Effect of in-line drinking water chlorination at the point of collection on child diarrhoea in urban Bangladesh: a double-blind, cluster-randomised controlled trial

BACKGROUND

Previous blinded trials of household water treatment interventions in low-income settings have failed to detect a reduction in child diarrhoea. Technological advances have enabled the development of automated in-line chlorine dosers that can disinfect drinking water without electricity, while also allowing users to continue their typical water collection practices. We aimed to evaluate the effect of installing novel passive chlorination devices at shared water points on child diarrhoea prevalence in low-income, densely populated communities in urban Bangladesh.

METHODS

In this double-blind cluster-randomised controlled trial, 100 shared water points (clusters) in two low-income urban communities in Bangladesh were randomly assigned (1:1) to have their drinking water automatically chlorinated at the point of collection by a solid tablet chlorine doser (intervention group) or to be treated by a visually identical doser that supplied vitamin C (active control group). The trial followed an open cohort design; all children younger than 5 years residing in households accessing enrolled water points were measured every 2-3 months during a 14-month follow-up period (children could migrate into or out of the cluster). The primary outcome was caregiver-reported child diarrhoea (≥3 loose or watery stools in a 24-h period [WHO criteria]) with a 1-week recall, including all available childhood observations in the analyses. This trial is registered with ClinicalTrials.gov, number NCT02606981, and is completed.

FINDINGS

Between July 5, 2015, and Nov 11, 2015, 100 water points with 920 eligible households were enrolled into the study and randomly assigned to the treatment (50 water points; 517 children at baseline; 2073 child observations included in the primary analysis) or control groups (50; 519; 2154). Children in the treatment group had less WHO-defined diarrhoea than did children in the control group (control 216 [10·0%] of 2154; treatment 156 [7·5%] of 2073; prevalence ratio 0·77, 95% CI 0·65-0·91). Drinking water at the point of collection at treatment taps had detectable free chlorine residual 83% (mean 0·37 ppm) of the time compared with 0% at control taps (0·00 ppm).

INTERPRETATION

Passive chlorination at the point of collection could be an effective and scalable strategy in low-income urban settings for reducing child diarrhoea and for achieving global progress towards Sustainable Development Goal 6.1 to attain universal access to safe and affordable drinking water. Targeting a low chlorine residual (<0·5 ppm) in treated water can increase taste acceptability of chlorinated drinking water while still reducing the risk of diarrhoea.

FUNDING

The World Bank.

Urban informal settlements as hotspots of antimicrobial resistance and the need to curb environmental transmission

Antimicrobial resistance (AMR) is a growing public health challenge that is expected to disproportionately burden lower- and middle-income countries (LMICs) in the coming decades. Although the contributions of human and veterinary antibiotic misuse to this crisis are well-recognized, environmental transmission (via water, soil or food contaminated with human and animal faeces) has been given less attention as a global driver of AMR, especially in urban informal settlements in LMICs-commonly known as 'shanty towns' or 'slums'. These settlements may be unique hotspots for environmental AMR transmission given: (1) the high density of humans, livestock and vermin living in close proximity; (2) frequent antibiotic misuse; and (3) insufficient drinking water, drainage and sanitation infrastructure. Here, we highlight the need for strategies to disrupt environmental AMR transmission in urban informal settlements. We propose that water and waste infrastructure improvements tailored to these settings should be evaluated for their effectiveness in limiting environmental AMR dissemination, lowering the community-level burden of antimicrobial-resistant infections and preventing antibiotic misuse. We also suggest that additional research is directed towards developing economic and legal incentives for evaluating and implementing water and waste infrastructure in these settings. Given that almost 90% of urban population growth will occur in regions predicted to be most burdened by the AMR crisis, there is an urgent need to build effective, evidence-based policies that could influence massive investments in the built urban environment in LMICs over the next few decades.

The WASH Benefits and SHINE trials: interpretation of WASH intervention effects on linear growth and diarrhoea

Child stunting is a global problem and is only modestly responsive to dietary interventions. Numerous observational studies have shown that water quality, sanitation, and handwashing (WASH) in a household are strongly associated with linear growth of children living in the same household. We have completed three randomised efficacy trials testing improved household-level WASH with and without improved infant and young child feeding (IYCF) on stunting and diarrhoea in Bangladesh, Kenya, and Zimbabwe. In all trials, improved IYCF had a statistically significant benefit, but WASH had no effect on linear growth. In observational analyses of data from the control groups of the three trials, baseline sanitation was a strong risk factor for stunting in the study populations, suggesting this frequently reported association might be confounded by unmeasured factors of household wellbeing. WASH interventions reduced diarrhoea in Bangladesh, but not in Kenya or Zimbabwe. Intervention promoters visited participants six times per month in Bangladesh compared with monthly in Kenya and Zimbabwe; a review of the literature shows that virtually all published studies that have reported an effect on diarrhoea through home-based water treatment and handwashing promotion achieved high adherence by visiting participants at daily to fortnightly intervals. Despite achieving substantial behavioural change and significant reduction in infection prevalence for some enteric pathogens, detection of enteropathogens among children in the WASH groups of the trials was typically at ten times higher prevalence compared with high-income countries. Considering these results, we recommend that future research in the WASH sector focus on developing and evaluating interventions that are radically more effective in reducing faecal contamination in the domestic environment than the interventions implemented in these trials.

