Cluster-randomised controlled trials of individual and combined water, sanitation, hygiene and nutritional interventions in rural Bangladesh and Kenya: the WASH Benefits study design and rationale

Rural revival: Navigating environmental engineering and technology

The necessity for global engineering and technological solutions to address rural environmental challenges is paramount, particularly in improving rural waste treatment and infrastructure. This study presents a comprehensive quantitative analysis of 3901 SCI/SSCI and 3818 Chinese CSCD papers, spanning from 1989 to 2021, using tools like Derwent Data Analyzer and VOSviewer. Our key findings reveal a significant evolution in research focus, including a 716.67% increase in global publications from 1995 to 2008 and a 154.76% surge from 2015 to 2021, highlighting a growing research interest with technological hotspots in rural revitalization engineering and agricultural waste recycling. China and the USA are pivotal, contributing 784 and 714 publications respectively. Prominent institutions such as the Chinese Academy of Sciences play a crucial role, particularly in fecal waste treatment technology. These insights advocate for enhanced policy development and practical implementations to foster inclusive and sustainable rural environments globally.

Addressing Fecal Contamination in Rural Kenyan Households: The Roles of Environmental Interventions and Animal Ownership

Combined water, sanitation, and handwashing (WSH) interventions could reduce fecal contamination along more transmission pathways than single interventions alone. We measured Escherichia coli levels in 3909 drinking water samples, 2691 child hand rinses, and 2422 toy ball rinses collected from households enrolled in a 2-year cluster-randomized controlled trial evaluating single and combined WSH interventions. Water treatment with chlorine reduced E. coli in drinking water. A combined WSH intervention improved water quality by the same magnitude but did not affect E. coli levels on hands or toys. One potential explanation for the limited impact of the sanitation intervention (upgraded latrines) is failure to address dog and livestock fecal contamination. Small ruminant (goat or sheep) ownership was associated with increased E. coli levels in stored water and on child hands. Cattle and poultry ownership was protective against child stunting, and domesticated animal ownership was not associated with child diarrhea. Our findings do not support restricting household animal ownership to prevent child diarrheal disease or stunting but do support calls for WSH infrastructure that can more effectively reduce household fecal contamination.

Associations between Shared Sanitation, Stunting and Diarrhoea in Low-Income, High Density Urban Neighbourhoods of Maputo, Mozambique - a Cross-Sectional Study

INTRODUCTION

Shared sanitation facilities are used by over 500 million people around the world. Most research evidence indicates that shared sanitation conveys higher risk than household sanitation for many adverse health outcomes. However, studies often fail to account for variation between different types of shared facilities. As informal housing development outpaces sanitation infrastructure, it is imperative to understand which components of shared facilities may mitigate the health risks of shared sanitation use.

METHODS

This cross-sectional study determines whether sanitation improvement or compound hygiene were associated with stunting or diarrhoeal prevalence in children under five living in Maputo, Mozambique who rely on shared sanitation facilities. The study uses logistic and linear multivariable regression analysis to search for associations and control for potential confounding factors.

RESULTS

346 children (43.9%) in the study population were stunted. Each unit increase in sanitation score was associated with an approximate decrease of 22% in the odds of stunting (OR: 0.78, CI: 0.66, 0.92), and an increase in height of 0.23 height-for-age z-scores (CI: 0.10, 0.36). There was no evidence that the compound hygiene score was associated with height as measured by stunting (OR: 1.05, CI: 0.87, 1.26) or z-score (-0.06, CI: -0.21, 0.09). Neither sanitation nor compound hygiene score were associated with diarrhoea in the population.

CONCLUSIONS

Use of an improved shared latrine is associated with decreased odds of stunting. There is no evidence of an association between latrine improvement and diarrhoea. Further investigation is necessary to isolate attributes of shared sanitation facilities that may reduce health risks.

Influence of Temperature and Precipitation on the Effectiveness of Water, Sanitation, and Handwashing Interventions against Childhood Diarrheal Disease in Rural Bangladesh: A Reanalysis of the WASH Benefits Bangladesh Trial

BACKGROUND

Diarrheal disease is a leading cause of childhood morbidity and mortality globally. Household water, sanitation, and handwashing (WASH) interventions can reduce exposure to diarrhea-causing pathogens, but meteorological factors may impact their effectiveness. Information about effect heterogeneity under different weather conditions is critical to refining these targeted interventions.

OBJECTIVES

We aimed to determine whether temperature and precipitation modified the effect of low-cost, point-of-use WASH interventions on child diarrhea.

METHODS

We analyzed data from a trial in rural Bangladesh that compared child diarrhea prevalence between clusters (N = 720 ) that were randomized to different WASH interventions between 2012 and 2016 (NCT01590095). We matched temperature and precipitation measurements to diarrhea outcomes (N = 12,440 measurements, 6,921 children) by geographic coordinates and date. We estimated prevalence ratios (PRs) using generative additive models and targeted maximum likelihood estimation to assess the effectiveness of each WASH intervention under different weather conditions.

RESULTS

Generally, WASH interventions most effectively prevented diarrhea during monsoon season, particularly following weeks with heavy rain or high temperatures. The PR for diarrhea in the WASH interventions group compared with the control group was 0.49 (95% CI: 0.35, 0.68) after 1 d of heavy rainfall, with a less-protective effect [PR = 0.87 (95% CI: 0.60, 1.25)] when there were no days with heavy rainfall. Similarly, the PR for diarrhea in the WASH intervention group compared with the control group was 0.60 (95% CI: 0.48, 0.75) following above-median temperatures vs. 0.91 (95% CI: 0.61, 1.35) following below-median temperatures. The influence of precipitation and temperature varied by intervention type; for precipitation, the largest differences in effectiveness were for the sanitation and combined WASH interventions.

DISCUSSION

WASH intervention effectiveness was strongly influenced by precipitation and temperature, and nearly all protective effects were observed during the rainy season. Future implementation of these interventions should consider local environmental conditions to maximize effectiveness, including targeted efforts to maintain latrines and promote community adoption ahead of monsoon seasons. https://doi.org/10.1289/EHP13807.

Multiple pathogen contamination of water, hands, and fomites in rural Nepal and the effect of WaSH interventions

Water, Sanitation, and Hygiene (WaSH) interventions are the most effective in reducing diarrheal disease severity and prevalence. However, very few studies have investigated the effectiveness of WaSH intervention in reducing pathogen presence and concentration. In this study, we employed a microfluidic PCR approach to quantify twenty bacterial pathogens in water (n = 360), hands (n = 180), and fomite (n = 540) samples collected in rural households of Nepal to assess the pathogen exposures and the effect of WaSH intervention on contamination and exposure rates. The pathogen load and the exposure pathways for each pathogen in intervention and control villages were compared to understand the effects of WaSH intervention. Pathogens were detected in higher frequency and concentration from fomites samples, toilet handle (21.42%; 5.4,0 95%CI: mean log10 of 4.69, 5.96), utensils (23.5%; 5.47, 95%CI: mean log10 of 4.77, 6.77), and water vessels (22.42%; 5.53, 95%CI: mean log10 of 4.79, 6.60) as compared to cleaning water (14.36%; 5.05, 95%CI: mean log10 of 4.36, 5.89), drinking water (14.26%; 4.37, 85%CI: mean log10 of 4.37, 5.87), and hand rinse samples (16.92%; 5.49, 95%CI: mean log10 of 4.77, 6.39). There was no clear evidence that WaSH intervention reduced overall pathogen contamination in any tested pathway. However, we observed a significant reduction (p < 0.05) in the prevalence, but not concentration, of some target pathogens, including Enterococcus spp. in the intervention village compared to the control village for water and hands rinse samples. Conversely, no significant reduction in target pathogen concentration was observed for water and hand rinse samples. In swab samples, there was a reduction mostly in pathogen concentration rather than pathogen prevalence, highlighting that a reduction in pathogen prevalence was not always accompanied by a reduction in pathogen concentration. This study provides an understanding of WaSH intervention on microbe concentrations. Such data could help with better planning of intervention activities in the future.

Treatment Heterogeneity of Water, Sanitation, Hygiene, and Nutrition Interventions on Child Growth by Environmental Enteric Dysfunction and Pathogen Status for Young Children in Bangladesh

Background

Water, sanitation, hygiene (WSH), nutrition (N), and combined (N+WSH) interventions are often implemented by global health organizations, but WSH interventions may insufficiently reduce pathogen exposure, and nutrition interventions may be modified by environmental enteric dysfunction (EED), a condition of increased intestinal permeability and inflammation. This study investigated the heterogeneity of these treatments' effects based on individual pathogen and EED biomarker status with respect to child linear growth.

Methods

We applied cross-validated targeted maximum likelihood estimation and super learner ensemble machine learning to assess the conditional treatment effects in subgroups defined by biomarker and pathogen status. We analyzed treatment (N+WSH, WSH, N, or control) randomly assigned in-utero, child pathogen and EED data at 14 months of age, and child LAZ at 28 months of age. We estimated the difference in mean child length for age Z-score (LAZ) under the treatment rule and the difference in stratified treatment effect (treatment effect difference) comparing children with high versus low pathogen/biomarker status while controlling for baseline covariates.

Results

We analyzed data from 1,522 children, who had median LAZ of -1.56. We found that myeloperoxidase (N+WSH treatment effect difference 0.0007 LAZ, WSH treatment effect difference 0.1032 LAZ, N treatment effect difference 0.0037 LAZ) and Campylobacter infection (N+WSH treatment effect difference 0.0011 LAZ, WSH difference 0.0119 LAZ, N difference 0.0255 LAZ) were associated with greater effect of all interventions on growth. In other words, children with high myeloperoxidase or Campylobacter infection experienced a greater impact of the interventions on growth. We found that a treatment rule that assigned the N+WSH (LAZ difference 0.23, 95% CI (0.05, 0.41)) and WSH (LAZ difference 0.17, 95% CI (0.04, 0.30)) interventions based on EED biomarkers and pathogens increased predicted child growth compared to the randomly allocated intervention.

Conclusions

These findings indicate that EED biomarker and pathogen status, particularly Campylobacter and myeloperoxidase (a measure of gut inflammation), may be related to impact of N+WSH, WSH, and N interventions on child linear growth.

Improved Child Feces Management Mediates Reductions in Childhood Diarrhea from an On-Site Sanitation Intervention: Causal Mediation Analysis of a Cluster-Randomized Trial in Rural Bangladesh

BACKGROUND

The WASH benefits Bangladesh trial multi-component sanitation intervention reduced diarrheal disease among children < 5 years. Intervention components included latrine upgrades, child feces management tools, and behavioral promotion. It remains unclear which components most impacted diarrhea.

