Effect of a Water Treatment and Hygiene Intervention on Household Drinking Water Quality and Diarrhoea: A Sub-study of the TISA Trial in Senegal

Effect of a Water Treatment and Hygiene Intervention on Household Drinking Water Quality and Diarrhoea: A Sub-study of the TISA Trial in Senegal | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Effect of a Water Treatment and Hygiene Intervention on Household Drinking Water Quality and Diarrhoea: A Sub-study of the TISA Trial in Senegal Laura Braun, Djiby N’Diaye, Matar Ba, Joseph Wells, Francoise Siroma, and 12 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7506201/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Severe acute malnutrition (SAM) affects an estimated 17 million children globally and is increasingly treated at home under the Community-based Management of Acute Malnutrition (CMAM) approach. However, household environmental hazards, particularly unsafe drinking water, may undermine recovery. In the Traitement Intégré de la Sous-Nutrition Aiguë (TISA) cluster-randomised controlled trial in northern Senegal, children aged 6–59 months with uncomplicated SAM were enrolled in outpatient therapeutic programmes. The control group received the standard eight-week national protocol, while the intervention group also received chlorination tablets, a 20-litre storage container, soap, and hygiene promotion. This nested sub-study assessed the impact of the intervention on household water quality and diarrhoea. Among 445 households, drinking water samples collected 4–6 weeks after enrolment showed higher median free chlorine in the intervention group (0.5 mg/L, IQR 0.1–2.0) than controls (0.1 mg/L, IQR 0.1–0.1). Escherichia coli contamination was reduced, with 46% of intervention samples classified as safe (<1 CFU/100 mL) versus 34% in the control. Diarrhoea prevalence declined over time in both groups, with a significantly greater reduction in the intervention arm (global Wald test p=0.028). The intervention substantially improved microbial drinking-water quality and was associated with lower diarrhoea prevalence among children receiving SAM treatment, though residual water contamination remained at levels posing moderate health risk. These findings highlight the potential for integrating targeted water treatment and hygiene measures into CMAM to reduce waterborne disease risk and diarrhoea among children with SAM. Health sciences/Diseases/Nutrition disorders/Malnutrition Health sciences/Health care/Health services Health sciences/Diseases/Gastrointestinal diseases/Intestinal diseases/Diarrhoea Scientific community and society/Water resources Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Severe acute malnutrition (SAM) affected an estimated 13.7 million children under five globally in 2022 (1), and is the most life-threatening form of malnutrition. Children with SAM face heightened susceptibility to infections and an increased risk of mortality (2, 3). Therapeutic feeding programs, such as the Community-based Management of Acute Malnutrition (CMAM) approach, have significantly improved recovery rates by enabling the management of uncomplicated SAM cases within the community (4). However, treatment has transitioned from controlled hospital settings to household care, where poor water, sanitation and hygiene (WASH) conditions and exposure to environmental contamination are often greater. Contaminated drinking water is a major contributor to diarrheal diseases (5), which can undermine nutritional rehabilitation by reducing nutrient absorption and resulting in significant water loss (6). Improving water quality at the household level through treatment and safe storage has the potential to reduce diarrheal disease burden (7), thereby supporting nutritional recovery in children with SAM. However, there is limited evidence on the effective integration of WASH within outpatient therapeutic programs (OTPs), including the fidelity, uptake, and impact on both water quality and child health outcomes of these interventions. Two trials on integrating water treatment kits with SAM treatment have been conducted in Pakistan and Chad (8, 9). Whilst one trial did not assess microbial quality of water and found no significant reduction in diarrhoea prevalence (8), the other reported a significant reduction in the presence of faecal coliforms and the longitudinal prevalence of diarrhoea in the arm using Aquatabs (Medentech, Wexford, Republic of Ireland) to treat water (9). This study was nested within the Traitement Intégré de la Sous-Nutrition Aiguë (TISA) trial in Senegal (clinical trials NCT04667767 (10)), analysed the microbial quality of household drinking water among participants receiving standard OTP alone or OTP combined with a water treatment and hygiene intervention, hereafter referred to as the “WASH kit”. The pre-specified theory of change (Supplementary Information) describes how we hypothesised the intervention to work; that is that if the WASH kit was deployed, delivered and used as intended, the microbial quality of drinking water would improve limiting waterborne exposure to enteric pathogens, and thereby reduce diarrhoeal disease and improve SAM outcomes. The aim of our study was to assess intervention fidelity and participant response (i.e. intervention uptake) to the water treatment component of the intervention, as well as its impact on water quality and reported diarrhoea among children being treated for SAM and their caregivers. Methods Study setting The TISA trial was conducted in the departments of Podor and Linguère in northern Senegal, including four districts – Podor, Pété, Linguère, and Dahra – with a total population of approximately 600,000 people (11). This region is characterised by poor access to basic services (health, education, WASH) and a weak local economy. Livelihoods are largely based on agriculture or nomadic pastoral practice, with traditional labor-intensive practices still prevalent (12). In 2023, the two-week period prevalence of childhood diarrhoea in Senegal was 22%, though significantly higher among children aged 6–23 months (34–36%) (12), coinciding with the weaning period when children transition to solid foods and become more exposed to their environment, increasing pathogen contact. The national prevalence of SAM is also highest in children aged 6–23 months, ranging from 1.3% - 2.4% (12). These overlapping vulnerabilities underscore the urgent need for integrated interventions targeting both nutrition and environmental health. Study design This is a sub-study of the TISA trial, a cluster-randomised controlled trial (cRCT) whereby clusters, corresponding to treatment centres, were randomly allocated to either a control group receiving the standard OTP or an intervention group receiving OTP plus a WASH kit. Participants, children aged 6-59 months being treated for uncomplicated SAM, in both the control and intervention groups received the standard national protocol for OTP for SAM as recommended by the Ministry of Health for Senegal which covers medical treatment, nutrition treatment and infant and young child feeding (13). In addition to the standard OTP protocol, participants in the intervention group received a WASH kit at the first treatment visit from the head nurse of the health centre. The WASH kit consisted of a 20L plastic container, an 8-week supply of Aquatab effervescent chlorine tablets to treat 20L/day, two bars of soap. The WASH kit intervention was delivered by nurses at the treatment centre who provided instruction and demonstration on how to treat water and explained the importance of hand hygiene and when to wash hands with soap. In addition, the WASH kit was promoted through two household visits at four- and eight-weeks admission by a health extension worker. The Aquatabs were distributed together with medication and Ready-to-Use Therapeutic Food (RUTF) at weekly health centre visits to encourage sustained use. Control participants received the WASH kit at the end of enrolment. All participants were followed up for an eight-week period with health outcomes recorded at weekly treatment visits, as per OTP protocol. Additionally, clinical and environmental samples, including water samples were collected. A random subset of 20% of trial participants was invited to take part in this water quality sub-study that assessed the microbial quality of household drinking water. Water samples were collected by enumerators from approximately every fifth household visited during the fourth week of enrolment (plus or minus one week), ensuring a representative subset of the study population. Water sampling was carried out approximately once per week, and any households visited on that day were invited to take part in the sub-study by providing a water sample. The selection of the sub-sample was therefore not randomised by arm. Diarrhoea Diarrhoea was defined as three or more loose stools per day, as per the World Health Organization (WHO) (14) and we assessed the one week period prevalence by asking whether the child had had diarrhoea in the preceding seven days. Baseline diarrhoea was recorded by the head nurse at the health centre immediately following enrolment in the trial. Diarrhoea was then assessed again at week 4 and week 8 by enumerators during unannounced household visits. Sample collection and physiochemical analysis Water samples were collected between 8 February 2021 and 18 August 2022. Unannounced household visits were conducted by trained enumerators four weeks after participants’ enrolment in the trial (supplementary information). A structured household questionnaire (supplementary information) was administered to the child’s primary caregiver and recorded using Open Data Kit (ODK) (15). Household water samples were collected by enumerators, who were not blinded to the intervention allocation. The caregiver was asked to provide approximately one cup of household drinking water from the point of consumption in the vessel used to hydrate the index SAM child. Free chlorine residual and turbidity were tested at the household by the enumerator using a commercial Colour Wheel chlorine test kit (Hach) (detection limit of 0.1 mg/L) and a turbidity tube, respectively. For the microbial assessment, water samples were collected aseptically in 120mL Whirl-Pak Thio-Bags and transported on ice for analysis within six hours at a laboratory. Microbial analysis Water samples were assessed for contamination with indicator bacteria ( Escherichia coli [ E. coli ]and total coliforms), consistent with the WHO Guidelines for drinking water quality (16). For each sample, two volumes between 1-100ml were filtered through 0.45 mm filters (volumes dependent on chlorine residual and expected contamination levels), including one duplicate and blank per day of analysis. Initially, bottled water was used for blanks, which was then replaced by distilled water due to repeated contamination. Filters were placed on prepared petri dishes with pads soaked in m-ColiBlue24 medium and incubated in a portable incubator at 37°C for 24 hours. Red (coliforms) and blue ( E. coli ) colonies were counted and recorded by laboratory personnel, with the sum of all colonies corresponding to total coliforms. Microbial counts are reported as colony-forming units (CFU) per 100 mL for E. coli and total coliforms. All