Effect of Sanitation Improvements on Pathogens and Microbial Source Tracking Markers in the Rural Bangladeshi Household Environment

Diarrheal illnesses from enteric pathogens are a leading cause of death in children under five in low- and middle-income countries (LMICs). Sanitation is one way to reduce the spread of enteric pathogens in the environment; however, few studies have investigated the effectiveness of sanitation in rural LMICs in reducing pathogens in the environment. In this study, we measured the impact of a sanitation intervention (dual-pit latrines, sani-scoops, child potties delivered as part of a randomized control trial, WASH Benefits) in rural Bangladeshi household compounds by assessing prevalence ratios, differences, and changes in the concentration of pathogen genes and host-specific fecal markers. We found no difference in the prevalence of pathogenic Escherichia coli, norovirus, or Giardia genes in the domestic environment in the sanitation and control arms. The prevalence of the human fecal marker was lower on child hands and the concentration of animal fecal marker was lower on mother hands in the sanitation arm in adjusted models, but these associations were not significant after correcting for multiple comparisons. In the subset of households with ≥10 individuals per compound, the prevalence of enterotoxigenic E. coli genes on child hands was lower in the sanitation arm. Incomplete removal of child and animal feces or the compound (versus community-wide) scale of intervention could explain the limited impacts of improved sanitation.

Effects of Individual and Combined Water, Sanitation, Handwashing, and Nutritional Interventions on Child Respiratory Infections in Rural Kenya: A Cluster-Randomized Controlled Trial

Poor nutrition and hand hygiene are risk factors for acute respiratory infections (ARIs). Safe drinking water and sanitation can reduce exposure to pathogens and encourage healthy immune responses, reducing the risk of ARIs. Within a trial assessing impacts of water, sanitation, and handwashing (WASH), and nutritional interventions, we evaluated effects on ARIs. The WASH Benefits cluster-randomized trial enrolled pregnant women from Kenyan villages and evaluated health outcomes in children born to enrolled mothers 1 and 2 years after intervention delivery. Geographically adjacent clusters were block-randomized into a passive control (no promotional visits), a double-sized active control (monthly visits to measure mid–upper arm circumference), and six intervention groups: chlorinated drinking water (W), improved sanitation (S), handwashing with soap (H), combined WSH, improved nutrition (N) through counseling and lipid-based nutrient supplementation (LNS), and combined WSHN. The main outcome was the prevalence of ARI symptoms (cough, panting, wheezing, or difficulty breathing) in children younger than 3 years. Masking participants was not possible. Analyses were intention-to-treat. Between November 2012 and May 2014, 702 clusters were enrolled, including 6,960 (year 1) and 7,088 (year 2) children with ARI data. The cluster-level intra-cluster correlation coefficient for ARIs was 0.026 across both years. Water, sanitation, and handwashing interventions with behavior change messaging did not reduce ARIs. Nutrition counseling and LNS modestly reduced ARI symptoms compared with controls in year 1 [prevalence ratio (PR): 0.87, 95% confidence interval (CI): 0.77–0.99], but no effect in the combined WSHN group weakens this finding.

Ruminant Fecal Contamination of Drinking Water Introduced Post-Collection in Rural Kenyan Households

In sub-Saharan Africa, many families travel to collect water and store it in their homes for daily use, presenting an opportunity for the introduction of fecal contamination. One stored and one source water sample were each collected from 45 households in rural Kenya. All 90 samples were analyzed for fecal indicator bacteria (E. coli and enterococci) and species-specific contamination using molecular microbial source tracking assays. Human (HF183), avian (GFD), and ruminant (BacR) contamination were detected in 52, two, and four samples, respectively. Stored water samples had elevated enterococci concentrations (p < 0.01, Wilcoxon matched pairs test) and more frequent BacR detection (89% versus 27%, p < 0.01, McNemar's exact test) relative to source water samples. fsQCA (fuzzy set qualitative comparative analysis) was conducted on the subset of households with no source water BacR contamination to highlight combinations of factors associated with the introduction of BacR contamination to stored water supplies. Three combinations were identified: (i) ruminants in the compound, safe water extraction methods, and long storage time, (ii) ruminants, unsafe water extraction methods, and no soap at the household handwashing station, and (iii) long storage time and no soap. This suggests that multiple pathways contribute to the transmission of ruminant fecal contamination in this context, which would have been missed if data were analyzed using standard regression techniques.