METHODS

We conducted mediation analysis within a subset of households (n = 720) from the sanitation and control arms. Potential mediators were categorized into indicators of latrine quality, latrine use practices, and feces management practices. We estimated average causal mediation effects (ACME) as prevalence differences (PD), defined as the intervention's effect on diarrhea through its effect on the mediator.

RESULTS

The intervention improved all indicators compared to controls. We found significant mediation through multiple latrine use and feces management practice indicators. The strongest mediators during monsoon seasons were reduced open defecation among children aged < 3 and 3-8 years, and increased disposal of child feces into latrines. The strongest mediators during dry seasons were access to a flush/pour-flush latrine, reduced open defecation among children aged 3-8 years, and increased disposal of child feces into latrines. Individual mediation effects were small (PD = 0.5-2 percentage points) compared to the overall intervention effect but collectively describe significant mediation pathways.

DISCUSSION

The effect of the WASH Benefits Bangladesh sanitation intervention on diarrheal disease was mediated through improved child feces management and reduced child open defecation. Although the intervention significantly improved latrine quality, relatively high latrine quality at baseline may have limited benefits from additional improvements. Targeting safe child feces management may increase the health benefits of rural sanitation interventions.

Co-existence of maternal overweight/obesity, child undernutrition, and anaemia among mother-child pairs in Ethiopia

Ethiopia is currently known to be the most food-insecure country in sub-Saharan Africa, where childhood undernutrition remains endemic. While attention is increasingly being paid to childhood undernutrition in Ethiopia, a current surge of "triple burden of malnutrition" (TBM) has received less attention. The purpose of this study was to determine the prevalence of TBM and identify the associated factors in Ethiopia. Data were from the Ethiopian Demographic and Health Surveys (2005-2016) and a total of 20,994 mother-child pairs were examined in this study. The TBM was our primary outcome variable, which encompasses three types of nutritional problems-when a mother may be overweight/obese, while her child is stunted, wasted, or underweight plus has anaemia under the same roof. A multilevel logistic regression explored the individual- and community-level factors associated with TBM. Our study indicated that children under-five years of age were anaemic, stunted, wasted, and underweight [49.3% (95% CI: 48.7-49.9), 43.1% (95% CI: 42.4-43.7), 10.3% (95% CI: 9.9-10.7), and 27.6% (95% CI: 27.0-28.1)] respectively. The overall prevalence of TBM was 2.6% (95% CI: 2.39-2.83). Multilevel analyses revealed that TBM was more likely to occur among children aged 12-23 months (AOR: 2.54, 95% CI: 1.68-3.83), 24-35 months (AOR: 1.54, 95% CI: 1.03-2.29), children perceived by their mothers to be smaller than normal at birth (AOR: 1.94, 95% CI: 1.48-2.56), who experienced fever in the past 2 weeks (AOR: 1.58, 95% CI: 1.24-2.01), and lived in urban settings (AOR: 1.79, 95% CI: 1.13-2.86). Lower odds of TBM were reported among female children (AOR: 0.59, 95% CI: 0.47-0.72), and those who lived in rich households (AOR: 0.69: 95% CI: 0.49-0.98). TBM was found to be present in almost three percent of households in Ethiopia. Addressing the TBM through double-duty actions will be of critical importance in achieving malnutrition in all its forms in Ethiopia.

WASH interventions and child diarrhea at the interface of climate and socioeconomic position in Bangladesh

Many diarrhea-causing pathogens are climate-sensitive, and populations with the lowest socioeconomic position (SEP) are often most vulnerable to climate-related transmission. Household Water, Sanitation, and Handwashing (WASH) interventions constitute one potential effective strategy to reduce child diarrhea, especially among low-income households. Capitalizing on a cluster randomized trial population (360 clusters, 4941 children with 8440 measurements) in rural Bangladesh, one of the world's most climate-sensitive regions, we show that improved WASH substantially reduces diarrhea risk with largest benefits among children with lowest SEP and during the monsoon season. We extrapolated trial results to rural Bangladesh regions using high-resolution geospatial layers to identify areas most likely to benefit. Scaling up a similar intervention could prevent an estimated 734 (95% CI 385, 1085) cases per 1000 children per month during the seasonal monsoon, with marked regional heterogeneities. Here, we show how to extend large-scale trials to inform WASH strategies among climate-sensitive and low-income populations.

Geographic pair matching in large-scale cluster randomized trials

Cluster randomized trials are often used to study large-scale public health interventions. In large trials, even small improvements in statistical efficiency can have profound impacts on the required sample size and cost. Location integrates many socio-demographic and environmental characteristics into a single, readily available feature. Here we show that pair matching by geographic location leads to substantial gains in statistical efficiency for 14 child health outcomes that span growth, development, and infectious disease through a re-analysis of two large-scale trials of nutritional and environmental interventions in Bangladesh and Kenya. Relative efficiencies from pair matching are ≥1.1 for all outcomes and regularly exceed 2.0, meaning an unmatched trial would need to enroll at least twice as many clusters to achieve the same level of precision as the geographically pair matched design. We also show that geographically pair matched designs enable estimation of fine-scale, spatially varying effect heterogeneity under minimal assumptions. Our results demonstrate broad, substantial benefits of geographic pair matching in large-scale, cluster randomized trials.

Micronutrient status during pregnancy is associated with child immune status in rural Bangladesh

Background

Poor immune function increases children's risk of infection and mortality. Several maternal factors during pregnancy may affect infant immune function during the postnatal period.

Objectives

We aimed to evaluate whether maternal micronutrients, stress, estriol, and immune status during the first or second trimester of pregnancy were associated with child immune status in the first two years after birth.

Methods

We conducted observational analyses within the water, sanitation, and hygiene (WASH) Benefits Bangladesh randomized controlled trial. We measured biomarkers in 575 pregnant women and postnatally in their children. Maternal biomarkers measured during the first and second trimester of pregnancy included nutrition status via vitamin D (25-hydroxy-D [25(OH)D]), ferritin, soluble transferrin receptor (sTfR), and retinol-binding protein (RBP); cortisol; estriol. Immune markers were assessed in pregnant women at enrollment and their children at ages 14 and 28 mo, including C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP), and 13 cytokines (including IFN-γ). We generated a standardized sum score of log-transformed cytokines. We analyzed IFN-γ individually because it is a critical immunoregulatory cytokine. All outcomes were prespecified. We used generalized additive models and reported the mean difference and 95% confidence intervals at the 25th and 75th percentiles of exposure distribution.

Results

At child age 14 mo, concentrations of maternal RBP were inversely associated with the cytokine sum score in children (-0.34 adjusted difference between the 25th and 75th percentile [95% confidence interval -0.61, -0.07]), and maternal vitamin A deficiency was positively associated with the cytokine sum score in children (1.02 [0.13, 1.91]). At child age of 28 mo, maternal RBP was positively associated with IFN-γ in children (0.07 [0.01, 0.14]), whereas maternal vitamin A deficiency was negatively associated with child AGP (-0.07 [-0.13, -0.02]). Maternal iron deficiency was associated with higher AGP concentrations in children at age 14 mo (0.13 [0.04, 0.23]), and maternal sTfR concentrations were positively associated with child CRP concentrations at age 28 mo (0.18 [0, 0.36]).

Conclusion

Maternal deficiencies in vitamin A or iron during the first 2 trimesters of pregnancy may shape the trajectory of a child's immune status.

Interpreting alignment to the EAT-Lancet diet using dietary intakes of lactating mothers in rural Western Kenya

The EAT-Lancet reference diet intends to be good for planetary and human health. We compared single multiple pass method 24-h dietary intake of mothers (n = 242) from a cross-sectional study in Western Kenya to the recommended range of intake of 11 EAT-Lancet food groups (e.g., 0-100 g/day legumes; maximum score 11), defining alignment two ways: daily intake among food groups where a minimum intake of 0 g was either acceptable or unacceptable. Ordinal logistic regression models assessed associations between alignment and body mass index (BMI). Cost of mothers' diets and hypothetical diets within recommended ranges (lower bounds >0 g) were estimated using food price data from markets within the mothers' locality. Mean energy intake was 1827 (95% confidence interval [CI]: 1731-1924) kcal/day. Relative to the EAT-Lancet diet, mothers' diets were on average higher for grains; within recommendations for tubers, fish, beef and dairy; closer to lower bounds for chicken, eggs, legumes and nuts; and lower for fruits and vegetables. Mean (95% CI) alignment scores were 8.2 (8.0-8.3) when 0 g intakes were acceptable and 1.7 (1.6-1.9) otherwise. No significant associations were found between alignment and BMI. Mothers' diets and hypothetical diets within recommended ranges averaged 184.6 KES (1.6 USD) and 357.5 KES (3.0 USD)/person/day, respectively. Lactating mothers' diets were not diverse and diverged from the reference diet when an intake of 0 g was considered unacceptable. Lower bound intakes of 0 g for micronutrient-dense food groups are inappropriate in food-insecure populations. It would likely cost more than mothers currently spend to tailor their diets to the EAT-Lancet reference diet.

Geographic pair-matching in large-scale cluster randomized trials

Custer randomized trials are often used to study large-scale public health interventions. In large trials, even small improvements in statistical efficiency can have profound impacts on the required sample size and cost. Pair matched randomization is one strategy with potential to increase trial efficiency, but to our knowledge there have been no empirical evaluations of pair-matching in large-scale, epidemiologic field trials. Location integrates many socio-demographic and environmental characteristics into a single feature. Here, we show that geographic pair-matching leads to substantial gains in statistical efficiency for 14 child health outcomes that span growth, development, and infectious disease through a re-analysis of two large-scale trials of nutritional and environmental interventions in Bangladesh and Kenya. We estimate relative efficiencies ≥1.1 for all outcomes assessed and relative efficiencies regularly exceed 2.0, meaning an unmatched trial would have needed to enroll at least twice as many clusters to achieve the same level of precision as the geographically pair-matched design. We also show that geographically pair-matched designs enable estimation of fine-scale, spatially varying effect heterogeneity under minimal assumptions. Our results demonstrate broad, substantial benefits of geographic pair-matching in large-scale, cluster randomized trials.