laboratory analysis was conducted by trained lab technicians blinded to the intervention allocation. Quality checks and statistical analysis Questionnaire data were extracted from ODK and cleaned in R statistical software (17). Microbial water results were recorded on paper and copied to excel along with photographs of the data sheet and incubated petri dishes. Data entry was cross-checked with photographs for 10% of the results, which showed less than 2% error between colony counting. There were no double entry errors. Any samples analysed on a day with contaminated or missing blanks were removed. All analyses were conducted using R (17). Descriptive analysis was used to characterise household demographics, WASH conditions, behavioural factors, and water quality indicators. To assess the effect of the intervention on physicochemical and microbial water quality at 4 weeks, a Wilcoxon rank-sum test was used to compare turbidity, E. coli counts, total coliforms counts and residual chlorine, while a Pearson’s Chi-squared test was used to compare the proportion of samples with ³ 0.2 mg/L residual chlorine. To assess the effect of the intervention on E. coli contamination, a zero-inflated negative binomial regression model was fitted to the overdispersed counts of E. coli colony forming units, using robust standard errors to account for clustering. The model was adjusted for age, sex, and variables indicating imbalance at baseline, namely open defecation and diarrhoea prevalence at admission. Logistic regression with cluster-robust standard errors was used to estimate the effect of the intervention over time on weekly diarrhoea prevalence. Models included time and intervention-by-time interaction, and were adjusted for age, sex, open defecation and diarrhoea prevalence at admission. Additional exploratory analyses included the assessment of the association between 1) chlorine residual concentration and the odds of E. coli contamination, 2) microbiologically safe water and the odds of caregiver reported diarrhoea at week 8, and 3) chlorine residual concentration and diarrhoea at week 8 (supplementary information). Ethical approval This study received ethical approval from the National Committee for Bio-Ethics for Senegal (Ref SEN 19/45) and the LSHTM Research Ethics Committee (ref 17511) prior to enrolment of any study participants, and the trial was pre-registered on the clinicaltrials.gov trials registry (NCT04667767). Written informed consent to participate in the study was obtained from caregivers prior to any study procedures. Results Of the 2411 participants enrolled in the TISA trial, a random sample of 520 individuals was invited to participate in this sub-study (Figure 1). All 520 participants provided a drinking water sample at the household visit four weeks after enrolment. Of these, 75 participants were excluded from the analysis, either due to contaminated blanks or an incubator battery failure, meaning a total of 445 samples are included in this analysis (200 control, 245 intervention) (Figure 1, Table 1), distributed across 32 interventional and 35 control clusters. The location of households included in this sub-study are shown in Figure 2. Participant characteristics exhibited some key differences between arms. The mean age was 18 months in both groups, and the proportion of male participants was slightly higher in the control group (62%) than in the intervention group (57%). The distribution of the household wealth index indicates that a higher proportion of participants in the intervention group fell into the lower wealth categories (44% in quintiles 1–2) compared to the control group (32%). In terms of household sanitation, similar proportions of flush toilets and pit latrines were observed in both groups (25%–26%), but open defecation was more common in the intervention group (33%) compared to the control (23%) (Table 1). Use of sanitation facilities shared between multiple households was high in both groups (both 95%). Management of child faeces differed, with more children in the control group using potties (60%) compared to the intervention (44%), while child open defecation was higher in the intervention group (39% vs. 20%). For child faeces disposal, the intervention group showed lower safe disposal (43% vs. 52%) and higher rates of unsafe or no disposal practices (57% vs. 48%). Both groups relied primarily on improved water sources (93%–97%), with household taps being more common in the control group (61%) compared to community taps in the intervention (45%). Animal ownership was higher in the intervention group (82%) than the control (71%). Overall, the intervention group exhibited poorer environmental conditions compared to the control group. Table 1: Household characteristics reported at the household visit, 4 weeks after enrolment. All WASH infrastructure variables were observed by enumerators. SD=standard deviation. *Child faeces disposal in a sanitation facility or buried is considered “safe”, whereas disposal in an open drain, trash or no disposal is considered “unsafe”. Characteristic Control Intervention N = 200 N = 245 Participant age (months, mean ± SD) 18.2 ± 11.3 18.0 ± 11.9 Participant sex: male 124 (62%) 139 (57%) Wealth index 1 (lowest) 37 (19%) 37 (15%) 2 26 (13%) 62 (25%) 3 29 (15%) 48 (20%) 4 41 (21%) 42 (17%) 5 (highest) 57 (29%) 46 (19%) Missing 10 (5%) 10 (4%) Household size 10.9 ± 8 10.0 ± 6.2 Missing 156 212 Household sanitation facility Flush toilet to sewer or tank 50 (25%) 62 (25%) Pit latrine 52 (26%) 61 (25%) Hole and buried 52 (26%) 42 (17%) Open defecation 46 (23%) 80 (33%) Shared sanitation facility 147 (95%) 156 (95%) Missing 46 81 Child faeces management Diaper 39 (20%) 42 (17%) Potty 119 (60%) 107 (44%) Open defecation 40 (20%) 95 (39%) Missing 2 1 Child faeces disposal* Safe 100 (52%) 105 (43%) Unsafe 93 (48%) 138 (57%) Missing 7 2 Water source Improved 184 (93%) 236 (97%) Household tap 121 (61%) 122 (50%) Tap off premises 57 (29%) 109 (45%) Protected well 3 (1.5%) 4 (1.6%) Borehole 3 (1.5%) 1 (0.4%) Unimproved 14 (7%) 7 (3%) Unprotected well 11 (5.5%) 4 (2%) Surface Water 2 (1%) 3 (1%) Bottled Water 1 (0.5%) 0 (0%) Missing 2 2 More than one water source 13 (6.6%) 26 (11%) Animal ownership 138 (71%) 192 (82%) The WASH kit was delivered successfully to the intervention arm, with 95% having the WASH kit at the 4-week household visit versus 1% (3 households) in the control (Table 2). In the intervention arm, 73% reported treating their water, 66% with chlorine tablets distributed by the trial team. This compares to 7% reported water treatment in the control arm. Chlorine tablets were present in 69% of intervention households versus only 1% in the control. The water serving method reflects the type of storage container, with 92% of intervention households and 2% of control households using a faucet, and 7% of the intervention and 63% of the control group dipping the receptacle into the water container directly. Self-reported handwashing was near-universal in both arms, and 98% of intervention households had water and soap present, versus 87% in the control. Table 2: WASH practices at the week 4 household visit Characteristic Control Intervention N = 200 N = 245 Type of water storage container Intervention container (plastic container with lid and tap) 3 (1%) 232 (95%) Clay pot 73 (37%) 11 (5%) Jerrycan 66 (33%) 0 (0%) Plastic bucket 29 (15%) 0 (0%) Buried clay tank 23 (12%) 0 (0%) Plastic bottle or barrel 6 (3%) 0 (0%) Missing 0 2 Covered water container 194 (97%) 242 (100%) Missing 1 2 Household reports treating water 14 (7%) 179 (73%) Missing 0 1 Reported water treatment Chlorine tablets 2 (1%) 166 (68%) Intervention Aquatabs 2 (1%) 162 (66%) Liquid chlorine 10 (5%) 32 (13%) Water settling 3 (1%) 82 (33%) Boiling 0 (0%) 3 (1%) Observed presence of chlorine tablets at household 2 (1%) 168 (69%) Number of chlorine tablets observed at household (median, IQR) 2 (1, 3) 7 (4, 10) Reported time since treating water 1h 0 (0%) 13 (7%) 12h 14 (100%) 130 (73%) 24h 0 (0%) 26 (15%) 48h 0 (0%) 10 (6%) Observed water serving method Using a tap 4 (2%) 225 (92%) Dipping with cup 126 (63%) 17 (7%) Pouring from container 69 (35%) 0 (0%) Missing 1 3 Caregiver-reported handwashing in past 24 hours 193 (97%) 241 (99%) Missing 2 2 Caregiver-reported handwashing with water and soap 174 (87%) 240 (98%) Turbidity was very low (median <5 NTU) in both arms (table 3), and well within the WHO recommendations of <10 NTU for chlorination to be effective (18). Turbidities exceeding 10 NTU may require higher disinfection doses or contact times (18, 19). The median residual chlorine was 0.5 mg/L in the intervention and <0.1 mg/L in the control group, indicating that chlorination was used to treat water in the intervention group. The chlorine residual in the control arm is 0.1 mg/L or less, as the chlorine tester starts with a reading of 0.1 mg/L, making it difficult to distinguish between no- and low-chlorine concentrations (see discussion). A total of 64% intervention and 21% control samples had a chlorine residual of 0.2 mg/L or higher, the minimum level recommended for effective chlorination by WHO. Total coliforms in drinking water samples were significantly lower in the intervention compared to the control group (median 830 CFU/100 mL to 278 CFU/100 mL). This difference is as pronounced for E. coli ; median 5 CFU/100 mL in the control and 1 CFU/100 mL in the intervention group. The mean and standard deviation are included in the supplementary information, and are an order of magnitude higher than the median (e.g., for mean E.coli in intervention is 93 E. coli CFU/100 mL, and 250 CFU/100 mL in the control), given a small proportion of samples with contamination exceeding 1,000 CFU/100 mL for both total coliforms and E.coli (figure 3). The regression analysis indicates that the intervention reduced the rate of E. coli contamination in the intervention arm by 64% (aOR 0.36, CI 0.19, 0.70) compared to the control (table 4). Table 3: Physicochemical and microbial water quality in household drinking water samples collected at the week 4 household visit. Residual chlorine and turbidity were assessed at the household using a pool tester and turbidity tube, respectively. E. coli and total coliforms were assessed at a field laboratory, within six hours of sample collection. P-values for continuous variables were assessed with Wilcoxon rank-sum tests; binary variables were compared using Pearson’s Chi-squared test. Water quality outcome Control Intervention p-value Number of samples 200 245 Turbidity (NTU) – median and IQR <5 IQR (5 - 5) <5 IQR (5 - 5) 0.064 Residual chlorine (mg/L) - median and IQR 0.1 IQR (0.1 - 0.1) 0.5 IQR (0.1 - 2.0) <0.001 % of samples with ³ 0.2 mg/L residual chlorine 21% (42) 64% (157) <0.001 E. coli (CFU/100 mL) – median and IQR 5 (0, 68) 1 (0, 20) 0.003 Total coliforms (CFU/100 mL) – median and IQR 830 (159, 2082) 278 (159, 2082) <0.001 Table 4: Effect of the intervention on microbial water quality and caregiver-reported child diarrhoea Control Intervention Crude effect 1 Adjusted effect 2 Median IQR Median IQR Incidence rate ratio 95% CI p-value Incidence rate ratio 95% CI p-value E. coli (CFU/100 mL) 5 0, 68 1 0, 20 0.36 0.19, 0.70 0.0003 0.36 0.19, 0.70 0.003 Diarrhoea prevalence Control Intervention Crude effect 1 Adjusted effect 2 n/N % n/N % Odds ratio 95% CI p-value 3 Odds ratio 95% CI p-value 3 Week 0 61/200 30.5% 101/245 41.2% 1.00 0.33 1.00 0.028 Week 4 52/198 26.3% 62/244 25.4% 0.96 0.46, 2.00 0.68 0.26, 1.82 Week 8 32/160 20.0% 28/198 14.1% 0.66 0.33, 1.32 0.52 0.24, 1.15 1 Crude effect based on logistic regression with robust standard errors to account for clustering 2 Adjusted for clustering, age, sex, open defecation, and diarrhoea prevalence at admission 3 Global Wald-test p-value for difference in change over time between groups Using WHO standards for drinking water, 46% of water samples in the intervention arm were safe (100 CFU/100 mL) or very high (>1000 CFU/100 mL) risk based on WHO guidance. Figure 4 shows the 7-day period prevalence of caregiver-reported child diarrhoea at enrolment, four and eight weeks of follow-up in both groups. At enrolment (week 0), diarrhoea prevalence was higher in the intervention (41%) compared to the control (31%). Over time, both groups showed reductions, but the intervention group experienced a consistently greater decline, reaching 14% at week 8 compared to 20% in the control group (Figure 4, Table 4). Diarrhoea prevalence declined over time in both the intervention and control groups, from 41% and 31% respectively at week 0, 25% and 26% respectively at week 4 (aOR relative to week 0 0.68, 95%CI 0.26, 1.82), and 14% and 20% respectively at week 8 (OR relative to week 0 0.52, 95% CI 0.24, 1.15). There was strong evidence of a greater reduction in prevalence of diarrhoea in the intervention group than the control group (global Wald test p-value 0.028) (Table 4, Figure 4). Exploratory analyses examining the relationships between chlorine residual, E. coli contamination, and diarrhoea are consistent with the main intervention findings (supplementary table 2). A chlorine residual above 0.2 mg/L was significantly associated with increased odds of microbiologically safe drinking water. However, neither chlorine residual presence nor water safety showed a statistically significant association with caregiver-reported child diarrhoea at week 8. Discussion Our results indicate that this intervention - which integrated drinking water treatment and hygiene promotion into the outpatient treatment of uncomplicated SAM - was successfully implemented through existing health structures. We found high intervention fidelity with almost all participants receiving the intervention as planned and participants responded to the intervention as intended. WASH kits were provided to households and actively used by caregivers, contributing to large improvements in drinking water quality. At the 4-week household visit, 95% of intervention households in the water quality sub-study had the WASH kit, compared to just 1% in the control, demonstrating successful delivery by the local health team. This was reflected in higher reported water treatment rates (73% vs. 7%) and median chlorine residual concentrations (0.5 mg/L vs. 0.1 mg/L) in the intervention group compared to the control. Consistent with this, chlorine residual was significantly associated with safe water (<1 E. coli CFU/100 ml). Improvements in hygiene behaviours, such as handwashing with soap and safe water serving, were also noted—likely reinforced by community health worker visits, which occurred up to twice per household during the trial. A forthcoming TISA process evaluation will examine the factors driving this high fidelity and response. Use of chlorine tablets by caregivers in the intervention group led to significantly lower microbial contamination in drinking water for children treated for SAM, with 46% of intervention samples classified as safe compared to 34% in control—comparable though higher than the 37% safe water rate reported in a similar SAM trial on point-of-use water treatment in Pakistan (9). We observed a lower prevalence of diarrhoea in the intervention group compared to the control group at both 4- and 8-weeks post-admission to outpatient treatment. While the initial prevalence was higher in the intervention group (42%) compared to the control (31%), the reduction was significantly greater in the intervention group prevalence at week 8 (14% vs. 20%). The pattern of reduction in diarrhoea following a water chlorination intervention is consistent with results from the trial in Pakistan, where longitudinal prevalence reduced from 36% to 20% in the Aquatab intervention vs from 29% to 26% in the control arm (9), as well as with a meta-analysis showing protective effects of point-of-use chlorination (RR 0.66, 95% CI 0.56–0.77) (7). The reduction seen in the control group may reflect improvements from nutritional treatment alone. Antibiotic-associated diarrhoea may have contributed to higher diarrhoea prevalence shortly after admission, though less likely at week 4 or 8. These findings highlight the potential of combining water treatment and hygiene interventions with SAM treatment to reduce diarrhoeal prevalence within just eight weeks. However, further reductions may be constrained by the multiple transmission pathways of diarrhoeal disease — including food-borne and environmental contamination —often exacerbated by inadequate sanitation, which the trial did not address. Despite the increased presence of chlorine residuals and improved microbial quality of drinking water, the level of contamination still carried a medium risk, according to WHO guidelines. Additional analyses confirmed that the presence of chlorine residual was significantly associated with safer water, defined as having <1 E. coli CFU/100 mL, supporting the effectiveness of chlorine in reducing microbial contamination. However, this protection was not absolute and may be attributed to factors including incorrect water treatment practices (e.g., dosage, contact time), high levels of source water contamination, or high turbidity. Water should be treated every 24 hours to maintain effective chlorine residual levels that protect against recontamination. Nonetheless, only 15% of households reported having treated water within 24 hours, and 6% up to 48 hours ago, with chlorine residual tending to decrease with time since treatment (supplementary information). Unhygienic water serving, observed in 7% of intervention households, may have led to re-contamination. These findings highlight the need for further investigation into barriers to safe water storage and treatment practices. Although not directly measured, high levels of source water contamination—suggested by the 5% of samples exceeding 1,000 E. coli /100 mL—may have overwhelmed the disinfection capacity of chlorine tablets. The significant reductions in E. coli and total coliform counts, coupled with lower diarrhoea prevalence in the intervention group, provide good evidence that the intervention was successfully implemented and adopted by households. This supports the theory of change, which assumed that the WASH kit significantly improves drinking water quality (supplementary information). The intervention, embedded within the standard 8-week medical treatment for SAM, specifically targeted water quality and hygiene behaviours. However, the data highlight the need for significant investments, especially in addressing open defecation and environmental contamination, to improve water and sanitation infrastructure and services, and thereby mitigate environmental health risks in the long term. The study has several limitations that may affect interpretation. First, the use of pool testers relies on individual interpretation, which introduces variability and potential bias. Their lower detection limit of 0.1 mg/L makes it difficult to distinguish between very low and absent chlorine residuals, potentially leading to an overestimation of chlorine presence in some samples. Similarly, the field-ready turbidity tube has a detection limit of 5 NTU, limiting sensitivity. Caregiver-reported diarrhoea prevalence may introduce reporting bias, though enteric detection in stool samples will provide a more objective measure. Finally, despite random sampling, the control group had fewer samples than the intervention group, though the sample size was met. Sampling was conducted once per week, alternating between zones, in a geographically difficult-to-access area, which limited the total number of samples collected (20). Nonetheless, statistically significant differences were detected between arms for both water quality indicators and diarrhoea prevalence, suggesting the intervention’s impact was sufficiently large to be detected despite the smaller sample size for these outcomes. Conclusion This intervention, which combined a simple WASH kit and hygiene promotion, was implemented with high fidelity and response, resulting in substantial reductions in microbial contamination of household drinking water. Its integration into the standard OTP led to a significant reduction in diarrhoea prevalence, addressing a key determinant of malnutrition. As diarrhoea both contributes to and exacerbates malnutrition, this integration may help disrupt the cycle between infection and malnutrition, ultimately improving child health outcomes. However, the residual water contamination underscores the need for broader improvements in community-level WASH infrastructure to ensure safe water access beyond the duration of SAM treatment. Policymakers should therefore consider embedding WASH interventions within nutrition programmes to enhance their impact, while also investing in sustainable, long-term solutions to address environmental health risks. References United Nations Children’s Fund (UNICEF), World Health Organization (WHO), International Bank for Reconstruction and Development, The World Bank. Levels and trends in child malnutrition: UNICEF / WHO / World Bank Group Joint Child Malnutrition Estimates: Key findings of the 2023 edition 2023 [Available from: https://data.unicef.org/resources/jme-report-2023/. Black RE, Allen LH, Bhutta ZA, Caulfield LE, de Onis M, Ezzati M, et al. Maternal and child undernutrition: global and regional exposures and health consequences. The Lancet. 2008;371(9608):243-60. Irena AH, Mwambazi M, Mulenga V. Diarrhea is a Major killer of Children with Severe Acute Malnutrition Admitted to Inpatient Set-up in Lusaka, Zambia. Nutrition Journal. 2011;10(1):110. Collins S, Dent N, Binns P, Bahwere P, Sadler K, Hallam A. Management of severe acute malnutrition in children. Lancet. 2006;368(9551):1992-2000. Kyu HH, Vongpradith A, Dominguez R-MV, Ma J, Albertson SB, Novotney A, et al. 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Doocy S, Tappis H, Villeminot N, Suk A, Kumar D, Fazal S, et al. Point-of-use water treatment improves recovery rates among children with severe acute malnutrition in Pakistan: results from a site-randomized trial. Public Health Nutr. 2018;21(16):3080-90. ClinicalTrials.gov. The TISA Trial - Senegal (TISA) 2020 [Available from: https://clinicaltrials.gov/study/NCT04667767. Agence Nationale de la Statistique et de la Démographie Sénégal. Recensement Général de La Population et de l’Habitat, de l’Agriculture et de l’Elevage (RGPHAE): Rapport Définitif.; 2013. Agence Nationale de la Statistique et de la Démographie Sénégal, ICF. Sénégal: Enquête Démographique et de Santé Continue (EDS-Continue) 2023. 