Effect of Neighborhood Sanitation Coverage on Fecal Contamination of the Household Environment in Rural Bangladesh

Enteric pathogens can be transmitted within the household and the surrounding neighborhood. The objective of this study was to understand the effect of neighborhood-level sanitation coverage on contamination of the household environment with levels of fecal indicator bacteria in rural Bangladesh. We conducted spot-check observations of sanitation facilities in neighboring households (NHs) within a 20-m radius of target households with children aged 6-24 months. Sanitation facilities were defined as improved (a private pit latrine with a slab or better) or unimproved. Fecal coliforms (FCs) on children's hands and sentinel toy balls were measured and used as indicators of household-level fecal contamination. We visited 1,784 NHs surrounding 428 target households. On average, sentinel toy balls had 2.11(standard deviation [SD] = 1.37) log₁₀ colony-forming units (CFUs) of FCs/toy ball and children's hands had 2.23 (SD = 1.15) log₁₀ CFU of FCs/two hands. Access to 100% private improved sanitation coverage in the neighborhood was associated with a small and statistically insignificant difference in contamination of sentinel toy balls (difference in means = -0.13 log₁₀ CFU/toy ball; 95% confidence intervals [CI]: -0.64, 0.39; P = 0.63) and children's hands (difference in means = -0.11 log₁₀ CFU/two hands; 95% CI: -0.53, 0.32; P = 0.62). Improved sanitation coverage in the neighborhood had limited measurable effect on FCs in the target household environment. Other factors such as access to improved sanitation in the household, absence of cow dung, presence of appropriate water drainage, and optimal handwashing practice may be more important in reducing FCs in the household environment.

Age-related changes to environmental exposure: variation in the frequency that young children place hands and objects in their mouths

Children are exposed to environmental contaminants through direct ingestion of water, food, soil, and feces, and through indirect ingestion owing to mouthing hands and objects. We quantified ingestion among 30 rural Bangladeshi children < 4 years old, recording every item touched or mouthed during 6-hour video observations that occurred annually for 3 years. We calculated the frequency and duration of mouthing and the prevalence of mouth contacts with soil and feces. We compared the mouthing frequency distributions to those from US children to evaluate the appropriateness of applying the US data to the Bangladeshi context. Median hand-mouthing frequency was 43-72 times/h and object-mouthing frequency 17-34 times/h among the five age groups assessed. For half of the observations, > 75% of all hand mouthing was associated with eating. The frequency of indoor hand mouthing not related to eating was similar to the frequency of all indoor hand mouthing among children in the United States. Object-mouthing frequency was higher among Bangladeshi children compared with US children. There was low intra-child correlation of mouthing frequencies over our longitudinal visits. Our results suggest that children's hand- and object-mouthing vary by geography and culture and that future exposure assessments can be cross-sectional if the goal is to estimate population-level distributions of mouthing frequencies. Of all observations, a child consumed soil in 23% and feces in 1%.

Microbiological contamination of young children's hands in rural Bangladesh: Associations with child age and observed hand cleanliness as proxy

Background

Hands are a route of transmission for fecal-oral pathogens. This analysis aimed to assess associations between hand E. coli contamination and child age and determine if observed hand cleanliness can serve as a proxy for E. coli contamination on young children’s hands.

Methods

Trained field workers collected hand rinse samples from children aged 1–14 months in 584 households in rural Bangladesh and assessed the visual cleanliness of child hands (fingernails, finger pads and palms). Samples were analyzed using the IDEXX most probable number (MPN) methodto enumerate E. coli. We assessed if child age (immobile children aged 1–4 months vs. mobile children aged 5–14 months) is associated with log₁₀E. coli counts on hands using generalized estimating equations (GEE). We estimated the log₁₀ difference in hand E. coli counts associated with the cleanliness of different hand parts using a multivariable GEE model.We calculated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for dirty fingernails, fingerpads, palms and overall hands (the three observed parts combined) against binary E. coli presence on hands.

Results

E. coli was detected on 43% of child hands. Children in the mobile age range had 0.17 log₁₀ MPN higher E. coli on hands than those in the immobile age range (Δlog₁₀ = 0.17, 95% CI = 0.02, 0.32, p = 0.03). Children with visible dirt particles on finger pads had 0.46 log₁₀ MPN higher E. coli on hands than those with clean finger pads (Δlog₁₀ = 0.46, 95% CI = 0.05, 0.87, p = 0.03). Dirty fingernails indicated binary E. coli presence with 81% sensitivity and 26% specificity while dirty fingerpads and palms indicated E. coli presence with 29% sensitivity and 75–77% specificity. The PPV was 45–48% and NPV 59–65% for all three types of observations.