Effects of High Temperature and Heavy Precipitation on Drinking Water Quality and Child Hand Contamination Levels in Rural Kenya

Climate change may impact human health through the influence of weather on environmental transmission of diarrhea. Previous studies have found that high temperatures and heavy precipitation are associated with increased diarrhea prevalence, but the underlying causal mechanisms have not been tested and validated. We linked measurements of Escherichia coli in source water (n = 1673), stored drinking water (n = 9692), and hand rinses from children <2 years old (n = 2634) with publicly available gridded temperature and precipitation data (at ≤0.2 degree spatial resolution and daily temporal resolution) by the GPS coordinates and date of sample collection. Measurements were collected over a 3-year period across a 2500 km² area in rural Kenya. In drinking water sources, high 7-day temperature was associated with a 0.16 increase in log₁₀ E. coli levels (p < 0.001, 95% CI: 0.07, 0.24), while heavy 7-day total precipitation was associated with a 0.29 increase in log₁₀ E. coli levels (p < 0.001, 95% CI: 0.13, 0.44). In household stored drinking water, heavy 7-day precipitation was associated with a 0.079 increase in log₁₀ E. coli levels (p = 0.042, 95% CI: 0.07, 0.24). Heavy precipitation did not increase E. coli levels among respondents who treated their water, suggesting that water treatment can mitigate effects on water quality. On child hands, high 7-day temperature was associated with a 0.39 decrease in log₁₀ E. coli levels (p < 0.001, 95% CI: -0.52, -0.27). Our findings provide insight on how climate change could impact environmental transmission of bacterial pathogens in Kenya. We suggest water treatment is especially important after heavy precipitation (particularly when preceded by dry periods) and high temperatures.

Outcome evaluation of WASH intervention in rural households at Jawi district, Northwest Ethiopia: Mixed method design, goal based evaluation

BACKGROUND

The government of Ethiopia revealed that GTP II and SDG were achieved through one Water Sanitation and Hygiene (WASH) program. According to the 2016 Ethiopian Demographic and Health survey, the rural population was more affected by poor sanitation and hygiene. To address this Ethiopian government ratified Rural WASH sanitation and hygiene promotion through a community-centered approach, and to improve WASH service evidence on the effectiveness of an intervention at the household level is needed in developing countries. However, in our country one WASH in rural areas called community centered approach intervention was planned and delivered for 3 years (2018-2020) Nevertheless, as to our review and researchers knowledge, the outcome of this intervention is not evaluated yet in our country as well as in this evaluation study area.

METHOD

The evaluation was conducted in rural households of Jawi district by a Quasi-experimental design supplemented with a qualitative in-depth interview, from 01/14/2021-3/28/2021 and 4/22/2021-5/25/2021 for quanitative and qualitative study, respectively. Intervention groups were households that took WASH intervention while the controls did not. The evaluation approach was summative and counterfactual plus participatory and focuses on program outcome. A total of 1280 households were selected using two stage sampling with lottery method simple random sampling. We collected quantitative data through survey and structured observational checklist, while qualitative data through key informant interviews using a semi-structured questionnaire. We assessed program effectiveness and also the analytical study was conducted through propensity score matching to assess program effect through Stata 14.1. Qualitative data were transcribed and translated to English and thematic analysis was done using Atlas.ti.9.

RESULT

The overall program effectiveness was very good but the effectiveness in handwashing before eating using soap and water was poor. Also, this intervention increased water treatment utilization in 41.7% point (ATT=0.417, 95% CI= 0.356, 0.478), 24.3% point (ATT =0.243, 95%CI=0.180, 0.300) in exclusive latrine utilization, 41.9% point (ATT=0.419, 95%CI = 0.376, 0.470) in handwashing using water and soap before eating, 50.2% point(ATT=0.502, 95%CI=0.450, 0.550) in handwashing after defecation by using water and soap in intervention households. Our qualitative finding revealed that unable to afford soap and their working place far away from their home were the most frequent reason reported by the respondent for not using soap for hand washing and latrine utilization respectively CONCLUSIONS: This intervention should be scale-up and pay greater attention and deliver innovative strategies to the improvement of handwashing practice and exclusive latrine utilization.

AVAILABILITY OF DATA AND MATERIALS

The data sets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Prevalence and multi-level factors associated with acute malnutrition among children aged 6-59 months from war affected communities of Tigray, Northern Ethiopia, 2021: a cross-sectional study

BACKGROUND

Armed conflicts greatly affect the health, nutrition, and food security of conflict affected settings particularly children. However, no empirical data exist regarding context specific factors contributing towards acute malnutrition in the war-torn Tigray, Ethiopia. Thus, this study aimed to identify individual and community level factors associated with acute malnutrition among children aged 6-59 months from armed conflict affected settings of Tigray, Ethiopia.

METHODS

A community based cross-sectional study was conducted among 3,614 children aged 6-59 months in Tigray, from July 15 to Aug 15, 2021. Study participants were selected using a two-stage random sampling method. A structured questionnaire was used to collect data by interviewing mothers/caregivers. Mid upper arm circumference (MUAC) measurements were taken from upper left arm of the children using MUAC tapes. Multivariable multilevel logistic regression analysis was used to determine factors associated with acute malnutrition. Adjusted Odds ratio (AOR) with 95% CI were estimated to describe the strength of associations at p < 0.05.

RESULTS

More than half (52.5%) of the sampled children were males in sex. Immediately after the first nine months into the conflict, the prevalence of severe, moderate, and global acute malnutrition was very high (5.1%, 21.8%, and 26.9%, respectively) in Tigray. The lowest and highest burden of child acute malnutrition was reported from Mekelle zone (13.3%) and Southeastern zone (36.7%), respectively. Individual-level factors such as older child age (AOR = 0.13, 95% CI: 0.10, 0.18), female child sex (AOR = 1.24, 95% CI 1.05, 1.480.95), Vitamin-A supplementation (AOR = 1.3, 95% CI: 1.05, 1.65), and history of diarrhea (AOR = 1.22, 95%CI: 1.02, 1.53) and community-level factors like unimproved drinking water source (AOR = 1.31, 95%CI: 1.08, 1.58), unimproved toilet facility (AOR = 1.24, 95% CI: 1.01, 1.52), and severe food insecurity (AOR = 1.55, 95% CI: 1.16. 2.07) were significantly associated with childhood acute malnutrition.

CONCLUSIONS

The burden of acute malnutrition is a severe public health problem in Tigray. To prevent the untimely suffering and death of children, regular nutrition screening, speedy, and appropriate referral of all malnourished children to nutritional services and large-scale humanitarian assistance including access to food; nutrition supplies; water, sanitation and hygiene supplies; and health care in a timely manner are required. In the prevailing armed conflict, these have been very difficult to achieve. Thus, immediate international intervention is needed.

Assessing sustained uptake of latrine and child feces management interventions: Extended follow-up of a cluster-randomized controlled trial in rural Bangladesh 1-3.5 years after intervention initiation

BACKGROUND

Sanitation interventions typically result in modest increases in latrine access, and any gains in latrine access and use are often not sustained over time. Sanitation programs also rarely include child-focused interventions such as potties. We aimed to assess the sustained effect of a multi-component sanitation intervention on access to and use of latrines and child feces management tools in rural Bangladesh.

METHODS

We conducted a longitudinal substudy nested within the WASH Benefits randomized controlled trial. The trial provided latrine upgrades, child potties and sani-scoops for feces removal, along with behavior change promotion to encourage use of the delivered hardware. Promotion visits to intervention recipients were frequent during the first 2 years after intervention initiation, decreased in frequency between years 2-3, and ceased after 3 years. We enrolled a random subset of 720 households from the sanitation and control arms of the trial in a substudy and visited them quarterly between 1 and 3.5 years after intervention initiation. At each visit, field staff recorded sanitation-related behaviors through spot-check observations and structured questionnaires. We assessed intervention effects on observed indicators of hygienic latrine access, potty use and sani-scoop use and investigated whether these effects were modified by duration of follow-up, ongoing behavior change promotion and household characteristics.

RESULTS

The intervention increased hygienic latrine access from 37% among controls to 94% in the sanitation arm (p < 0.001). Access among intervention recipients remained high 3.5 years after intervention initiation, including periods with no active promotion. Gains in access were higher among households with less education, less wealth and larger number of residents. The intervention increased availability of child potties from 29% among controls to 98% in the sanitation arm (p < 0.001). However, fewer than 25% of intervention households reported exclusive child defecation in a potty or had observed indicators of potty and sani-scoop use, and gains in potty use declined over the follow-up period, even with ongoing promotion.

CONCLUSION

Our findings from an intervention that provided free products and intensive initial behavior change promotion suggest a sustained increase in hygienic latrine access up to 3.5 years after intervention initiation but infrequent use of child feces management tools. Studies should investigate strategies to ensure sustained adoption of safe child feces management practices.

Physical interventions to interrupt or reduce the spread of respiratory viruses

BACKGROUND

Viral epidemics or pandemics of acute respiratory infections (ARIs) pose a global threat. Examples are influenza (H1N1) caused by the H1N1pdm09 virus in 2009, severe acute respiratory syndrome (SARS) in 2003, and coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 in 2019. Antiviral drugs and vaccines may be insufficient to prevent their spread. This is an update of a Cochrane Review last published in 2020. We include results from studies from the current COVID-19 pandemic.

OBJECTIVES

To assess the effectiveness of physical interventions to interrupt or reduce the spread of acute respiratory viruses.

SEARCH METHODS

We searched CENTRAL, PubMed, Embase, CINAHL, and two trials registers in October 2022, with backwards and forwards citation analysis on the new studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cluster-RCTs investigating physical interventions (screening at entry ports, isolation, quarantine, physical distancing, personal protection, hand hygiene, face masks, glasses, and gargling) to prevent respiratory virus transmission.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures.