2024 [Available from: https://www.ansd.sn/sites/default/files/2024-07/Rapport-tableaux-EDS-C_2023.pdf. Ministère de la Santé. Protocole de prise en charge de la malnutrition aigüe.; 2010. World Health Organization. Diarrhoeal disease. Key facts 2017. Available from: https://www.who.int/news-room/fact-sheets/detail/diarrhoeal-disease. Open Data Kit Team. Open Data Kit. 2021. World Health Organization. Guidelines for drinking-water quality: fourth edition incorporating the first and second addenda. 2022 [Available from: https://iris.who.int/bitstream/handle/10665/352532/9789240045064-eng.pdf?sequence=1. RStudio Team. RStudio. USA: Posit; 2020. World Health Organization. Water Quality and Health - Review of Turbidity: Information for regulators and water suppliers. Technical Brief WHO/FWC/WSH/17.01 2017 [Available from: https://iris.who.int/bitstream/handle/10665/254631/WHO-FWC-WSH-17.01-eng.pdf?sequence=1. LeChevallier MW, Evans TM, Seidler RJ. Effect of turbidity on chlorination efficiency and bacterial persistence in drinking water. Appl Environ Microbiol. 1981;42(1):159-67. N'Diaye DS, Frison S, Ba M, Lê ML, Cabo AE, Siroma F, et al. Implementing a pragmatic randomised controlled trial in a humanitarian setting: lessons learned from the TISA trial. Trials. 2024;25(1):620. Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.docx Supplementary Information Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7506201","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":508537051,"identity":"754f3ebb-e075-42bd-ab43-bad5a2acfba1","order_by":0,"name":"Laura 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Medicine","correspondingAuthor":false,"prefix":"","firstName":"Oliver","middleName":"","lastName":"Cumming","suffix":""}],"badges":[],"createdAt":"2025-09-01 08:40:37","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7506201/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7506201/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":93571891,"identity":"38093854-52fd-40e5-9e86-7afc73f7b526","added_by":"auto","created_at":"2025-10-15 09:06:15","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":32145,"visible":true,"origin":"","legend":"\u003cp\u003eParticipant flow diagram\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7506201/v1/c7cf6942c5aec4292574d8c5.png"},{"id":93571895,"identity":"7a8531fe-83b8-4a8a-9e82-b6c38b23a761","added_by":"auto","created_at":"2025-10-15 09:06:16","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":235550,"visible":true,"origin":"","legend":"\u003cp\u003eMap showing households included in this water quality sub-study of the TISA trial\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7506201/v1/a1f288becdf1ad983d3f3328.png"},{"id":93571892,"identity":"0fdfcec0-6ce8-408d-b512-0fba747b15e2","added_by":"auto","created_at":"2025-10-15 09:06:16","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":31102,"visible":true,"origin":"","legend":"\u003cp\u003eE. coli contamination in drinking water samples according to WHO classifications (not detected/low/medium/ high/very high risk)\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7506201/v1/e91764cfefc892cfeb671ca8.png"},{"id":93574027,"identity":"823bfb07-d1e8-47e2-a7a3-825b1ba24fa7","added_by":"auto","created_at":"2025-10-15 09:14:16","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":47318,"visible":true,"origin":"","legend":"\u003cp\u003eCaregiver-reported child diarrhoea prevalence (7-day recall). Baseline data was collected at the health centre by a nurse. Week 4 and week 8 data were collected at the household by trial enumerators. The global Wald test p-value for difference in change over time between groups is 0.028 (see table 4).\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7506201/v1/3107492f96ca9353791c5dff.png"},{"id":93575102,"identity":"7f427099-8136-4c92-b855-f7f503d642e4","added_by":"auto","created_at":"2025-10-15 09:22:16","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1074449,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7506201/v1/6884a484-5fca-479c-900c-34a4d4e12763.pdf"},{"id":93571894,"identity":"49a6dc98-cddd-4219-a55c-bd8044b70faf","added_by":"auto","created_at":"2025-10-15 09:06:16","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":1361375,"visible":true,"origin":"","legend":"Supplementary Information","description":"","filename":"SupplementaryInformation.docx","url":"https://assets-eu.researchsquare.com/files/rs-7506201/v1/d3267009ece804abd5a042dd.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Effect of a Water Treatment and Hygiene Intervention on Household Drinking Water Quality and Diarrhoea: A Sub-study of the TISA Trial in Senegal","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSevere acute malnutrition (SAM) affected an estimated 13.7 million children under five globally in 2022 (1), and is the most life-threatening form of malnutrition. Children with SAM face heightened susceptibility to infections and an increased risk of mortality (2, 3). Therapeutic feeding programs, such as the Community-based Management of Acute Malnutrition (CMAM) approach, have significantly improved recovery rates by enabling the management of uncomplicated SAM cases within the community (4). However, treatment has transitioned from controlled hospital settings to household care, where poor water, sanitation and hygiene (WASH) conditions and exposure to environmental contamination are often greater.\u0026nbsp;Contaminated drinking water is a major contributor to diarrheal diseases (5), which can undermine nutritional rehabilitation by reducing nutrient absorption and resulting in significant water loss (6).\u003c/p\u003e\n\u003cp\u003eImproving water quality at the household level through treatment and safe storage has the potential to reduce diarrheal disease burden (7), thereby supporting nutritional recovery in children with SAM. However, there is limited evidence on the effective integration of WASH within outpatient therapeutic programs (OTPs), including the fidelity, uptake, and impact on both water quality and child health outcomes of these interventions. Two trials on integrating water treatment kits with SAM treatment have been conducted in Pakistan and Chad (8, 9). Whilst one trial did not assess microbial quality of water and found no significant reduction in diarrhoea prevalence (8), the other reported a significant reduction in the presence of faecal coliforms and the longitudinal prevalence of diarrhoea in the arm using Aquatabs (Medentech, Wexford, Republic of Ireland) to treat water (9).\u003c/p\u003e\n\u003cp\u003eThis study was \u0026nbsp;nested within the Traitement Intégré de la Sous-Nutrition Aiguë (TISA) trial in Senegal (clinical trials\u0026nbsp;NCT04667767 (10)), analysed the microbial quality of household drinking water among participants receiving standard OTP alone or OTP combined with a water treatment and hygiene intervention, hereafter referred to as the “WASH kit”. The pre-specified theory of change (Supplementary Information) describes how we hypothesised the intervention to work; that is that if the WASH kit was deployed, delivered and used as intended, the microbial quality of drinking water would improve limiting waterborne exposure to enteric pathogens, and thereby reduce diarrhoeal disease and improve SAM outcomes. The aim of our study was to assess intervention fidelity and participant response (i.e. intervention uptake) to the water treatment component of the intervention, as well as its impact on water quality and reported diarrhoea among children being treated for SAM and their caregivers.\u0026nbsp;\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003eStudy setting\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe TISA trial was conducted in the departments of Podor and Linguère in northern Senegal, including four districts – Podor, Pété, Linguère, and Dahra – with a total population of approximately 600,000 people (11). This region is characterised by poor access to basic services (health, education, WASH) and a weak local economy. Livelihoods are largely based on agriculture or nomadic pastoral practice, with traditional labor-intensive practices still prevalent (12).\u003c/p\u003e\n\u003cp\u003eIn 2023, the two-week period prevalence of childhood diarrhoea in Senegal was 22%, though significantly higher among children aged 6–23 months (34–36%) (12), coinciding with the weaning period when children transition to solid foods and become more exposed to their environment, increasing pathogen contact. The national prevalence of SAM is also highest in children aged 6–23 months, ranging from 1.3% - 2.4% (12). These overlapping vulnerabilities underscore the urgent need for integrated interventions targeting both nutrition and environmental health.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStudy design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis is a sub-study of the TISA trial, a cluster-randomised controlled trial (cRCT) whereby clusters, corresponding to treatment centres, were randomly allocated to either a control group receiving the standard OTP or an intervention group receiving OTP plus a WASH kit.\u0026nbsp;Participants, children aged 6-59 months being treated for uncomplicated SAM, in both the control and intervention groups received the standard national protocol for OTP for SAM as recommended by the Ministry of Health for Senegal which covers medical treatment, nutrition treatment and infant and young child feeding (13). In addition to the standard OTP protocol, participants in the intervention group received a WASH kit at the first treatment visit from the head nurse of the health centre.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe WASH kit consisted of\u0026nbsp;a 20L plastic container, an 8-week supply of Aquatab effervescent chlorine tablets to treat 20L/day, two bars of soap. The WASH kit intervention was delivered by nurses at the treatment centre who provided instruction and demonstration on how to treat water and explained the importance of hand hygiene and when to wash hands with soap. In addition, the WASH kit was promoted through two household visits at four- and eight-weeks admission by a health extension worker. The Aquatabs were distributed together with medication and Ready-to-Use Therapeutic Food (RUTF) at weekly health centre visits to encourage sustained use. Control participants received the WASH kit at the end of enrolment.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll participants were followed up for an eight-week period with health outcomes recorded at weekly treatment visits, as per OTP protocol. Additionally, clinical and environmental samples, including water samples were collected. A random subset of 20% of trial participants was invited to take part in this water quality sub-study that assessed the microbial quality of household drinking water. Water samples were collected by enumerators from approximately every fifth household visited during the fourth week of enrolment (plus or minus one week), ensuring a representative subset of the study population. Water sampling was carried out approximately once per week, and any households visited on that day were invited to take part in the sub-study by providing a water sample. The selection of the sub-sample was therefore not randomised by arm.