Conclusion

Hand contamination with E. coli was prevalent among young children in rural Bangladesh, with higher levels of contamination among mobile children. Studies should assess if strategies to remove animal feces from the courtyard, provide designated hygienic play spaces for children and deliver targeted messaging to mothers to wipe or wash children’s hands after contact with animals and animal feces reduce child hand contamination. Visible hand cleanliness was a poor predictor of E. coli presence on young children’s hands so other low-cost field measurements are needed to accurately detect fecal contamination on hands.

Predictors of Enteric Pathogens in the Domestic Environment from Human and Animal Sources in Rural Bangladesh

Fecal indicator organisms are measured to indicate the presence of fecal pollution, yet the association between indicators and pathogens varies by context. The goal of this study was to empirically evaluate the relationships between indicator Escherichia coli, microbial source tracking markers, select enteric pathogen genes, and potential sources of enteric pathogens in 600 rural Bangladeshi households. We measured indicators and pathogen genes in stored drinking water, soil, and on mother and child hands. Additionally, survey and observational data on sanitation and domestic hygiene practices were collected. Log10 concentrations of indicator E. coli were positively associated with the prevalence of pathogenic E. coli genes in all sample types. Given the current need to rely on indicators to assess fecal contamination in the field, it is significant that in this study context indicator E. coli concentrations, measured by IDEXX Colilert-18, provided quantitative information on the presence of pathogenic E. coli in different sample types. There were no significant associations between the human fecal marker (HumM2) and human-specific pathogens in any environmental sample type. There was an increase in the prevalence of Giardia lamblia genes, any E. coli virulence gene, and the specific E. coli virulence genes stx1/2 with every log10 increase in the concentration of the animal fecal marker (BacCow) on mothers' hands. Thus, domestic animals were important contributors to enteric pathogens in these households.

The implications of three major new trials for the effect of water, sanitation and hygiene on childhood diarrhea and stunting: a consensus statement

BACKGROUND

Three large new trials of unprecedented scale and cost, which included novel factorial designs, have found no effect of basic water, sanitation and hygiene (WASH) interventions on childhood stunting, and only mixed effects on childhood diarrhea. Arriving at the inception of the United Nations' Sustainable Development Goals, and the bold new target of safely managed water, sanitation and hygiene for all by 2030, these results warrant the attention of researchers, policy-makers and practitioners.

MAIN BODY

Here we report the conclusions of an expert meeting convened by the World Health Organization and the Bill and Melinda Gates Foundation to discuss these findings, and present five key consensus messages as a basis for wider discussion and debate in the WASH and nutrition sectors. We judge these trials to have high internal validity, constituting good evidence that these specific interventions had no effect on childhood linear growth, and mixed effects on childhood diarrhea. These results suggest that, in settings such as these, more comprehensive or ambitious WASH interventions may be needed to achieve a major impact on child health.

CONCLUSION

These results are important because such basic interventions are often deployed in low-income rural settings with the expectation of improving child health, although this is rarely the sole justification. Our view is that these three new trials do not show that WASH in general cannot influence child linear growth, but they do demonstrate that these specific interventions had no influence in settings where stunting remains an important public health challenge. We support a call for transformative WASH, in so much as it encapsulates the guiding principle that - in any context - a comprehensive package of WASH interventions is needed that is tailored to address the local exposure landscape and enteric disease burden.

Effect of an equipment-behavior change intervention on handwashing behavior among primary school children in Kenya: the Povu Poa school pilot study

BACKGROUND

Handwashing prevalence in schools in Kenya is low due to lack of access to water and soap and lack of drive for handwashing. Soapy water made from detergent powder is an inexpensive alternative to bar soap and disgust and social norms change can be powerful drivers of handwashing, but their effectiveness has not been assessed in school setting. In Kenyan public schools, we evaluated an equipment-behavior change intervention's effect on handwashing outcomes. We also monitored functionality of the Povu Poa prototypes to identify design improvements necessary for continued high usage in institutional settings.

METHODS

The intervention included the "Povu Poa", a new type of handwashing station that dispensed foaming soap and rinse water, combined with school-wide behavior change promotion based on disgust and social norms. In this stepped-wedge cluster-randomized trial, we randomly selected 30 schools and divided them into 3 groups of 10. Following baseline data collection, we delivered the intervention sequentially (Group 1: 3-5 weeks after baseline; Group 2: 6-8 weeks; Group 3: 19-24 weeks). We observed outcomes [1] availability of handwashing materials at handwashing places, and; 2) observed handwashing behavior after toilet use among schoolchildren) at baseline and in three follow-up rounds. We compared the outcomes between schools that had received the intervention and schools that had not yet received the intervention.