MAIN RESULTS

We included 11 new RCTs and cluster-RCTs (610,872 participants) in this update, bringing the total number of RCTs to 78. Six of the new trials were conducted during the COVID-19 pandemic; two from Mexico, and one each from Denmark, Bangladesh, England, and Norway. We identified four ongoing studies, of which one is completed, but unreported, evaluating masks concurrent with the COVID-19 pandemic. Many studies were conducted during non-epidemic influenza periods. Several were conducted during the 2009 H1N1 influenza pandemic, and others in epidemic influenza seasons up to 2016. Therefore, many studies were conducted in the context of lower respiratory viral circulation and transmission compared to COVID-19. The included studies were conducted in heterogeneous settings, ranging from suburban schools to hospital wards in high-income countries; crowded inner city settings in low-income countries; and an immigrant neighbourhood in a high-income country. Adherence with interventions was low in many studies. The risk of bias for the RCTs and cluster-RCTs was mostly high or unclear. Medical/surgical masks compared to no masks We included 12 trials (10 cluster-RCTs) comparing medical/surgical masks versus no masks to prevent the spread of viral respiratory illness (two trials with healthcare workers and 10 in the community). Wearing masks in the community probably makes little or no difference to the outcome of influenza-like illness (ILI)/COVID-19 like illness compared to not wearing masks (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.84 to 1.09; 9 trials, 276,917 participants; moderate-certainty evidence. Wearing masks in the community probably makes little or no difference to the outcome of laboratory-confirmed influenza/SARS-CoV-2 compared to not wearing masks (RR 1.01, 95% CI 0.72 to 1.42; 6 trials, 13,919 participants; moderate-certainty evidence). Harms were rarely measured and poorly reported (very low-certainty evidence). N95/P2 respirators compared to medical/surgical masks We pooled trials comparing N95/P2 respirators with medical/surgical masks (four in healthcare settings and one in a household setting). We are very uncertain on the effects of N95/P2 respirators compared with medical/surgical masks on the outcome of clinical respiratory illness (RR 0.70, 95% CI 0.45 to 1.10; 3 trials, 7779 participants; very low-certainty evidence). N95/P2 respirators compared with medical/surgical masks may be effective for ILI (RR 0.82, 95% CI 0.66 to 1.03; 5 trials, 8407 participants; low-certainty evidence). Evidence is limited by imprecision and heterogeneity for these subjective outcomes. The use of a N95/P2 respirators compared to medical/surgical masks probably makes little or no difference for the objective and more precise outcome of laboratory-confirmed influenza infection (RR 1.10, 95% CI 0.90 to 1.34; 5 trials, 8407 participants; moderate-certainty evidence). Restricting pooling to healthcare workers made no difference to the overall findings. Harms were poorly measured and reported, but discomfort wearing medical/surgical masks or N95/P2 respirators was mentioned in several studies (very low-certainty evidence).  One previously reported ongoing RCT has now been published and observed that medical/surgical masks were non-inferior to N95 respirators in a large study of 1009 healthcare workers in four countries providing direct care to COVID-19 patients.  Hand hygiene compared to control Nineteen trials compared hand hygiene interventions with controls with sufficient data to include in meta-analyses. Settings included schools, childcare centres and homes. Comparing hand hygiene interventions with controls (i.e. no intervention), there was a 14% relative reduction in the number of people with ARIs in the hand hygiene group (RR 0.86, 95% CI 0.81 to 0.90; 9 trials, 52,105 participants; moderate-certainty evidence), suggesting a probable benefit. In absolute terms this benefit would result in a reduction from 380 events per 1000 people to 327 per 1000 people (95% CI 308 to 342). When considering the more strictly defined outcomes of ILI and laboratory-confirmed influenza, the estimates of effect for ILI (RR 0.94, 95% CI 0.81 to 1.09; 11 trials, 34,503 participants; low-certainty evidence), and laboratory-confirmed influenza (RR 0.91, 95% CI 0.63 to 1.30; 8 trials, 8332 participants; low-certainty evidence), suggest the intervention made little or no difference. We pooled 19 trials (71, 210 participants) for the composite outcome of ARI or ILI or influenza, with each study only contributing once and the most comprehensive outcome reported. Pooled data showed that hand hygiene may be beneficial with an 11% relative reduction of respiratory illness (RR 0.89, 95% CI 0.83 to 0.94; low-certainty evidence), but with high heterogeneity. In absolute terms this benefit would result in a reduction from 200 events per 1000 people to 178 per 1000 people (95% CI 166 to 188). Few trials measured and reported harms (very low-certainty evidence). We found no RCTs on gowns and gloves, face shields, or screening at entry ports.

AUTHORS' CONCLUSIONS

The high risk of bias in the trials, variation in outcome measurement, and relatively low adherence with the interventions during the studies hampers drawing firm conclusions. There were additional RCTs during the pandemic related to physical interventions but a relative paucity given the importance of the question of masking and its relative effectiveness and the concomitant measures of mask adherence which would be highly relevant to the measurement of effectiveness, especially in the elderly and in young children. There is uncertainty about the effects of face masks. The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect. The pooled results of RCTs did not show a clear reduction in respiratory viral infection with the use of medical/surgical masks. There were no clear differences between the use of medical/surgical masks compared with N95/P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection. Hand hygiene is likely to modestly reduce the burden of respiratory illness, and although this effect was also present when ILI and laboratory-confirmed influenza were analysed separately, it was not found to be a significant difference for the latter two outcomes. Harms associated with physical interventions were under-investigated. There is a need for large, well-designed RCTs addressing the effectiveness of many of these interventions in multiple settings and populations, as well as the impact of adherence on effectiveness, especially in those most at risk of ARIs.

Leveraging infectious disease models to interpret randomized controlled trials: Controlling enteric pathogen transmission through water, sanitation, and hygiene interventions

Randomized controlled trials (RCTs) evaluate hypotheses in specific contexts and are often considered the gold standard of evidence for infectious disease interventions, but their results cannot immediately generalize to other contexts (e.g., different populations, interventions, or disease burdens). Mechanistic models are one approach to generalizing findings between contexts, but infectious disease transmission models (IDTMs) are not immediately suited for analyzing RCTs, since they often rely on time-series surveillance data. We developed an IDTM framework to explain relative risk outcomes of an infectious disease RCT and applied it to a water, sanitation, and hygiene (WASH) RCT. This model can generalize the RCT results to other contexts and conditions. We developed this compartmental IDTM framework to account for key WASH RCT factors: i) transmission across multiple environmental pathways, ii) multiple interventions applied individually and in combination, iii) adherence to interventions or preexisting conditions, and iv) the impact of individuals not enrolled in the study. We employed a hybrid sampling and estimation framework to obtain posterior estimates of mechanistic parameter sets consistent with empirical outcomes. We illustrated our model using WASH Benefits Bangladesh RCT data (n = 17,187). Our model reproduced reported diarrheal prevalence in this RCT. The baseline estimate of the basic reproduction number R 0 for the control arm (1.10, 95% CrI: 1.07, 1.16) corresponded to an endemic prevalence of 9.5% (95% CrI: 7.4, 13.7%) in the absence of interventions or preexisting WASH conditions. No single pathway was likely able to sustain transmission: pathway-specific R 0 s for water, fomites, and all other pathways were 0.42 (95% CrI: 0.03, 0.97), 0.20 (95% CrI: 0.02, 0.59), and 0.48 (95% CrI: 0.02, 0.94), respectively. An IDTM approach to evaluating RCTs can complement RCT analysis by providing a rigorous framework for generating data-driven hypotheses that explain trial findings, particularly unexpected null results, opening up existing data to deeper epidemiological understanding.

Food, water, and sanitation insecurities: Complex linkages and implications for achieving WASH security

Food, water and sanitation insecurities are complex, multi-dimensional phenomena that entail more than availability and access; food, water, and sanitation resources must be safe and culturally appropriate. Researchers and implementers concerned with these insecurities have demonstrated that there are notable interactions between them resulting in significant psychological and biological outcomes. Recent randomised controlled trials (RCTs) in Bangladesh, Kenya (WASH Benefits) and Zimbabwe (SHINE) demonstrated no effect from water, sanitation and hygiene (WASH) interventions on linear growth, and mixed evidence on enteropathogen burden and risk of diarrhoea in young children. These data suggest a need for a more comprehensive understanding of WASH security. The risks posed by multiple resource insecurities shift depending on the individual, their movement throughout their day, their economically and socially prescribed roles, and ecological features such as seasonality and precipitation. By more fully integrating food, water and sanitation security in interventions and subsequent impact evaluations, we can achieve WASH security-one that addresses myriad transmission pathways and co-occurring diseases-that ultimately would improve health outcomes throughout the world. In this critical review, we outline the complexity of combined resource insecurities as a step towards transformative WASH.

Fish and Fish-Based Products for Nutrition and Health in the First 1000 Days: A Systematic Review of the Evidence from Low and Middle-Income Countries

Fish provide essential nutrients for the critical window of growth and development in the first 1000 d of life and are thus an attractive option for inclusion in nutrition-sensitive and nutrition-specific programming. We conducted a systematic review of the evidence for fish and fish-based products for nutrition and health outcomes during the first 1000 d of life in low- and middle-income countries, searching the peer-reviewed and gray literature from 1999 to 2020. Databases included PubMed, Web of Science, Embase, ProQuest, and the Clinical Trials repository. Our search returned 1135 articles, 39 of which met the inclusion criteria. All studies were dual evaluated for risk of bias. Of the included studies, 18 measured maternal health and nutrition outcomes and 24 measured infant/child outcomes (3 measured both). Our search uncovered 10 impact evaluations, all of which measured consumption of fish or fish-based complementary food products in children aged 6-24 mo. We did not find strong evidence for fish consumption in children improving child growth from the impact evaluations; however, the studies were highly heterogeneous in their design and likely underpowered to detect an effect. Results from observational studies were mixed but provided evidence that adding fish to maternal and child diets is associated with improved nutrition outcomes, such as reducing the risk of anemia and improving vitamin D status. Given the nutrient richness of fish and the fact that production is often more environmentally friendly as compared with other animal source foods, more robust evidence is needed on the role of fish consumption in nutrition interventions to inform policy and programming recommendations in low- and middle-income countries.

Does a school-based intervention to engage parents change opportunity for handwashing with soap at home? Practical experience from the Mikono Safi trial in Northwestern Tanzania

BACKGROUND

School-based de-worming is advocated as a strategy for reducing the burden of soil-transmitted helminth (STH) infections among children. However, re-infection tends to occur rapidly, suggesting that comprehensive water, sanitation, and hygiene (WASH) improvements may be needed to prevent this. We qualitatively assessed the influence of parental engagement activities on parents' motivation to improve WASH infrastructure and hygiene practices at home in the context of a school-based de-worming programme.

METHODOLOGY

We conducted a longitudinal qualitative study nested within the Mikono Safi trial, designed to assess the effect of a WASH intervention on STH infection prevalence in children. Meetings were organized for parents/guardians at schools where they were given information about STH infection, the role of WASH in STH infection prevention, and actionable steps they could take at home. During the meetings, parents/guardians received information about their own child's STH infection status. Twenty purposively selected households were visited and interviewed 3 times over a period of about 8-months. We employed thematic analysis; findings are reported following the Capability-Opportunity-Motivation and Behaviour (COM-B) framework.

PRINCIPAL FINDINGS

The engagement strategy improved parents'/guardians' knowledge and skills about handwashing with soap and its benefits. Parents/guardians reported that the sessions had motivated them to improve WASH infrastructure at home. Of 20 households included in this study, 17 renovated or built new latrines and 18 installed handwashing facilities. However, only 8 households established and maintained handwashing stations with both soap and water at 8 months.