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiarrhoea\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDiarrhoea was defined as three or more loose stools per day, as per the World Health Organization (WHO) (14) and we assessed the one week period prevalence by asking whether the child had had diarrhoea in the preceding seven days. Baseline diarrhoea was recorded by the head nurse at the health centre immediately following enrolment in the trial. Diarrhoea was then assessed again at week 4 and week 8 by enumerators during unannounced household visits.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSample collection and physiochemical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWater samples were collected between 8 February 2021 and 18 August 2022. Unannounced household visits were conducted by trained enumerators four weeks after participants’ enrolment in the trial (supplementary information). A structured household questionnaire (supplementary information) was administered to the child’s primary caregiver and recorded using Open Data Kit (ODK) (15).\u0026nbsp;Household water samples were collected by enumerators, who were not blinded to the intervention allocation. The caregiver was asked to provide approximately one cup of household drinking water from the point of consumption in the vessel used to hydrate the index SAM child. Free chlorine residual and turbidity were tested at the household by the enumerator using a commercial Colour Wheel chlorine test kit (Hach) (detection limit of 0.1 mg/L) and a turbidity tube, respectively. For the microbial assessment, water samples were collected aseptically in 120mL Whirl-Pak Thio-Bags and transported on ice for analysis within six hours at a laboratory.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMicrobial analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWater samples were assessed for contamination with indicator bacteria (\u003cem\u003eEscherichia coli\u0026nbsp;\u003c/em\u003e[\u003cem\u003eE. coli\u003c/em\u003e]and total coliforms), consistent with the WHO \u003cem\u003eGuidelines for drinking water quality\u0026nbsp;\u003c/em\u003e(16).\u0026nbsp;For each sample, two volumes between 1-100ml were filtered through 0.45 mm filters (volumes dependent on chlorine residual and expected contamination levels), including one duplicate and blank per day of analysis. Initially, bottled water was used for blanks, which was then replaced by distilled water due to repeated contamination. Filters were placed on prepared petri dishes with pads soaked in m-ColiBlue24 medium and incubated in a portable incubator at 37°C for 24 hours. Red (coliforms) and blue (\u003cem\u003eE. coli\u003c/em\u003e) colonies were counted and recorded by laboratory personnel, with the sum of all colonies corresponding to total coliforms. Microbial counts are reported as colony-forming units (CFU) per 100 mL for \u003cem\u003eE. coli\u0026nbsp;\u003c/em\u003eand total coliforms. All laboratory analysis was conducted by trained lab technicians blinded to the intervention allocation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eQuality checks and statistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eQuestionnaire data were extracted from ODK and cleaned in R statistical software (17). Microbial water results were recorded on paper and copied to excel along with photographs of the data sheet and incubated petri dishes. Data entry was cross-checked with photographs for 10% of the results, which showed less than 2% error between colony counting. There were no double entry errors. Any samples analysed on a day with contaminated or missing blanks were removed. All analyses were conducted using R (17). Descriptive analysis was used to characterise household demographics, WASH conditions, behavioural factors, and water quality indicators. To assess the effect of the intervention on physicochemical and microbial water quality at 4 weeks, a Wilcoxon rank-sum test was used to compare turbidity, \u003cem\u003eE. coli\u003c/em\u003e counts, total coliforms counts and residual chlorine, while a Pearson’s Chi-squared test was used to compare the proportion of samples with\u0026nbsp;³\u0026nbsp;0.2 mg/L residual chlorine.\u003c/p\u003e\n\u003cp\u003eTo assess the effect of the intervention on \u003cem\u003eE. coli\u003c/em\u003e contamination, a zero-inflated negative binomial regression model was fitted to the overdispersed counts of \u003cem\u003eE. coli\u0026nbsp;\u003c/em\u003ecolony forming units, using\u0026nbsp;robust standard errors to account for clustering. The model was adjusted for age, sex, and variables indicating imbalance at baseline, namely open defecation and diarrhoea prevalence at admission. Logistic regression with cluster-robust standard errors was used to estimate the effect of the intervention over time on weekly diarrhoea prevalence. Models included time and intervention-by-time interaction, and were adjusted for age, sex, open defecation and diarrhoea prevalence at admission. Additional exploratory analyses included the assessment of the association between 1) chlorine residual concentration and the odds of \u003cem\u003eE. coli\u003c/em\u003e contamination, 2) microbiologically safe water and the odds of caregiver reported diarrhoea at week 8, and 3) chlorine residual concentration and diarrhoea at week 8 (supplementary information).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study received ethical approval from the National Committee for Bio-Ethics for Senegal (Ref SEN 19/45) and the LSHTM Research Ethics Committee (ref 17511) prior to enrolment of any study participants, and the trial was pre-registered on the clinicaltrials.gov trials registry (NCT04667767). Written informed consent to participate in the study was obtained from caregivers prior to any study procedures.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eOf the 2411 participants enrolled in the TISA trial, a random sample of 520 individuals was invited to participate in this sub-study (Figure 1). All 520 participants provided a drinking water sample at the household visit four weeks after enrolment. Of these, 75 participants were excluded from the analysis, either due to contaminated blanks or an incubator battery failure, meaning a total of 445 samples are included in this analysis (200 control, 245 intervention) (Figure 1, Table 1), distributed across 32 interventional and 35 control clusters. The location of households included in this sub-study are shown in Figure 2.\u003c/p\u003e\n\u003cp\u003eParticipant characteristics exhibited some key differences between arms. The mean age was 18 months in both groups, and the proportion of male participants was slightly higher in the control group (62%) than in the intervention group (57%). The distribution of the household wealth index indicates that a higher proportion of participants in the intervention group fell into the lower wealth categories (44% in quintiles 1\u0026ndash;2) compared to the control group (32%). In terms of household sanitation, similar proportions of flush toilets and pit latrines were observed in both groups (25%\u0026ndash;26%), but open defecation was more common in the intervention group (33%) compared to the control (23%) (Table 1). Use of sanitation facilities shared between multiple households was high in both groups (both 95%). Management of child faeces differed, with more children in the control group using potties (60%) compared to the intervention (44%), while child open defecation was higher in the intervention group (39% vs. 20%). For child faeces disposal, the intervention group showed lower safe disposal (43% vs. 52%) and higher rates of unsafe or no disposal practices (57% vs. 48%). Both groups relied primarily on improved water sources (93%\u0026ndash;97%), with household taps being more common in the control group (61%) compared to community taps in the intervention (45%). Animal ownership was higher in the intervention group (82%) than the control (71%). Overall, the intervention group exhibited poorer environmental conditions compared to the control group.\u003c/p\u003e\n\u003cp\u003eTable 1: Household characteristics reported at the household visit, 4 weeks after enrolment. All WASH infrastructure variables were observed by enumerators. SD=standard deviation. *Child faeces disposal in a sanitation facility or buried is considered \u0026ldquo;safe\u0026rdquo;, whereas disposal in an open drain, trash or no disposal is considered \u0026ldquo;unsafe\u0026rdquo;.\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"482\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristic\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntervention\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eN = 200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eN = 245\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003eParticipant age (months, mean\u0026nbsp;\u0026plusmn;\u0026nbsp;SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e18.2 \u0026plusmn; 11.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e18.0 \u0026plusmn; 11.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003eParticipant sex: male\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e124 (62%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e139 (57%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003eWealth index\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 1 (lowest)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e37 (19%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e37 (15%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e26 (13%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e62 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e29 (15%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e48 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e41 (21%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e42 (17%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 5 (highest)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e57 (29%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e46 (19%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e10 (5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e10 (4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003eHousehold size\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e10.9\u0026nbsp;\u0026plusmn; 8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e10.0\u0026nbsp;\u0026plusmn; 6.