RESULTS

Water and soap/soapy water were available at 2% of school visits before intervention, and at 42% of school visits after intervention.. Before intervention, we observed handwashing with water after 11% of 461 toilet use events; no one was observed to wash hands with soap/soapy water. After intervention, we observed handwashing after 62% of 383 toilet use events (PR = 5.96, 95% CI = 3.02, 11.76) and handwashing with soap/soapy water after 26% of events (PR incalculable). Foaming soap dispenser caps were cracked in 31% of all observations, but were typically still functional.

CONCLUSIONS

Our combined equipment-behavior intervention increased availability of handwashing materials and improved the compliance with handwashing after using the toilet, but handwashing with soap was still rare. Equipment durability must be improved for deployment in schools at scale. American Economic Association's Registry for Randomized Controlled Trials; Trial Registry Number (TRN): AEARCTR-0000662; Date of Registry: April 14, 2015.

The role of water, sanitation and hygiene interventions in reducing soil-transmitted helminths: interpreting the evidence and identifying next steps

The transmission soil transmitted helminths (STH) occurs via ingestion of or contact with infective stages present in soil contaminated with human faeces. It follows therefore that efforts to reduce faecal contamination of the environment should help to reduce risk of parasite exposure and improvements in water, sanitation and hygiene (WASH) are seen as essential for the long-term, sustainable control of STH. However, the link between WASH and STH is not always supported by the available evidence from randomised controlled trials, which report mixed effects of WASH intervention on infection risk. This review critically summarises the available trial evidence and offers an interpretation of the observed heterogeneity in findings. The review also discusses the implications of findings for control programmes and highlights three main issues which merit further consideration: intervention design, exposure assessment, and intervention fidelity assessment.

Comparison of analytical techniques to explain variability in stored drinking water quality and microbial hand contamination of female caregivers in Tanzania

Exposure to fecal contamination continues to be a major public health concern for low-income households in sub-Saharan Africa. Drinking water and hands are known transmission routes for pathogens in household environments. In an effort to identify explanatory variables of water and hand contamination, a variety of analytical approaches have been employed that model variation in E. coli contamination as a function of behaviors and household characteristics. Using data collected from 1217 households in Bagamoyo, Tanzania, this investigation compares the explanatory variables identified in the three different modeling methods to explain hand and water contamination: ordinary least squares regression, logistic regression, and classification tree. Although the modeling approaches varied, there were some similarities in the results, with certain explanatory variables being consistently identified as being related to hand and water contamination (e.g., water source type for the water models and activity prior to sampling for the hand models). At the same time, there were also marked differences across the models. In sum, these results suggest there are benefits to using multiple analysis methods to assess relationships in complex systems. The models were also characterized by low explanatory power, suggesting that variation in hand and water contamination is difficult to capture when analyzing one-time water and hand rinse samples. For improved model performance, future studies could explore modeling of repeat measures of water quality and hand contamination.

Effect of a sanitation intervention on soil-transmitted helminth prevalence and concentration in household soil: A cluster-randomized controlled trial and risk factor analysis

Improved sanitation has been associated with a reduced prevalence of soil-transmitted helminth (STH) infection and has been hypothesized to prevent fecal contamination from spreading throughout the household environment. We evaluated the effect of providing households with a pit latrine with a plastic slab and drophole cover, child feces management tools, and associated behavioral messaging on reducing STH eggs in household soil. We collected soil samples from 2107 households (898 control and 1209 improved sanitation intervention households) that were enrolled in the WASH Benefits cluster randomized controlled trial in rural Kenya and performed a post-intervention analysis after two years of intervention exposure. Following a pre-specified analysis plan, we combined all households that received the sanitation intervention into one group for comparison to control households. The prevalence of STH eggs in soil was 18.9% in control households and 17.0% in intervention households. The unadjusted prevalence ratio of total STH eggs in the intervention groups compared to the control group was 0.94 (95% CI: 0.78-1.13). The geometric mean concentration was 0.05 eggs/g dry soil in control households and intervention households. Unadjusted and adjusted models gave similar results. We found use of a shared latrine, presence of a roof over the sampling area, and the number of dogs owned at baseline was associated with an increased prevalence of STH eggs in soil; the presence of a latrine that was at least 2 years old and a latrine with a covered drophole was associated with a reduction in the prevalence of STH eggs in soil. Soil moisture content was also associated with an increased prevalence of STH eggs in soil. Our results indicate that an intervention designed to increase access to improved latrines and child feces management tools may not be enough to impact environmental occurrence of STH in endemic areas where latrine coverage is already high.

Effects of lipid-based nutrient supplements and infant and young child feeding counseling with or without improved water, sanitation, and hygiene (WASH) on anemia and micronutrient status: results from 2 cluster-randomized trials in Kenya and Bangladesh

Background

Anemia in young children is a global health problem. Risk factors include poor nutrient intake and poor water quality, sanitation, or hygiene.