CONCLUSIONS

The engagement of parents/guardians in a school-based WASH education intervention as part of the Mikono Safi trial resulted in increased knowledge and motivation about handwashing and sanitation. This led to improvements in sanitation facilities and handwashing opportunities at home. However, long-term success in provision of water and soap was limited, indicating that sustained engagement may be required to encourage households to ensure these materials are consistently available at home.

Chlorine taste can increase simulated exposure to both fecal contamination and disinfection byproducts in water supplies

Expanding drinking water chlorination could substantially reduce the burden of disease in low- and middle-income countries, but the taste of chlorinated water often impedes adoption. We developed a Monte Carlo simulation to estimate the effect of people's choice to accept or reject drinking water based on chlorine taste and their subsequent exposure to E. coli and trihalomethanes, a class of disinfection byproduct (DBP). The simulation used empirical data from Dhaka, Bangladesh, a megacity with endemic waterborne disease. We drew on published taste acceptability thresholds from Dhaka residents, measured residual chlorine and thermotolerant E. coli inactivation following the addition of six chlorine doses (0.25-3.0 mg/L as Cl₂) to untreated piped water samples from 100 locations, and analyzed trihalomethane formation in 54 samples. A dose of 0.5 mg/L, 75% lower than the 2 mg/L dose typically recommended for household chlorination of low-turbidity waters, minimized overall exposure to E. coli. Doses of 1-2 mg/L maximized overall exposure to trihalomethanes. Accounting for chlorine taste aversion indicates that microbiological exposure increases and DBP exposure decreases above certain doses as a higher proportion of people reject chlorinated water in favor of untreated water. Taken together with findings from other modeling analyses, empirical studies, and field trials, our results suggest that taste acceptability should be a critical consideration in establishing chlorination dosing guidelines. Particularly when chlorination is first implemented in water supplies with low chlorine demand, lower doses than those generally recommended for household water treatment can help avoid taste-related objections while still meaningfully reducing contaminant exposure.

Effect of digestion on stability of palivizumab IgG1 in the infant gastrointestinal tract

BACKGROUND

Potentially, orally administered antibodies specific to enteric pathogens could be administered to infants to prevent diarrheal infections, particularly in developing countries where diarrhea is a major problem. However, to prevent infection, such antibodies would need to resist degradation within the gastrointestinal tract.

METHODS

Palivizumab, a recombinant antibody specific to respiratory syncytial virus (RSV), was used in this study as a model for examining the digestion of neutralizing antibodies to enteric pathogens in infants. The survival of this recombinant IgG1 across digestion in 11 infants was assayed via an anti-idiotype ELISA and RSV F protein-specific ELISA. Concentrations were controlled for any dilution or concentration that occurred in the digestive system using mass spectrometry-based quantification of co-administered, orally supplemented, indigestible polyethylene glycol (PEG-28).

RESULTS

Binding activity of Palivizumab IgG1 decreased (26-99%) across each phase of in vivo digestion as measured by both anti-idiotype and RSV F protein-specific ELISAs.

CONCLUSION

Antibodies generated for passive protection of the infant gastrointestinal tract from pathogens will need to be more resistant to digestion than the model antibody fed to infants in this study, or provided in higher doses to be most effective.

IMPACT

Binding activity of palivizumab IgG1 decreased (26-99%) across each phase of in vivo infant digestion as measured by both anti-idiotype and RSV F protein-specific ELISAs. Palivizumab was likely degraded by proteases and changes in pH introduced in the gut. Antibodies generated for passive protection of the infant gastrointestinal tract from pathogens will need to be more resistant to digestion than the model antibody fed to infants in this study, or provided in higher doses to be most effective. The monoclonal antibody IgG1 tested was not stable across the infant gastrointestinal tract. The observation of palivizumab reduction was unlikely due to dilution in the gastrointestinal tract. The results of this work hint that provision of antibody could be effective in preventing enteric pathogen infection in infants. Orally delivered recombinant antibodies will need to either be dosed at high levels to compensate for digestive losses or be engineered to better resist digestion. Provision of enteric pathogen-specific recombinant antibodies to at-risk infants could provide a new and previously unexplored pathway to reducing the infection in infants. The strategy of enteric recombinant antibodies deserves more investigation throughout medicine as a novel means for treatment of enteric disease targets.

Effect of sanitation improvements on soil-transmitted helminth eggs in courtyard soil from rural Bangladesh: Evidence from a cluster-randomized controlled trial

Improved sanitation has been hypothesized to reduce soil-transmitted helminth (STH) infections by reducing the prevalence and concentration of STH eggs/larvae in soil. We evaluated the effect of a randomized sanitation program (providing households with an improved dual-pit latrine, tools for child/animal feces management, and behavioral messaging) on reducing the prevalence and concentration of STH eggs in soil from household courtyards. We collected soil samples from 1405 households enrolled in the sanitation intervention (n = 419) and control (n = 914) groups of a cluster-randomized controlled trial (WASH Benefits) in rural Bangladesh approximately 2 years after the initiation of the interventions. We analyzed samples for Ascaris lumbricoides, Trichuris trichiura, and hookworm eggs by microscopy. We estimated prevalence ratios (PR) and egg count ratio (ECR) to compare the prevalence of STH eggs and arithmetic and geometric mean egg counts for STH eggs per gram of soil in the sanitation and control arms. Among intervention households, latrines achieved high and sustained user uptake by adults while child open defecation remained common and most households did not dispose of child feces hygienically. In courtyard soil from control households, the prevalence of any STH eggs was 75.7% and the prevalence of any larvated STH eggs was 67.3%. A. lumbricoides was detected in 63.0% of control samples and T. trichiura in 55.7% of control samples; hookworm was not detected in any sample. In the control arm, the arithmetic mean egg count for any STH was 3.96 eggs/dry gram, while the geometric mean was 1.58 eggs/dry gram. There was no difference between the intervention and control groups in the prevalence of any STH eggs (PR = 0.98 (95% CI: 0.91, 1.05)) or mean egg counts (ECR = 0.08 (95% CI: -0.10, 0.26) for geometric mean and 0.07 (95% CI: -0.22, 0.37) for arithmetic mean). Adjusted models gave similar results. A compound-level sanitation intervention that provided improved latrines and tools for disposal of child and animal feces did not have an impact on STH eggs in soil. In order to effectively reduce the prevalence and concentration of STH eggs in the environment, sustained, widespread use of sanitation strategies to isolate and hygienically dispose of child and animal feces may need to complement traditional strategies for containment of adult human feces. Trial Registration: NCT01590095.

Longitudinal Effects of a Sanitation Intervention on Environmental Fecal Contamination in a Cluster-Randomized Controlled Trial in Rural Bangladesh

Household latrine access generally is not associated with reduced fecal contamination in the environment, but its long-term effectiveness has not been measured. We conducted an environmental assessment nested within the WASH Benefits Bangladesh randomized controlled trial (NCT01590095). We quantified E. coli and fecal coliforms in samples of stored drinking water, child hands, mother hands, soil, and food among a random sample of households from the sanitation and control arms of the trial. Samples were collected during eight quarterly visits approximately 1-3.5 years after intervention initiation. Overall, there were no substantial differences in environmental fecal contamination between households enrolled in the sanitation and control arms. Statistically significant reductions were found in stored water and child hands after pooling across sampling rounds, but the effects were small and not consistent across rounds. In addition, we assessed potential effect modification of intervention effects by follow-up time, season, wealth, community-level latrine density and coverage, population density, and domestic animal ownership. While the intervention had statistically significant effects within some subgroups, there were no consistent patterns of effect modification. Our findings support a growing consensus that on-site latrines are insufficient to prevent fecal contamination in the rural household environment.

The role of chicken management practices in children's exposure to environmental contamination: a mixed-methods analysis

BACKGROUND

Household chicken production presents an opportunity to promote child nutrition, but the benefits might be offset by increased environmental contamination. Using household surveys, direct observations, and in-depth interviews with woman caregivers, we sought to describe the relationship between chicken management practices and household exposure to environmental contamination, and assess barriers to adopting improved husbandry practices.

METHODS

First, we analyzed baseline data from 973 households raising chickens in the two interventions arms from the Agriculture-to-Nutrition (ATONU) study in Ethiopia to assess the relationship between animal management practices and environmental exposures. Second, we conducted six-hour direct observations of children's environmental exposures in 18 households. Among these households, we analyzed in-depth interviews with child caregivers.

RESULTS

Quantitative analyses showed that households raised approximately 11 chickens, had animal feces visible on the property 67% of the time, and children's hands were visibly dirty 38% of the time. Households with more chickens had lower exposure to animal feces. Having a chicken coop increased the risk of observing animal feces on the property by 30%, but among those with a coop, having an enclosed coop reduced that risk by 83%. Coops that were enclosed, had fencing, and were located further from homes were associated with a reduced risk of observing animal feces and an increased likelihood of children having clean hands. Direct observations showed that chicken coops were often poorly designed or not used. On average, 3 to 5 chickens were inside homes at a time, and livestock and domestic animals were frequently inside of houses and interacting with young children. In-depth interviews revealed that protection of animals, maintenance of household cleanliness and health, type of chicken (local versus improved) and resource constraints influenced management decisions.

CONCLUSIONS

Improvements in chicken management practices could mitigate the exposure of household members to environmental contamination. Our findings highlight the need for training and resources to promote safe animal husbandry practices and optimal child health in nutrition-sensitive livestock projects.

TRIAL REGISTRATION

Clinical trials number: NCT03152227 ; Retrospectively registered at ClinicalTrials.gov on May 12, 2012.

Leveraging water, sanitation and hygiene for nutrition in low- and middle-income countries: A conceptual framework

In low‐ and middle‐income countries (LMICs), access to water, sanitation and hygiene (WASH) is associated with nutritional status including stunting, which affects 144 million children under 5 globally. Despite the consistent epidemiological association between WASH indicators and nutritional status, the provision of WASH interventions alone has not been found to improve child growth in recent randomized control trials. We conducted a literature review to develop a new conceptual framework that highlights what is known about the WASH to nutrition pathways, the limitations of certain interventions and how future WASH could be leveraged to benefit nutritional status in populations. This new conceptual framework will provide policy makers, program implementors and researchers with a visual tool to bring into perspective multiple levels of WASH and how it may effectively influence nutrition while identifying existing gaps in implementation and research.