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e156\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e212\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 378px;\"\u003e\n \u003cp\u003eHousehold sanitation facility\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Flush toilet to sewer or tank\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e50 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e62 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Pit latrine\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e52 (26%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e61 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Hole and buried\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e52 (26%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e42 (17%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Open defecation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e46 (23%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e80 (33%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003eShared sanitation facility\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e147 (95%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e156 (95%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e81\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 378px;\"\u003e\n \u003cp\u003eChild faeces management\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Diaper\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e39 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e42 (17%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Potty\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e119 (60%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e107 (44%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Open defecation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e40 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e95 (39%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 482px;\"\u003e\n \u003cp\u003eChild faeces disposal*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;Safe\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e100 (52%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e105 (43%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Unsafe\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e93 (48%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e138 (57%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 378px;\"\u003e\n \u003cp\u003eWater source\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Improved\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e184 (93%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e236 (97%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Household tap\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 121 (61%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 122 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Tap off premises\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;57 (29%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;109 (45%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Protected well\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 3 (1.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 4 (1.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Borehole\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;3 (1.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;1 (0.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Unimproved\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e14 (7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e7 (3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Unprotected well\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;11 (5.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;4 (2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Surface Water\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 3 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Bottled Water\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;1 (0.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;2\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003eMore than one water source\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e13 (6.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e26 (11%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003eAnimal ownership\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e138 (71%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e192 (82%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe WASH kit was delivered successfully to the intervention arm, with 95% having the WASH kit at the 4-week household visit versus 1% (3 households) in the control (Table 2). In the intervention arm, 73% reported treating their water, 66% with chlorine tablets distributed by the trial team. This compares to 7% reported water treatment in the control arm. Chlorine tablets were present in 69% of intervention households versus only 1% in the control. The water serving method reflects the type of storage container, with 92% of intervention households and 2% of control households using a faucet, and 7% of the intervention and 63% of the control group dipping the receptacle into the water container directly. Self-reported handwashing was near-universal in both arms, and 98% of intervention households had water and soap present, versus 87% in the control.\u003c/p\u003e\n\u003cp\u003eTable 2: WASH practices at the week 4 household visit\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"587\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristic\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntervention\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003eN = 200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eN = 245\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 454px;\"\u003e\n \u003cp\u003eType of water storage container\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Intervention container (plastic container with lid and tap)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e3 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e232 (95%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Clay pot\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e73 (37%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e11 (5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Jerrycan\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e66 (33%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Plastic bucket\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e29 (15%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Buried clay tank\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e23 (12%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Plastic bottle or barrel\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e6 (3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003eCovered water container\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e194 (97%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e242 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003eHousehold reports treating water\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e14 (7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e179 (73%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 454px;\"\u003e\n \u003cp\u003eReported water treatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Chlorine tablets\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e2 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e166 (68%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Intervention Aquatabs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e2 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e162 (66%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Liquid chlorine\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e10 (5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e32 (13%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Water settling\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e3 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e82 (33%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Boiling\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e3 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003eObserved presence of chlorine tablets at household\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e2 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e168 (69%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003eNumber of chlorine tablets observed at household (median, IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e2 (1, 3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e7 (4, 10)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 454px;\"\u003e\n \u003cp\u003eReported time since treating water\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1h\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e13 (7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 12h\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e14 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e130 (73%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 24h\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e26 (15%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 48h\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e10 (6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003eObserved water serving method\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Using a tap\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e4 (2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e225 (92%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Dipping with cup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e126 (63%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e17 (7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Pouring from container\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e69 (35%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003eCaregiver-reported handwashing in past 24 hours\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e193 (97%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e241 (99%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 330px;\"\u003e\n \u003cp\u003eCaregiver-reported handwashing with water and soap\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e174 (87%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e240 (98%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTurbidity was very low (median \u0026lt;5 NTU) in both arms (table 3), and well within the WHO recommendations of \u0026lt;10 NTU for chlorination to be effective (18). Turbidities exceeding 10 NTU may require higher disinfection doses or contact times (18, 19). The median residual chlorine was 0.5 mg/L in the intervention and \u0026lt;0.1 mg/L in the control group, indicating that chlorination was used to treat water in the intervention group. The chlorine residual in the control arm is 0.1 mg/L or less, as the chlorine tester starts with a reading of 0.1 mg/L, making it difficult to distinguish between no- and low-chlorine concentrations (see discussion). A total of 64% intervention and 21% control samples had a chlorine residual of 0.2 mg/L or higher, the minimum level recommended for effective chlorination by WHO. Total coliforms in drinking water samples were significantly lower in the intervention compared to the control group (median 830 CFU/100 mL to 278 CFU/100 mL). This difference is as pronounced for \u003cem\u003eE. coli\u003c/em\u003e; median 5 CFU/100 mL in the control and 1 CFU/100 mL in the intervention group. The mean and standard deviation are included in the supplementary information, and are an order of magnitude higher than the median (e.g., for mean \u003cem\u003eE.coli\u003c/em\u003e in intervention is 93 \u003cem\u003eE. coli\u003c/em\u003e CFU/100 mL, and 250 CFU/100 mL in the control), given a small proportion of samples with contamination exceeding 1,000 CFU/100 mL for both total coliforms and \u003cem\u003eE.coli\u0026nbsp;\u003c/em\u003e(figure 3). The regression analysis indicates that the intervention reduced the rate of \u003cem\u003eE. coli\u003c/em\u003e contamination in the intervention arm by 64% (aOR 0.36, CI 0.19, 0.70) compared to the control (table 4).