be reached with safe, reliable, piped-in water connections. The average estimates of effect for each individual point-of-use intervention generally show important effects. Comparisons between these estimates do not provide evidence of superiority of one intervention over another, as such comparisons are confounded by the study setting, design, and population.Further studies assessing the effects of household connections and chlorination at the point of delivery will help improve our knowledge base. As evidence suggests effectiveness improves with adherence, studies assessing programmatic approaches to optimising coverage and long-term utilization of these interventions among vulnerable populations could also help strategies to improve health outcomes.

Assessment of a membrane drinking water filter in an emergency setting.

The performance and acceptability of the Nerox(TM) membrane drinking water filter were evaluated among an internally displaced population in Pakistan. The membrane filter and a control ceramic candle filter were distributed to over 3,000 households. Following a 6-month period, 230 households were visited and filter performance and use were assessed. Only 6% of the visited households still had a functioning filter, and the removal performance ranged from 80 to 93%. High turbidity in source water (irrigation canals), together with high temperatures and large family size were likely to have contributed to poor performance and uptake of the filters.

Integrating surveillance data on water-related diseases and drinking-water quality; action-research in a Brazilian municipality.

The Brazilian Ministry of Health proposed a research study involving municipal professional staff conducting both epidemiological and water quality surveillance to facilitate the integration of the data which they collected. It aimed to improve the intersectoral collaboration and health promotion activities in the municipalities, especially regarding drinking-water quality. We then conducted a study using the action-research approach. At its evaluation phase, a technique which we called 'the tree analogy' was applied in order to identify both possibilities and challenges related to the proposed interlinkage. Results showed that integrating the two data collection systems cannot be attained without prior institutional adjustments. It suggests therefore the necessity to unravel issues that go beyond the selection and the interrelation of indicators and compatibility of software, to include political, administrative and personal matters. The evaluation process led those involved to re-think their practice by sharing experiences encountered in everyday practice, and formulating constructive criticisms. All this inevitably unleashes a process of empowerment. From this perspective, we have certainly gathered some fruit from the Tree, but not necessarily the most visible.

From joint thinking to joint action: a call to action on improving water, sanitation, and hygiene for maternal and newborn health.

Yael Velleman and colleagues argue for stronger integration between the water, sanitation, and hygiene (WASH) and maternal and newborn health sectors. Please see later in the article for the Editors' Summary.

Estimating the impact of unsafe water, sanitation and hygiene on the global burden of disease: evolving and alternative methods.

The 2010 global burden of disease (GBD) study represents the latest effort to estimate the global burden of disease and injuries and the associated risk factors. Like previous GBD studies, this latest iteration reflects a continuing evolution in methods, scope and evidence base. Since the first GBD Study in 1990, the burden of diarrhoeal disease and the burden attributable to inadequate water and sanitation have fallen dramatically. While this is consistent with trends in communicable disease and child mortality, the change in attributable risk is also due to new interpretations of the epidemiological evidence from studies of interventions to improve water quality. To provide context for a series of companion papers proposing alternative assumptions and methods concerning the disease burden and risks from inadequate water, sanitation and hygiene, we summarise evolving methods over previous GBD studies. We also describe an alternative approach using population intervention modelling. We conclude by emphasising the important role of GBD studies and the need to ensure that policy on interventions such as water and sanitation be grounded on methods that are transparent, peer-reviewed and widely accepted.

Assessing the impact of drinking water and sanitation on diarrhoeal disease in low- and middle-income settings: systematic review and meta-regression.

OBJECTIVE: To assess the impact of inadequate water and sanitation on diarrhoeal disease in low- and middle-income settings. METHODS: The search strategy used Cochrane Library, MEDLINE & PubMed, Global Health, Embase and BIOSIS supplemented by screening of reference lists from previously published systematic reviews, to identify studies reporting on interventions examining the effect of drinking water and sanitation improvements in low- and middle-income settings published between 1970 and May 2013. Studies including randomised controlled trials, quasi-randomised trials with control group, observational studies using matching techniques and observational studies with a control group where the intervention was well defined were eligible. Risk of bias was assessed using a modified Ottawa-Newcastle scale. Study results were combined using meta-analysis and meta-regression to derive overall and intervention-specific risk estimates. RESULTS: Of 6819 records identified for drinking water, 61 studies met the inclusion criteria, and of 12,515 records identified for sanitation, 11 studies were included. Overall, improvements in drinking water and sanitation were associated with decreased risks of diarrhoea. Specific improvements, such as the use of water filters, provision of high-quality piped water and sewer connections, were associated with greater reductions in diarrhoea compared with other interventions. CONCLUSIONS: The results show that inadequate water and sanitation are associated with considerable risks of diarrhoeal disease and that there are notable differences in illness reduction according to the type of improved water and sanitation implemented.

Burden of disease from inadequate water, sanitation and hygiene in low- and middle-income settings: a retrospective analysis of data from 145 countries.

OBJECTIVE: To estimate the burden of diarrhoeal diseases from exposure to inadequate water, sanitation and hand hygiene in low- and middle-income settings and provide an overview of the impact on other diseases. METHODS: For estimating the impact of water, sanitation and hygiene on diarrhoea, we selected exposure levels with both sufficient global exposure data and a matching exposure-risk relationship. Global exposure data were estimated for the year 2012, and risk estimates were taken from the most recent systematic analyses. We estimated attributable deaths and disability-adjusted life years (DALYs) by country, age and sex for inadequate water, sanitation and hand hygiene separately, and as a cluster of risk factors. Uncertainty estimates were computed on the basis of uncertainty surrounding exposure estimates and relative risks. RESULTS: In 2012, 502,000 diarrhoea deaths were estimated to be caused by inadequate drinking water and 280,000 deaths by inadequate sanitation. The most likely estimate of disease burden from inadequate hand hygiene amounts to 297,000 deaths. In total, 842,000 diarrhoea deaths are estimated to be caused by this cluster of risk factors, which amounts to 1.5% of the total disease burden and 58% of diarrhoeal diseases. In children under 5 years old, 361,000 deaths could be prevented, representing 5.5% of deaths in that age group. CONCLUSIONS: This estimate confirms the importance of improving water and sanitation in low- and middle-income settings for the prevention of diarrhoeal disease burden. It also underscores the need for better data on exposure and risk reductions that can be achieved with provision of reliable piped water, community sewage with treatment and hand hygiene.