The Lived Experiences of Community Health Workers Serving in a Large-Scale Water, Sanitation, and Hygiene Intervention Trial in Rural Bangladesh

Community health workers (CHWs) are key to implementing community-based health interventions and quality can be enhanced by better understanding their lived experiences. The WASH Benefits, Bangladesh trial engaged 540 female CHWs to promote varying health intervention packages. We report on factors influencing their lived experiences during the trial, to aid future recruitment, training and retention of CHWs. Nine focus groups and 18 in-depth interviews were conducted with CHWs. Focus groups and interviews were transcribed and thematic content analysis performed to summarize the results. All CHWs described experiencing positive working conditions and many benefits both socially and financially; these contributed to their retention and job satisfaction. Their honorarium was commonly applied towards their children's education and invested for income generation. CHWs gained self-confidence as women, to move unaccompanied in the community and speak in public. They earned respect from the community and their family members who helped them manage their family obligations during work and were viewed as a resource for advice on health and social issues. Many participated in family decision-making from which they were previously excluded. Health programs should foster a positive experience among their CHWs to aid the recruitment, retention and development of this important human resource.

Formative research for the development of baby water, sanitation, and hygiene interventions for young children in the Democratic Republic of the Congo (REDUCE program)

BACKGROUND

Research exploring the unique exposure pathways to fecal pathogens for young children and innovative water, sanitation, and hygiene (WASH) interventions for susceptible pediatric populations is needed to reduce the burden of diarrheal diseases and stunting globally. The Reducing Enteropathy, Diarrhea, Undernutrition, and Contamination in the Environment (REDUCE) program seeks to 1) identify exposure pathways to fecal pathogens that are significant contributors to morbidity for young children in South Kivu, Democratic Republic of the Congo, and 2) develop and evaluate scalable interventions that reduce fecal contamination and exposure from these pathways. The formative research portion of the project sought to identify feasible and acceptable WASH interventions to modify behaviors found to be associated with diarrheal disease and impaired growth in our REDUCE cohort study.

METHODS

Ninety-one semi-structured interviews, 6 focus group discussions, and a pilot study of 102 households were conducted during 24 months of formative research. Thirty-one interviews and six focus group discussions were conducted with caregivers, community health workers, and village leaders to explore existing WASH practices and to identify barriers and facilitators to WASH behaviors. Findings were organized using the Integrated Behavioral Model for Water, Sanitation and Hygiene to facilitate interpretation and identify determinants to Baby WASH behaviors in this setting. Care Group modules and enabling technology were developed based on exploratory findings and then revised during a two-part, iterative pilot study. Sixty interviews were conducted with participants in a pilot study of the REDUCE Baby WASH Care Group modules to learn about their experiences with the intervention.

RESULTS

Six REDUCE Baby WASH Care Group modules were developed based on formative research findings and covered the following topics: 1) living with animals; 2) child mouthing of fomites and feces; 3) composting animal feces; 4) child feces disposal; 5) handwashing with soap; and 6) water treatment.

CONCLUSION

This study took a theory-driven and evidence-based approach to formative research and the development of the REDUCE Baby WASH Care Group modules. Intervention design focused on interrupting the exposure routes for infants and young children to fecal pathogens in the environment and promoting low-cost, low-burden Baby WASH behavioral recommendations and enabling technology. These developed REDUCE Baby WASH Care Group modules are currently being rolled out to over 1,000,000 beneficiaries in Democratic Republic of the Congo.

Achieving equitable uptake of handwashing and sanitation by addressing both supply and demand-based constraints: findings from a randomized controlled trial in rural Bangladesh

Background

Supply driven programs that are not closely connected to community demand and demand-driven programs that fail to ensure supply both risk worsening inequity. Understanding patterns of uptake of behaviors among the poorest under ideal experimental conditions, such as those of an efficacy trial, can help identify strategies that could be strengthened in routine programmatic conditions for more equitable uptake. WASH Benefits Bangladesh was a randomized controlled efficacy trial that provided free-of cost WASH hardware along with behavior change promotion. The current paper aimed to determine the impact of the removal of supply and demand constraints on the uptake of handwashing and sanitation behaviors across wealth and education levels.

Methods

The current analysis selected 4 indicators from the WASH Benefits trial— presence of water and soap in household handwashing stations, observed mother’s hand cleanliness, observed visible feces on latrine slab or floor and reported last child defecation in potty or toilet. A baseline assessment was conducted immediately after enrolment and endline assessment was conducted approximately 2 years later. We compared change in uptake of these indicators including wealth quintiles (Q) between intervention and control groups from baseline to endline.

Results

For hand cleanliness, the poorest mothers improved more [Q1 difference in difference, DID: 16% (7, 25%)] than the wealthiest mothers [Q5 DID: 7% (− 4, 17%)]. The poorest households had largest improvements for observed presence of water and soap in handwashing station [Q1 DID: 82% (75, 90%)] compared to the wealthiest households [Q5 DID: 39% (30, 50%)]. Similarly, poorer household demonstrated greater reductions in visible feces on latrine slab or floor [Q1DID, − 25% (− 35, − 15) Q2: − 34% (− 44, − 23%)] than the wealthiest household [Q5 DID: − 1% (− 11, 8%). For reported last child defecation in potty or toilet, the poorest mothers showed greater improvement [Q1–4 DID: 50–54% (44, 60%)] than the wealthier mothers [Q5 DID: 39% (31, 46%).

Conclusion

By simultaneously addressing supply and demand-constraints among the poorest, we observed substantial overall improvements in equity. Within scaled-up programs, a separate targeted strategy that relaxes constraints for the poorest can improve the equity of a program.

Trial registration

WASH Benefits Bangladesh: ClinicalTrials.gov, identifier: NCT01590095. Date of registration: April 30, 2012 ‘Retrospectively registered’.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12939-020-01353-7.

Effects of Water, Sanitation, Handwashing, and Nutritional Interventions on Environmental Enteric Dysfunction in Young Children: A Cluster-randomized, Controlled Trial in Rural Bangladesh

BACKGROUND

We hypothesized that drinking water, sanitation, handwashing (WSH), and nutritional interventions would improve environmental enteric dysfunction (EED), a potential contributor to stunting.

METHODS

Within a subsample of a cluster-randomized, controlled trial in rural Bangladesh, we enrolled pregnant women in 4 arms: control, WSH, child nutrition counseling plus lipid-based nutrient supplements (N), and nutrition plus WSH (N+WSH). Among the birth cohort, we measured biomarkers of gut inflammation (myeloperoxidase, neopterin), permeability (alpha-1-antitrypsin, lactulose, mannitol), and repair (regenerating gene 1β) at median ages 3, 14, and 28 months. Analysis was intention-to-treat.

RESULTS

We assessed 1512 children. At age 3 months, compared to controls, neopterin was reduced by nutrition (-0.21 log nmol/L; 95% confidence interval [CI], -.37, -.05) and N+WSH (-0.20 log nmol/L; 95% CI, -.34, -.06) interventions; similar reductions were observed at 14 months. At 3 months, all interventions reduced lactulose and mannitol (-0.60 to -0.69 log mmol/L). At 28 months, myeloperoxidase was elevated in the WSH and nutrition arms (0.23-0.27 log ng/mL) and lactulose was higher in the WSH arm (0.30 log mmol/L; 95% CI, .07, .53).

CONCLUSIONS

Reductions in permeability and inflammation at ages 3 and 14 months suggest that the interventions promoted healthy intestinal maturation; however, by 28 months, the WSH and nutrition arms showed elevated EED biomarkers. These results underscore the importance of developing a better understanding of EED pathophysiology and targeting interventions early in childhood, when they are likely to have the largest benefit to intestinal health.

CLINICAL TRIALS REGISTRATION

NCT01590095.

Hand-washing promotion for preventing diarrhoea

BACKGROUND

Diarrhoea accounts for 1.8 million deaths in children in low- and middle-income countries (LMICs). One of the identified strategies to prevent diarrhoea is hand washing.

OBJECTIVES

To assess the effects of hand-washing promotion interventions on diarrhoeal episodes in children and adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, nine other databases, the World Health Organization (WHO) International Clinical Trial Registry Platform (ICTRP), and metaRegister of Controlled Trials (mRCT) on 8 January 2020, together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

Individually-randomized controlled trials (RCTs) and cluster-RCTs that compared the effects of hand-washing interventions on diarrhoea episodes in children and adults with no intervention.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trial eligibility, extracted data, and assessed risks of bias. We stratified the analyses for child day-care centres or schools, community, and hospital-based settings. Where appropriate, we pooled incidence rate ratios (IRRs) using the generic inverse variance method and a random-effects model with a 95% confidence interval (CI). We used the GRADE approach to assess the certainty of the evidence.

MAIN RESULTS

We included 29 RCTs: 13 trials from child day-care centres or schools in mainly high-income countries (54,471 participants), 15 community-based trials in LMICs (29,347 participants), and one hospital-based trial among people with AIDS in a high-income country (148 participants). All the trials and follow-up assessments were of short-term duration. Hand-washing promotion (education activities, sometimes with provision of soap) at child day-care facilities or schools prevent around one-third of diarrhoea episodes in high-income countries (incidence rate ratio (IRR) 0.70, 95% CI 0.58 to 0.85; 9 trials, 4664 participants, high-certainty evidence) and may prevent a similar proportion in LMICs, but only two trials from urban Egypt and Kenya have evaluated this (IRR 0.66, 95% CI 0.43 to 0.99; 2 trials, 45,380 participants; low-certainty evidence). Only four trials reported measures of behaviour change, and the methods of data collection were susceptible to bias. In one trial from the USA hand-washing behaviour was reported to improve; and in the trial from Kenya that provided free soap, hand washing did not increase, but soap use did (data not pooled; 3 trials, 1845 participants; low-certainty evidence). Hand-washing promotion among communities in LMICs probably prevents around one-quarter of diarrhoea episodes (IRR 0.71, 95% CI 0.62 to 0.81; 9 trials, 15,950 participants; moderate-certainty evidence). However, six of these nine trials were from Asian settings, with only one trial from South America and two trials from sub-Saharan Africa. In seven trials, soap was provided free alongside hand-washing education, and the overall average effect size was larger than in the two trials which did not provide soap (soap provided: RR 0.66, 95% CI 0.58 to 0.75; 7 trials, 12,646 participants; education only: RR 0.84, 95% CI 0.67 to 1.05; 2 trials, 3304 participants). There was increased hand washing at major prompts (before eating or cooking, after visiting the toilet, or cleaning the baby's bottom) and increased compliance with hand-hygiene procedure (behavioural outcome) in the intervention groups compared with the control in community trials (data not pooled: 4 trials, 3591 participants; high-certainty evidence). Hand-washing promotion for the one trial conducted in a hospital among a high-risk population showed significant reduction in mean episodes of diarrhoea (1.68 fewer) in the intervention group (mean difference -1.68, 95% CI -1.93 to -1.43; 1 trial, 148 participants; moderate-certainty evidence). Hand-washing frequency increased to seven times a day in the intervention group versus three times a day in the control arm in this hospital trial (1 trial, 148 participants; moderate-certainty evidence). We found no trials evaluating the effects of hand-washing promotions on diarrhoea-related deaths or cost effectiveness.