\u003c/p\u003e\n\u003cp\u003eTable 3: Physicochemical and microbial water quality in household drinking water samples collected at the week 4 household visit. Residual chlorine and turbidity were assessed at the household using a pool tester and turbidity tube, respectively. E. coli and total coliforms were assessed at a field laboratory, within six hours of sample collection. P-values for continuous variables were assessed with Wilcoxon rank-sum tests; binary variables were compared using Pearson\u0026rsquo;s Chi-squared test.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"595\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWater quality outcome\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntervention\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003eNumber of samples\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e245\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003eTurbidity (NTU) \u0026ndash; median and IQR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026lt;5 IQR (5 - 5)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026lt;5 IQR (5 - 5)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0.064\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003eResidual chlorine (mg/L) - median and IQR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e0.1 IQR (0.1 - 0.1)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e0.5 IQR (0.1 - 2.0)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003e% of samples with \u0026sup3; 0.2 mg/L residual chlorine\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e21% (42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e64% (157)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003e\u003cem\u003eE. coli\u003c/em\u003e (CFU/100 mL) \u0026ndash; median and IQR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e5 (0, 68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e1 (0, 20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003eTotal coliforms (CFU/100 mL) \u0026ndash; median and IQR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e830 (159, 2082)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e278 (159, 2082)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 4: Effect of the intervention on microbial water quality and caregiver-reported child diarrhoea\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"600\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 16.6666%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntervention\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"7\" valign=\"top\" style=\"width: 27.1667%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCrude effect\u003csup\u003e1\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"6\" valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdjusted effect\u003csup\u003e2\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eMedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 38px;\"\u003e\n \u003cp\u003eIQR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003eMedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 7.8333%;\"\u003e\n \u003cp\u003eIQR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 11.1667%;\"\u003e\n \u003cp\u003eIncidence rate ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003eIncidence rate ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eE. coli\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;(CFU/100 mL)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 38px;\"\u003e\n \u003cp\u003e0, 68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 7.8333%;\"\u003e\n \u003cp\u003e0, 20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 11.1667%;\"\u003e\n \u003cp\u003e0.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.19, 0.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.0003\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.19, 0.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"21\" style=\"width: 600px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDiarrhoea prevalence\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 97px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntervention\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCrude effect\u003csup\u003e1\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"7\" valign=\"top\" style=\"width: 166px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdjusted effect\u003csup\u003e2\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 45px;\"\u003e\n \u003cp\u003en/N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003en/N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003eOdds ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003ep-value\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003eOdds ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003ep-value\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 0px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeek 0\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 45px;\"\u003e\n \u003cp\u003e61/200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e30.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e101/245\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e41.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" rowspan=\"3\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" rowspan=\"3\" style=\"width: 50px;\"\u003e\n \u003cp\u003e0.028\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 0px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeek 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 45px;\"\u003e\n \u003cp\u003e52/198\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e26.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e62/244\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e25.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e0.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.46, 2.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.26, 1.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 0px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeek 8\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 45px;\"\u003e\n \u003cp\u003e32/160\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e20.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e28/198\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e14.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e0.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.33, 1.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.24, 1.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 0px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cem\u003e\u003csup\u003e1\u0026nbsp;\u003c/sup\u003e\u003c/em\u003e\u003cem\u003eCrude effect based on logistic regression with robust standard errors to account for clustering\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/em\u003e\u003cem\u003e\u0026nbsp;Adjusted for clustering, age, sex, open defecation, and diarrhoea prevalence at admission\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003csup\u003e3\u0026nbsp;\u003c/sup\u003e\u003c/em\u003e\u003cem\u003eGlobal Wald-test p-value for difference in change over time between groups\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eUsing WHO standards for drinking water, 46% of water samples in the intervention arm were safe (\u0026lt;1 \u003cem\u003eE. coli\u003c/em\u003e CFU/100 ml), compared to only 34% in the control (figure 3). By contrast, 11% of intervention and 21% of control samples are considered high (\u0026gt;100 CFU/100 mL) or very high (\u0026gt;1000 CFU/100 mL) risk based on WHO guidance.\u003c/p\u003e\n\u003cp\u003eFigure 4 shows the 7-day period prevalence of caregiver-reported child diarrhoea at enrolment, four and eight weeks of follow-up in both groups. At enrolment (week 0), diarrhoea prevalence was higher in the intervention (41%) compared to the control (31%). Over time, both groups showed reductions, but the intervention group experienced a consistently greater decline, reaching 14% at week 8 compared to 20% in the control group (Figure 4, Table 4). Diarrhoea prevalence declined over time in both the intervention and control groups, from 41% and 31% respectively at week 0, 25% and 26% respectively at week 4 (aOR relative to week 0 0.68, 95%CI 0.26, 1.82), and 14% and 20% respectively at week 8 (OR relative to week 0 0.52, 95% CI 0.24, 1.15). There was strong evidence of a greater reduction in prevalence of diarrhoea in the intervention group than the control group (global Wald test p-value 0.028) (Table 4, Figure 4).\u003c/p\u003e\n\u003cp\u003eExploratory analyses examining the relationships between chlorine residual, \u003cem\u003eE. coli\u003c/em\u003e contamination, and diarrhoea are consistent with the main intervention findings (supplementary table 2). A chlorine residual above 0.2 mg/L was significantly associated with increased odds of microbiologically safe drinking water. However, neither chlorine residual presence nor water safety showed a statistically significant association with caregiver-reported child diarrhoea at week 8.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur results indicate that this intervention - which integrated drinking water treatment and hygiene promotion into the outpatient treatment of uncomplicated SAM - was successfully implemented through existing health structures. We found high intervention fidelity with almost all participants receiving the intervention as planned and participants responded to the intervention as intended. WASH kits were provided to households and actively used by caregivers, contributing to large improvements in drinking water quality.\u003c/p\u003e\n\u003cp\u003eAt the 4-week household visit, 95% of intervention households in the water quality sub-study had the WASH kit, compared to just 1% in the control, demonstrating successful delivery by the local health team. This was reflected in higher reported water treatment rates (73% vs. 7%) and median chlorine residual concentrations (0.5 mg/L vs. 0.1 mg/L) in the intervention group compared to the control. Consistent with this, chlorine residual was significantly associated with safe water (\u0026lt;1 \u003cem\u003eE. coli\u003c/em\u003e CFU/100 ml). Improvements in hygiene behaviours, such as handwashing with soap and safe water serving, were also noted—likely reinforced by community health worker visits, which occurred up to twice per household during the trial. A forthcoming TISA process evaluation will examine the factors driving this high fidelity and response. Use of chlorine tablets by caregivers in the intervention group led to significantly lower microbial contamination in drinking water for children treated for SAM, with 46% of intervention samples classified as safe compared to 34% in control—comparable though higher than the 37% safe water rate reported in a similar SAM trial on point-of-use water treatment in Pakistan\u0026nbsp;(9).