Objective

We evaluated the effects of water quality, sanitation, handwashing, and nutrition interventions on micronutrient status and anemia among children in rural Kenya and Bangladesh.

Design

We nested substudies within 2 cluster-randomized controlled trials enrolling pregnant women and following their children for 2 y. These substudies included 4 groups: water, sanitation, and handwashing (WSH); nutrition (N), including lipid-based nutrient supplements (LNSs; ages 6-24 mo) and infant and young child feeding (IYCF) counseling; WSH+N; and control. Hemoglobin and micronutrient biomarkers were measured after 2 y of intervention and compared between groups using generalized linear models with robust SEs.

Results

In Kenya, 699 children were assessed at a mean ± SD age of 22.1 ± 1.8 mo, and in Bangladesh 1470 participants were measured at a mean ± SD age of 28.0 ± 1.9 mo. The control group anemia prevalences were 48.8% in Kenya and 17.4% in Bangladesh. There was a lower prevalence of anemia in the 2 N intervention groups in both Kenya [N: 36.2%; prevalence ratio (PR): 0.74; 95% CI: 0.58, 0.94; WSH+N: 27.3%; PR: 0.56; 95% CI: 0.42, 0.75] and Bangladesh (N: 8.7%; PR: 0.50; 95% CI: 0.32, 0.78; WSH+N: 7.9%, PR: 0.46; 95% CI: 0.29, 0.73). In both trials, the 2 N groups also had significantly lower prevalences of iron deficiency, iron deficiency anemia, and low vitamin B-12 and, in Kenya, a lower prevalence of folate and vitamin A deficiencies. In Bangladesh, the WSH group had a lower prevalence of anemia (12.8%; PR: 0.74; 95% CI: 0.54, 1.00) than the control group, whereas in Kenya, the WSH+N group had a lower prevalence of anemia than did the N group (PR: 0.75; 95% CI: 0.53, 1.07), but this was not significant (P = 0.102).

Conclusions

IYCF counseling with LNSs reduced the risks of anemia, iron deficiency, and low vitamin B-12. Effects on folate and vitamin A varied between studies. Improvements in WSH also reduced the risk of anemia in Bangladesh but did not provide added benefit over the nutrition-specific intervention. These trials were registered at clinicaltrials.gov as NCT01590095 (Bangladesh) and NCT01704105 (Kenya).

Sickle Cell and α+-Thalassemia Traits Influence the Association between Ferritin and Hepcidin in Rural Kenyan Children Aged 14-26 Months

Background

The relation between subclinical hemoglobinopathies and concentrations of the iron-regulatory hormone hepcidin is not well characterized.

Objective

We investigated the relation of hepcidin concentration with hemoglobinopathies among young children in Kenya.

Methods

We quantified serum hepcidin and ferritin in 435 Kenyan children aged 14-20 mo in a subsample of the Water, Sanitation, and Handwashing (WASH) Benefits Trial. Blood samples were genotyped for α+-thalassemia and for sickle cell disorder. Hepcidin was compared across sickle cell and α+-thalassemia genotypes separately by using generalized linear models, and children who were normozygous for both conditions were also compared with those who had either of these conditions. In the association between hepcidin and ferritin, we assessed effect modification by genotype.

Results

In this population, we found that 16.2% had sickle cell trait and 0.2% had sickle cell disorder, whereas 40.0% were heterozygous for α+-thalassemia and 8.2% were homozygous. Hepcidin concentration did not differ by genotype, but effect modification was found by genotype in the association between hepcidin and ferritin (P < 0.1). Among normozygous sickle cell children (HbAA), there was an association between hepcidin and ferritin (β = 0.92; 95% CI: 0.72, 1.10). However, among those with sickle cell trait (HbAS), the association was no longer significant (β = 0.31; 95% CI: -0.04, 0.66). Similarly, among children who were normozygous (αα/αα) or heterozygous (-α/αα) for α+-thalassemia, hepcidin and ferritin were significantly associated [β = 0.94 (95% CI: 0.68, 1.20) and β = 0.77 (95% CI: 0.51, 1.03), respectively]; however, in children who were homozygous for α+-thalassemia (-α/-α), there was no longer a significant association (β = 0.45; 95% CI: -0.10, 1.00).

Conclusion

Hepcidin was not associated with hemoglobin genotype, but there may be a difference in the way hepcidin responds to iron status among those with either sickle cell trait or homozygous α+-thalassemia in young Kenyan children. This trial was registered at clinicaltrials.gov as NCT01704105.