AUTHORS' CONCLUSIONS

Hand-washing promotion probably reduces diarrhoea episodes in both child day-care centres in high-income countries and among communities living in LMICs by about 30%. The included trials do not provide evidence about the long-term impact of the interventions.

Food Safety Considerations Related to the Consumption and Handling of Game Meat in North America

Emerging foodborne pathogens present a threat to public health. It is now recognized that several foodborne pathogens originate from wildlife as demonstrated by recent global disease outbreaks. Zoonotic spillover events are closely related to the ubiquity of parasitic, bacterial, and viral pathogens present within human and animal populations and their surrounding environment. Foodborne diseases have economic and international trade impacts, incentivizing effective wildlife disease management. In North America, there are no food safety standards for handling and consumption of free-ranging game meat. Game meat consumption continues to rise in North America; however, this growing practice could place recreational hunters and game meat consumers at increased risk of foodborne diseases. Recreational hunters should follow effective game meat food hygiene practices from harvest to storage and consumption. Here, we provide a synthesis review that evaluates the ecological and epidemiological drivers of foodborne disease risk in North American hunter populations that are associated with the harvest and consumption of terrestrial mammal game meat. We anticipate this work could serve as a foundation of preventive measures that mitigate foodborne disease transmission between free-ranging mammalian and human populations.

Measuring Environmental Exposure to Enteric Pathogens in Low-Income Settings: Review and Recommendations of an Interdisciplinary Working Group

Infections with enteric pathogens impose a heavy disease burden, especially among young children in low-income countries. Recent findings from randomized controlled trials of water, sanitation, and hygiene interventions have raised questions about current methods for assessing environmental exposure to enteric pathogens. Approaches for estimating sources and doses of exposure suffer from a number of shortcomings, including reliance on imperfect indicators of fecal contamination instead of actual pathogens and estimating exposure indirectly from imprecise measurements of pathogens in the environment and human interaction therewith. These shortcomings limit the potential for effective surveillance of exposures, identification of important sources and modes of transmission, and evaluation of the effectiveness of interventions. In this review, we summarize current and emerging approaches used to characterize enteric pathogen hazards in different environmental media as well as human interaction with those media (external measures of exposure), and review methods that measure human infection with enteric pathogens as a proxy for past exposure (internal measures of exposure). We draw from lessons learned in other areas of environmental health to highlight how external and internal measures of exposure can be used to more comprehensively assess exposure. We conclude by recommending strategies for advancing enteric pathogen exposure assessments.

Dietary consumption and its effect on nutrition outcome among under-five children in rural Malawi

BACKGROUND

Despite remarkable progress in reducing under five mortalities in Malawi, a relative proportion of under nutrition among children still exist.

OBJECTIVES

The study examines dietary consumption factors and their effect on under nutrition outcomes among children under five years' children in rural Malawi.

METHODS

Using the 2015-16 Malawi Demographic and Health Survey, in which 4,150 children were reported of under nutrition statuses, the study used nested logistic regression models to estimate factors influencing the prevalence of under nutrition among children.

RESULTS

Based on the results, exclusive breast feeding among children under five years, after controlling for parental socioeconomic factors, was found to reduce the levels of wasting (ODDS RATIO [OR] = 0.763; p < 0.05), underweight (OR = 0.548; p < 0.001) and stunting (OR = 0.709; p < 0.005). Furthermore, it was found that despite the perceived adequacy among women in accessing fruits and vegetables, carbohydrates and micro-nutrient supplements, their children under five years, still experiences public health challenges and suffers from wasting, underweight and stunting.

CONCLUSION

There is need to implement extensive pro-rural under five nutritional and health educational advocacy using community-based approaches, targeting parents, emphasizing the significance of exclusive breast feeding and consistencies in giving dietary foods, if and only if the persistent public health challenges due to under nutrition among children under five years, is to be sustainably dealt with, in Malawi.

Exposure to open defecation can account for the Indian enigma of child height

Physical height is an important measure of human capital. However, differences in average height across developing countries are poorly explained by economic differences. Children in India are shorter than poorer children in Africa, a widely studied puzzle called "the Asian enigma." This paper proposes and quantitatively investigates the hypothesis that differences in sanitation - and especially in the population density of open defecation - can statistically account for an important component of the Asian enigma, India's gap relative to sub-Saharan Africa. The paper's main result computes a demographic projection of the increase in the average height of Indian children, if they were counterfactually exposed to sub-Saharan African sanitation, using a non-parametric reweighting method. India's projected increase in mean height is at least as large as the gap. The analysis also critically reviews evidence from recent estimates in the literature. Two possible mechanisms are effects on children and on their mothers.

Effect of water, sanitation, handwashing and nutrition interventions on enteropathogens in children 14 months old: a cluster-randomized controlled trial in rural Bangladesh

BACKGROUND

We evaluated the impact of low-cost water, sanitation, handwashing (WSH) and child nutrition interventions on enteropathogen carriage in the WASH Benefits cluster-randomized controlled trial in rural Bangladesh.

METHODS

We analyzed 1411 routine fecal samples from children 14±2 months old in the WSH (n = 369), nutrition counseling plus lipid-based nutrient supplement (n = 353), nutrition plus WSH (n = 360), and control (n = 329) arms for 34 enteropathogens using quantitative PCR. Outcomes included the number of co-occurring pathogens; cumulative quantity of four stunting-associated pathogens; and prevalence and quantity of individual pathogens. Masked analysis was by intention-to-treat.

RESULTS

326 (99.1%) control children had one or more enteropathogens detected (mean 3.8±1.8). Children receiving WSH interventions had lower prevalence and quantity of individual viruses than controls (prevalence difference for norovirus: -11% [95% confidence interval [CI], -5 to -17%]; sapovirus: -9% [95%CI, -3 to -15%]; and adenovirus 40/41: -9% [95%CI, -2 to - 15%]). There was no difference in bacteria, parasites, or cumulative quantity of stunting-associated pathogens between controls and any intervention arm.

CONCLUSIONS

WSH interventions were associated with fewer enteric viruses in children aged 14 months. Different strategies are needed to reduce enteric bacteria and parasites at this critical young age.

Child defecation and feces management practices in rural Bangladesh: Associations with fecal contamination, observed hand cleanliness and child diarrhea

Child open defecation is common in low-income countries and can lead to fecal exposure in the domestic environment. We assessed associations between child feces management practices vs. measures of contamination and child diarrhea among households with children <5 years in rural Bangladesh. We visited 360 households quarterly and recorded caregiver-reported diarrhea prevalence, and defecation and feces disposal practices for children <5 years. We examined caregiver and child hands for visible dirt and enumerated E. coli in child and caregiver hand rinse and stored drinking water samples. Safe child defecation (in latrine/potty) and safe feces disposal (in latrine) was reported by 21% and 23% of households, respectively. Controlling for potential confounders, households reporting unsafe child defecation had higher E. coli prevalence on child hands (prevalence ratio [PR] = 1.12, 1.04-1.20) and in stored water (PR = 1.12,1.03-1.21). Similarly, households reporting unsafe feces disposal had higher E. coli prevalence on child hands (PR = 1.11, 1.02-1.21) and in stored water (PR = 1.10, 1.03-1.18). Effects on E. coli levels were similar. Children in households with unsafe defecation and feces disposal had higher diarrhea prevalence but the associations were not statistically significant. Our findings suggest that unsafe child feces management may present a source of fecal exposure for young children.

High-Throughput Multiparallel Enteropathogen Detection via Nano-Liter qPCR

Quantitative molecular diagnostic methods can effectively detect pathogen-specific nucleic acid sequences, but costs associated with multi-pathogen panels hinder their widespread use in research trials. Nano-liter qPCR (nL-qPCR) is a miniaturized tool for quantification of multiple targets in large numbers of samples based on assay parallelization on a single chip, with potentially significant cost-savings due to rapid throughput and reduced reagent volumes. We evaluated a suite of novel and published assays to detect 17 enteric pathogens using a commercially available nL-qPCR technology. Amplification efficiencies ranged from 88 to 98% (mean 91%) and were reproducible across four operators at two separate facilities. When applied to fecal material, assays were sensitive and selective (99.8% of DNA amplified were genes from the target organism). Due to nanofluidic volumes, detection limits were 1-2 orders of magnitude less sensitive for nL-qPCR than an enteric TaqMan Array Card (TAC). However, higher detection limits do not hinder detection of diarrhea-causing pathogen concentrations. Compared to TAC, nL-qPCR displayed 99% (95% CI 0.98, 0.99) negative percent agreement and 62% (95% CI 0.59, 0.65) overall positive percent agreement for presence of pathogens across diarrheal and non-diarrheal fecal samples. Positive percent agreement was 89% among samples with concentrations above the nL-qPCR detection limits. nL-qPCR assays showed an underestimation bias of 0.34 log₁₀ copies/gram of stool [IQR -0.40, -0.28] compared with TAC. With 12 times higher throughput for a sixth of the per-sample cost of the enteric TAC, the nL-qPCR chip is a viable alternative for enteropathogen quantification for studies where other technologies are cost-prohibitive.

Effect of water, sanitation and hygiene interventions alone and combined with nutrition on child growth in low and middle income countries: a systematic review and meta-analysis

OBJECTIVE

This study aimed to provide clarification on the benefits of water, sanitation and hygiene (WASH) alone separately and combined with nutrition in improving child growth outcomes.

DESIGN

Systematic review and meta-analysis.

METHODS

We conducted a systematic review using the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. PubMed, MEDLINE, EMBASE, Scopus, Cochrane Library, Web of Science and Science Direct were searched in May 2018 and last updated in April 2019. We included studies that reported WASH interventions alone separately or combined with nutrition. Fixed and random-effects models were used to estimate pooled effect in mean difference (MD). Heterogeneity and publication bias statistics were performed.