\u003c/p\u003e\n\u003cp\u003eWe observed a lower prevalence of diarrhoea in the intervention group compared to the control group at both 4- and 8-weeks post-admission to outpatient treatment. While the initial prevalence was higher in the intervention group (42%) compared to the control (31%), the reduction was significantly greater in the intervention group prevalence at week 8 (14% vs. 20%). The pattern of reduction in diarrhoea following a water chlorination intervention is consistent with results from the trial in Pakistan, where longitudinal prevalence reduced from 36% to 20% in the Aquatab intervention vs from 29% to 26% in the control arm\u0026nbsp;(9),\u0026nbsp;as well as with a meta-analysis showing protective effects of point-of-use chlorination (RR 0.66, 95% CI 0.56–0.77)\u0026nbsp;(7). The reduction seen in the control group may reflect improvements from nutritional treatment alone. Antibiotic-associated diarrhoea may have contributed to higher diarrhoea prevalence shortly after admission, though less likely at week 4 or 8. These findings highlight the potential of combining water treatment and hygiene interventions with SAM treatment to reduce diarrhoeal prevalence within just eight weeks. However, further reductions may be constrained by the multiple transmission pathways of diarrhoeal disease — including food-borne and environmental contamination —often exacerbated by inadequate sanitation, which the trial did not address.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDespite the increased presence of chlorine residuals and improved microbial quality of drinking water, the level of contamination still carried a medium risk, according to WHO guidelines.\u0026nbsp;Additional analyses confirmed that the presence of chlorine residual was significantly associated with safer water, defined as having \u0026lt;1 \u003cem\u003eE. coli\u003c/em\u003e CFU/100 mL, supporting the effectiveness of chlorine in reducing microbial contamination. However, this protection was not absolute and may be attributed to factors including incorrect water treatment practices\u0026nbsp;(e.g., dosage, contact time), high levels of source water contamination, or high turbidity.\u0026nbsp;Water should be treated every 24 hours to maintain effective chlorine residual levels that protect against recontamination. Nonetheless, only 15% of households reported having treated water within 24 hours, and 6% up to 48 hours ago, with chlorine residual tending to decrease with time since treatment (supplementary information). Unhygienic water serving, observed in 7% of intervention households, may have led to re-contamination. These findings highlight the need for further investigation into barriers to safe water storage and treatment practices. Although not directly measured, high levels of source water contamination—suggested by the 5% of samples exceeding 1,000 \u003cem\u003eE. coli\u003c/em\u003e/100 mL—may have overwhelmed the disinfection capacity of chlorine tablets.\u003c/p\u003e\n\u003cp\u003eThe significant reductions in \u003cem\u003eE. coli\u003c/em\u003e and total coliform counts, coupled with lower diarrhoea prevalence in the intervention group, provide good evidence that the intervention was successfully implemented and adopted by households. This supports the theory of change, which assumed that the WASH kit significantly improves drinking water quality (supplementary information). The intervention, embedded within the standard 8-week medical treatment for SAM, specifically targeted water quality and hygiene behaviours. However, the data highlight the need for significant investments, especially in addressing open defecation and environmental contamination, to improve water and sanitation infrastructure and services, and thereby mitigate environmental health risks in the long term.\u003c/p\u003e\n\u003cp\u003eThe study has several limitations that may affect interpretation. First, the use of pool testers relies on individual interpretation, which introduces variability and potential bias. Their lower detection limit of 0.1 mg/L makes it difficult to distinguish between very low and absent chlorine residuals, potentially leading to an overestimation of chlorine presence in some samples. Similarly, the field-ready turbidity tube has a detection limit of 5 NTU, limiting sensitivity. Caregiver-reported diarrhoea prevalence may introduce reporting bias, though enteric detection in stool samples will provide a more objective measure. Finally, despite random sampling, the control group had fewer samples than the intervention group, though the sample size was met. Sampling was conducted once per week, alternating between zones, in a geographically difficult-to-access area, which limited the total number of samples collected (20). Nonetheless, statistically significant differences were detected between arms for both water quality indicators and diarrhoea prevalence, suggesting the intervention’s impact was sufficiently large to be detected despite the smaller sample size for these outcomes.\u003c/p\u003e\n\n"},{"header":"Conclusion","content":"\u003cp\u003eThis intervention, which combined a simple WASH kit and hygiene promotion, was implemented with high fidelity and response, resulting in substantial reductions in microbial contamination of household drinking water. Its integration into the standard OTP led to a significant reduction in diarrhoea prevalence, addressing a key determinant of malnutrition. As diarrhoea both contributes to and exacerbates malnutrition, this integration may help disrupt the cycle between infection and malnutrition, ultimately improving child health outcomes. However, the residual water contamination underscores the need for broader improvements in community-level WASH infrastructure to ensure safe water access beyond the duration of SAM treatment. Policymakers should therefore consider embedding WASH interventions within nutrition programmes to enhance their impact, while also investing in sustainable, long-term solutions to address environmental health risks.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eUnited Nations Children\u0026rsquo;s Fund (UNICEF), World Health Organization (WHO), International Bank for Reconstruction and Development, The World Bank. Levels and trends in child malnutrition: UNICEF / WHO / World Bank Group Joint Child Malnutrition Estimates: Key findings of the 2023 edition 2023 [Available from: https://data.unicef.org/resources/jme-report-2023/.\u003c/li\u003e\n\u003cli\u003eBlack RE, Allen LH, Bhutta ZA, Caulfield LE, de Onis M, Ezzati M, et al. Maternal and child undernutrition: global and regional exposures and health consequences. The Lancet. 2008;371(9608):243-60.\u003c/li\u003e\n\u003cli\u003eIrena AH, Mwambazi M, Mulenga V. Diarrhea is a Major killer of Children with Severe Acute Malnutrition Admitted to Inpatient Set-up in Lusaka, Zambia. Nutrition Journal. 2011;10(1):110.\u003c/li\u003e\n\u003cli\u003eCollins S, Dent N, Binns P, Bahwere P, Sadler K, Hallam A. Management of severe acute malnutrition in children. Lancet. 2006;368(9551):1992-2000.\u003c/li\u003e\n\u003cli\u003eKyu HH, Vongpradith A, Dominguez R-MV, Ma J, Albertson SB, Novotney A, et al. Global, regional, and national age-sex-specific burden of diarrhoeal diseases, their risk factors, and aetiologies, 1990\u0026ndash;2021, for 204 countries and territories: a systematic analysis for the Global Burden of Disease Study 2021. The Lancet Infectious Diseases. 2024.\u003c/li\u003e\n\u003cli\u003eRosenberg IH, Solomons NW, Schneider RE. Malabsorption associated with diarrhea and intestinal infections. Am J Clin Nutr. 1977;30(8):1248-53.\u003c/li\u003e\n\u003cli\u003eWolf J, Hubbard S, Brauer M, Ambelu A, Arnold B, Bain R, et al. Effectiveness of interventions to improve drinking water, sanitation and handwashing with soap on diarrhoeal disease in children in low- and middle-income settings: a systematic review and meta-analysis 2022.\u003c/li\u003e\n\u003cli\u003eAltmann M, Altare C, van der Spek N, Barbiche JC, Dodos J, Bechir M, et al. 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Implementing a pragmatic randomised controlled trial in a humanitarian setting: lessons learned from the TISA trial. Trials. 2024;25(1):620.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"nature-portfolio","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Nature Portfolio","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"ejp","reportingPortfolio":"","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7506201/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7506201/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eSevere acute malnutrition (SAM) affects an estimated 17 million children globally and is increasingly treated at home under the Community-based Management of Acute Malnutrition (CMAM) approach. However, household environmental hazards, particularly unsafe drinking water, may undermine recovery. In the Traitement Intégré de la Sous-Nutrition Aiguë (TISA) cluster-randomised controlled trial in northern Senegal, children aged 6–59 months with uncomplicated SAM were enrolled in outpatient therapeutic programmes. The control group received the standard eight-week national protocol, while the intervention group also received chlorination tablets, a 20-litre storage container, soap, and hygiene promotion. This nested sub-study assessed the impact of the intervention on household water quality and diarrhoea. Among 445 households, drinking water samples collected 4–6 weeks after enrolment showed higher median free chlorine in the intervention group (0.5 mg/L, IQR 0.1–2.0) than controls (0.1 mg/L, IQR 0.1–0.1). \u003cem\u003eEscherichia coli\u003c/em\u003e contamination was reduced, with 46% of intervention samples classified as safe (\u0026lt;1 CFU/100 mL) versus 34% in the control. Diarrhoea prevalence declined over time in both groups, with a significantly greater reduction in the intervention arm (global Wald test p=0.028). The intervention substantially improved microbial drinking-water quality and was associated with lower diarrhoea prevalence among children receiving SAM treatment, though residual water contamination remained at levels posing moderate health risk. These findings highlight the potential for integrating targeted water treatment and hygiene measures into CMAM to reduce waterborne disease risk and diarrhoea among children with SAM.\u003c/p\u003e","manuscriptTitle":"Effect of a Water Treatment and Hygiene Intervention on Household Drinking Water Quality and Diarrhoea: A Sub-study of the TISA Trial in Senegal","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-15 09:06:11","doi":"10.21203/rs.3.rs-7506201/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-water","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"natwater","sideBox":"Learn more about [Nature Water](https://www.nature.com/natwater/)","snPcode":"44221","submissionUrl":"https://mts-natwater.nature.com/cgi-bin/main.plex","title":"Nature Water","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Research","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"b654a240-38f0-4858-b566-f703e5f8ef76","owner":[],"postedDate":"October 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":54008979,"name":"Health sciences/Diseases/Nutrition disorders/Malnutrition"},{"id":54008980,"name":"Health sciences/Health care/Health services"},{"id":54008981,"name":"Health sciences/Diseases/Gastrointestinal diseases/Intestinal diseases/Diarrhoea"},{"id":54008982,"name":"Scientific community and society/Water resources"}],"tags":[],"updatedAt":"2025-11-11T21:25:57+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-15 09:06:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7506201","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7506201","identity":"rs-7506201","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}