Do Sanitation Improvements Reduce Fecal Contamination of Water, Hands, Food, Soil, and Flies? Evidence from a Cluster-Randomized Controlled Trial in Rural Bangladesh

Sanitation improvements have had limited effectiveness in reducing the spread of fecal pathogens into the environment. We conducted environmental measurements within a randomized controlled trial in Bangladesh that implemented individual and combined water treatment, sanitation, handwashing (WSH) and nutrition interventions (WASH Benefits, NCT01590095). Following approximately 4 months of intervention, we enrolled households in the trial's control, sanitation and combined WSH arms to assess whether sanitation improvements, alone and coupled with water treatment and handwashing, reduce fecal contamination in the domestic environment. We quantified fecal indicator bacteria in samples of drinking and ambient waters, child hands, food given to young children, courtyard soil and flies. In the WSH arm, Escherichia coli prevalence in stored drinking water was reduced by 62% (prevalence ratio = 0.38 (0.32, 0.44)) and E. coli concentration by 1-log (Δlog10 = -0.88 (-1.01, -0.75)). The interventions did not reduce E. coli along other sampled pathways. Ambient contamination remained high among intervention households. Potential reasons include noncommunity-level sanitation coverage, child open defecation, animal fecal sources, or naturalized E. coli in the environment. Future studies should explore potential threshold effects of different levels of community sanitation coverage on environmental contamination.

A behaviour change intervention with lipid-based nutrient supplements had little impact on young child feeding indicators in rural Kenya

Poor infant and young child feeding (IYCF) practices are associated with linear growth faltering. Our objective was to evaluate the impact of a nutrition and water and sanitation for health intervention on three IYCF indicators-minimum dietary diversity (MDD), minimum meal frequency (MMF), and minimum acceptable diet (MAD) in Kenyan children. Households were randomized into one of eight groups: (a) active control; (b) passive control; (c) water quality (W); (d) sanitation (S); (e) handwashing (H); (f) combined Water, Sanitation, and Handwashing; (g) nutrition (N); and (h) combined WSH + N. In the N and WSH + N arms, community-based promoters counselled households on optimal IYCF practices, and small-quantity lipid-based nutrient supplements (SQ-LNS) were provided to children 6-24 months of age. Twelve months (Year 1) and 24 months (Year 2) after interventions began, enumerators surveyed mothers to ascertain IYCF practices. We made pairwise comparisons of each intervention arm versus the active control arm using log binomial models. In total, 3,652 caretakers were surveyed at Year 1 and 4,987 caretakers at Year 2. Compared with the active control, there were no differences in any of the arms in MDD, MMF, or MAD, aside from an increase in MDD at Year 1 in the nutrition only arm but not in the combined WSH + N arm (N: 68%; WSH + N: 61%; C: 61%; N arm prevalence ratio: 1.13 95% CI [1.01, 1.25]). In this setting, a nutrition behaviour change communication intervention had little impact on IYCF indicators. The provision of SQ-LNS was not detrimental to current IYCF indicators in the community.

Fecal Indicator Bacteria along Multiple Environmental Transmission Pathways (Water, Hands, Food, Soil, Flies) and Subsequent Child Diarrhea in Rural Bangladesh

Enteric pathogens can be transmitted through multiple environmental pathways, yet little is known about the relative contribution of each pathway to diarrhea risk among children. We aimed to identify fecal transmission pathways in the household environment associated with prospectively measured child diarrhea in rural Bangladesh. We measured the presence and levels of Escherichia coli in tube wells, stored drinking water, pond water, child hand rinses, courtyard soil, flies, and food in 1843 households. Gastrointestinal symptoms among children ages 0-60 months were recorded concurrently at the time of environmental sample collection and again a median of 6 days later. Incident diarrhea (3 or more loose stools in a 24-h period) was positively associated with the concentration of E. coli on child hands measured on the first visit (incidence rate ratio [IRR] = 1.23, 95% CI 1.06, 1.43 for a log₁₀ increase), while other pathways were not associated. In cross-sectional analysis, there were no associations between concurrently measured environmental contamination and diarrhea. Our findings suggest higher levels of E. coli on child hands are strongly associated with subsequent diarrheal illness rates among children in rural Bangladesh.

Effects of water quality, sanitation, handwashing, and nutritional interventions on child development in rural Kenya (WASH Benefits Kenya): a cluster-randomised controlled trial

Background

Poor nutrition and infectious diseases can prevent children from reaching their developmental potential. We aimed to assess the effects of improvements in water, sanitation, handwashing, and nutrition on early child development in rural Kenya.

Methods

In this cluster-randomised controlled trial, we enrolled pregnant women in their second or third trimester from three counties (Kakamega, Bungoma, and Vihiga) in Kenya's western region, with an average of 12 households per cluster. Groups of nine geographically adjacent clusters were block-randomised, using a random number generator, into the six intervention groups (including monthly visits to promote target behaviours), a passive control group (no visits), or a double-sized active control group (monthly household visits to measure child mid-upper arm circumference). The six intervention groups were: chlorinated drinking water; improved sanitation; handwashing with soap; combined water, sanitation, and handwashing; improved nutrition through counselling and provision of lipid-based nutrient supplements; and combined water, sanitation, handwashing, and nutrition. Here we report on the prespecified secondary child development outcomes: gross motor milestone achievement assessed with the WHO module at year 1, and communication, gross motor, personal social, and combined scores measured by the Extended Ages and Stages Questionnaire (EASQ) at year 2. Masking of participants was not possible, but data assessors were masked. Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01704105.

Findings

Between Nov 27, 2012, and May 21, 2014, 8246 women residing in 702 clusters were enrolled. No clusters were lost to follow-up, but 2212 households with 2279 children were lost to follow-up by year 2. 5791 (69%) children were measured at year 1 and 6107 (73%) at year 2. At year 1, compared with the active control group, the combined water, sanitation, handwashing, and nutrition group had greater rates of attaining the standing with assistance milestone (hazard ratio 1·23, 95% CI 1·09-1·40) and the walking with assistance milestone (1·32, 1·17-1·50), and the handwashing group had a greater rate of attaining the standing alone milestone (1·15, 1·01-1·31). There were no differences when comparing the other intervention groups with the active control group on any of the motor milestone measures at year 1. At year 2, there were no differences among groups for the communication, gross motor, personal social, or combined EASQ scores.

Interpretation

The handwashing and combined water, sanitation, handwashing, and nutrition interventions might have improved child motor development after 1 year, although after 2 years there were no other differences between groups. Future research should examine ways to make community health and nutrition programmes more effective at supporting child development.

Funding

Bill & Melinda Gates Foundation.

A Cross Sectional Study of the Association between Sanitation Type and Fecal Contamination of the Household Environment in Rural Bangladesh

We conducted a cross sectional study to assess 1) the association between access to basic sanitation and fecal contamination of sentinel toy balls and 2) if other sanitation factors such as shared use and cleanliness are associated with fecal contamination of sentinel toy balls. We assessed sanitation facilities in 454 households with a child aged 6-24 months in rural Bangladesh. We defined "basic" sanitation as access to improved sanitation facilities (pit latrine with a slab or better) not shared with other households. In each household, an identical toy ball was given to the target child. After 24 hours, the balls were rinsed to enumerate fecal coliforms as an indicator of household fecal contamination. Households with basic sanitation had lower fecal coliform contamination than households with no access to basic sanitation (adjusted difference in means: -0.31 log₁₀ colony forming units [CFU]/toy ball; 95% confidence interval [CI]: -0.61, -0.01). Shared sanitation facilities of otherwise improved type were more likely to have visible feces on the latrine slab compared with private facilities. Among households with access to improved sanitation, households with no visible feces on the latrine slab had less toy ball contamination than households with visible feces on the latrine slab (adjusted difference in means: -0.38 log₁₀ CFU/toy ball; 95% CI: -0.77, 0.02). Access to basic sanitation may prevent fecal contamination of the household environment. An Improved sanitation facility used by an individual household may be better in preventing household fecal contamination compared with improved facilities shared with other households.

Prevalence and Association of Escherichia coli and Diarrheagenic Escherichia coli in Stored Foods for Young Children and Flies Caught in the Same Households in Rural Bangladesh

Consumption of contaminated stored food can cause childhood diarrhea. Flies carry enteropathogens, although their contribution to food contamination remains unclear. We investigated the role of flies in contaminating stored food by collecting food and flies from the same households in rural Bangladesh. We selected 182 households with children ≤ 24 months old that had stored foods for later feeding at room temperature for ≥ 3 hours. We collected food samples and captured flies with fly tapes hung by the kitchen. We used the IDEXX Quanti-Tray System (Colilert-18 media; IDEXX Laboratories, Inc., Westbrook, ME) to enumerate Escherichia coli with the most probable number (MPN) method. Escherichia coli–positive IDEXX wells were analyzed by polymerase chain reaction for pathogenic E. coli genes (eae, ial, bfp, ipaH, st, lt, aat, aaiC, stx₁, and stx₂). Escherichia coli was detected in 61% (111/182) of food samples, with a mean of 1.1 log₁₀ MPN/dry g. Fifteen samples (8%) contained pathogenic E. coli; seven (4%) had enteropathogenic E. coli (EPEC) genes (eae and/or bfp); and 10 (5%) had enteroaggregative E. coli genes (aat and/or aaiC). Of flies captured in 68 (37%) households, E. coli was detected in 41 (60%, mean 2.9 log₁₀ MPN/fly), and one fly (1%) had an EPEC gene (eae). For paired fly-food samples, each log₁₀ MPN E. coli increase in flies was associated with a 0.31 log₁₀ MPN E. coli increase in stored food (95% confidence interval: 0.07, 0.55). In rural Bangladesh, flies possibly a likely route for fecal contamination of stored food. Controlling fly populations may reduce contamination of food stored for young children.