RESULTS

A total of 18 studies were included: 13 cluster randomised controlled trials (RCTs) and 5 non-randomised controlled trials (non-RCTs). Non-RCTs showed effect of WASH interventions alone on height-for-age z-score (HAZ) (MD=0.14; 95% CI 0.08 to 0.21) but RCTs did not. WASH alone of non-RCTs and RCTs that were delivered over 18-60 months indicated an effect on HAZ (MD=0.04; 95% CI 0.01 to 0.08). RCTs showed an effect for children <2 years (MD=0.07; 95% CI 0.01 to 0.13). Non-RCTs of WASH alone and those that included at least two components, improved HAZ (MD=0.15; 95% CI 0.07 to 0.23) but RCTs did not. WASH alone of non-RCTs and RCTs separately or together showed no effect on weight-for-age z-score (WAZ) and weight-for-height z-score (WHZ). Combined WASH with nutrition showed an effect on HAZ (MD=0.13; 95% CI 0.08 to 0.17) and on WAZ (MD=0.09; 95% CI 0.05 to 0.13) and was borderline on WHZ.

CONCLUSIONS

WASH interventions alone improved HAZ when delivered over 18-60 months and for children <2 years. Combined WASH with nutrition showed a strong effect on HAZ and WAZ and a borderline effect on WHZ. Integrated WASH with nutrition interventions may be effective inimproving child growth outcomes.

Effect of Improved Water Quality, Sanitation, Hygiene and Nutrition Interventions on Respiratory Illness in Young Children in Rural Bangladesh: A Multi-Arm Cluster-Randomized Controlled Trial

Acute respiratory infections cause mortality in young children. We assessed the effects of water, sanitation, hygiene (WASH) and nutritional interventions on childhood ARI. Geographic clusters of pregnant women from rural Bangladesh were randomly assigned to receive 1) chlorinated drinking water and safe storage (W); 2) upgraded sanitation (S); 3) handwashing promotion (H); 4) combined water, sanitation, and handwashing (WSH); 5) nutrition intervention including lipid-based nutrient supplements; 6) combined WSH plus nutrition (WSHN); or 7) no intervention (control). Masking of participants was not possible. Acute respiratory illness was defined as caregiver-reported persistent cough, panting, wheezing, or difficulty breathing in the past 7 days among index children, those born to enrolled women. We assessed outcomes at 12 and 24 months of intervention using intention to treat. Compared with children in the control group (ARI prevalence, P: 8.9%), caregivers of index children reported significantly lower ARI in the water (P: 6.3%, prevalence ratio (PR): 0.71; 95% CI: 0.53, 0.96), sanitation (P: 6.4%, PR: 0.75, 95% CI: 0.58, 0.96), handwashing (P: 6.4%, PR: 0.68, 95% CI: 0.50, 0.93), and the combined WSH+N arms (P: 5.9%, PR: 0.67, 95% CI: 0.50, 0.90). Those in the nutrition (P: 7.4%, PR: 0.84, 95% CI: 0.63, 1.10) or the WSH arm (P: 8.9%, PR: 0.99, 95% CI: 0.76, 1.28) reported similar ARI prevalence compared with control children. Single targeted water, sanitation, and hygiene interventions reduced reported respiratory illness in young children. There was no apparent respiratory health benefit from combining WASH interventions.

JM, Mertens A, Hubbard AE, Arnold BF. Internal replication of computational workflows in scientific research

Failures to reproduce research findings across scientific disciplines from psychology to physics have garnered increasing attention in recent years. External replication of published findings by outside investigators has emerged as a method to detect errors and bias in the published literature. However, some studies influence policy and practice before external replication efforts can confirm or challenge the original contributions. Uncovering and resolving errors before publication would increase the efficiency of the scientific process by increasing the accuracy of published evidence. Here we summarize the rationale and best practices for internal replication, a process in which multiple independent data analysts replicate an analysis and correct errors prior to publication. We explain how internal replication should reduce errors and bias that arise during data analyses and argue that it will be most effective when coupled with pre-specified hypotheses and analysis plans and performed with data analysts masked to experimental group assignments. By improving the reproducibility of published evidence, internal replication should contribute to more rapid scientific advances.

Comparison of multi-parallel qPCR and double-slide Kato-Katz for detection of soil-transmitted helminth infection among children in rural Bangladesh

There is growing interest in local elimination of soil-transmitted helminth (STH) infection in endemic settings. In such settings, highly sensitive diagnostics are needed to detect STH infection. We compared double-slide Kato-Katz, the most commonly used copromicroscopic detection method, to multi-parallel quantitative polymerase chain reaction (qPCR) in 2,799 stool samples from children aged 2–12 years in a setting in rural Bangladesh with predominantly low STH infection intensity. We estimated the sensitivity and specificity of each diagnostic using Bayesian latent class analysis. Compared to double-slide Kato-Katz, STH prevalence using qPCR was almost 3-fold higher for hookworm species and nearly 2-fold higher for Trichuris trichiura. Ascaris lumbricoides prevalence was lower using qPCR, and 26% of samples classified as A. lumbricoides positive by Kato-Katz were negative by qPCR. Amplicon sequencing of the 18S rDNA from 10 samples confirmed that A. lumbricoides was absent in samples classified as positive by Kato-Katz and negative by qPCR. The sensitivity of Kato-Katz was 49% for A. lumbricoides, 32% for hookworm, and 52% for T. trichiura; the sensitivity of qPCR was 79% for A. lumbricoides, 93% for hookworm, and 90% for T. trichiura. Specificity was ≥ 97% for both tests for all STH except for Kato-Katz for A. lumbricoides (specificity = 68%). There were moderate negative, monotonic correlations between qPCR cycle quantification values and eggs per gram quantified by Kato-Katz. While it is widely assumed that double-slide Kato-Katz has few false positives, our results indicate otherwise and highlight inherent limitations of the Kato-Katz technique. qPCR had higher sensitivity than Kato-Katz in this low intensity infection setting.

Soil-transmitted helminth infections (STH) (e.g., Ascaris, hookworm, Trichuris) contribute to a large burden of disease among children in low- and middle-income countries. There is increasing interest in implementing large-scale deworming programs to eliminate STH in certain settings. Efforts to monitor whether local elimination has occurred require sensitive diagnostic tests that will not miss positive cases. Kato-Katz, a microscopy-based diagnostic test, has commonly been used to identify STH eggs in stool, but in settings where infection intensity is low, this method frequently misses positive samples because it requires visual identification of small numbers of eggs, and hookworm eggs may degrade prior to visualization. Quantitative polymerase chain reaction (qPCR) is a molecular diagnostic method for detecting STH. It may detect more low intensity infections than Kato-Katz because it identifies STH DNA in stool; DNA can be detected in very small quantities and is less likely to degrade than STH ova. Thus, qPCR is likely to be more accurate than Kato-Katz. This study compared the performance of double-slide Kato-Katz and qPCR using 2,799 stool samples from children aged 2–12 years in a setting in rural Bangladesh with predominantly low STH infection intensity. qPCR was more sensitive than Kato-Katz for hookworm and Trichuris infections. 26% of samples were classified as Ascaris positive by Kato-Katz and negative by qPCR. DNA sequencing of 10 samples confirmed that Ascaris was absent in samples classified as positive by Kato-Katz and negative by qPCR. We conclude that Kato-Katz likely produced false positive results for Ascaris and that qPCR had a higher sensitivity than double-slide Kato-Katz in this low infection intensity setting.

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

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

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

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

Impact of Water Quality, Sanitation, Handwashing, and Nutritional Interventions on Enteric Infections in Rural Zimbabwe: The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) Trial

BACKGROUND

We assessed the impact of water, sanitation, and hygiene (WASH) and infant and young child feeding (IYCF) interventions on enteric infections in the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in rural Zimbabwe.

METHODS

We tested stool samples collected at 1, 3, 6, and 12 months of age and during diarrhea using quantitative molecular diagnostics for 29 pathogens. We estimated the effects of the WASH, IYCF, and combined WASH + IYCF interventions on individual enteropathogen prevalence and quantity, total numbers of pathogens detected, and incidence of pathogen-attributable diarrhea.

RESULTS

WASH interventions decreased the number of parasites detected (difference in number compared to non-WASH arms, -0.07 [95% confidence interval, -.14 to -.02]), but had no statistically significant effects on bacteria, viruses, or the prevalence and quantity of individual enteropathogens after accounting for multiple comparisons. IYCF interventions had no significant effects on individual or total enteropathogens. Neither intervention had significant effects on pathogen-attributable diarrhea.

CONCLUSIONS

The WASH interventions implemented in SHINE (improved pit latrine, hand-washing stations, liquid soap, point-of-use water chlorination, and clean play space) did not prevent enteric infections. Transformative WASH interventions are needed that are more efficacious in interrupting fecal-oral microbial transmission in children living in highly contaminated environments.

Snack food consumption among Bangladeshi children, supplementary data from a large RCT

Childhood obesity has been associated with consumption of energy-dense foods such as caloric beverages and fast foods. Many low- and middle-income countries like Bangladesh are now experiencing a rising problem of noncommunicable diseases along with the long-standing problem of stunting and undernutrition. WASH Benefits Bangladesh was a large community-based cluster randomized controlled trial conducted in rural Bangladesh. Study clusters were randomized into seven arms: single nutrition (N); water (W); sanitation (S); hygiene (H); combined water, sanitation, and hygiene (WSH); WSH and nutrition (N + WSH); and a double sized control (C). Nutrition intervention messages included four promotional components: maternal nutrition, breastfeeding, complementary feeding, and lipid-based nutrient supplements. The World Health Organization infant food frequency questionnaire (24-hr recall and 7-day recall) was administered at Year 1 and Year 2 of intervention. The likelihood of any snack food consumption was significantly lower (odds ratio 0.37: 95% confidence interval [0.28, 0.49]) in the nutrition intervention arms compared to the control arm in Year 2 follow-up. In addition, in the water intervention arm, fewer children (about 50% less) consumed soft drinks, but not the other sugar-sweetened beverages, compared with control in Year 2. There were no other differences between groups. Simple messages about balanced diet and feeding family foods were effective in lowering commercially produced snack food consumption of the young children in low-income rural communities of Bangladesh. Provision of safe water apparently encouraged mothers to reduce offering unhealthy beverages to the young children.

Environmental enteric dysfunction and child stunting

In 2017, an estimated 1 in every 4 (23%) children aged < 5 years were stunted worldwide. With slow progress in stunting reduction in many regions and the realization that a large proportion of stunting is not due to insufficient diet or diarrhea alone, it remains that other factors must explain continued growth faltering. Environmental enteric dysfunction (EED), a subclinical state of intestinal inflammation, can occur in infants across the developing world and is proposed as an immediate causal factor connecting poor sanitation and stunting. A result of chronic pathogen exposure, EED presents multiple causal pathways, and as such the scope and sensitivity of traditional water, sanitation, and hygiene (WASH) interventions have possibly been unsubstantial. Although the definite pathogenesis of EED and the mechanism by which stunting occurs are yet to be defined, this paper reviews the existing literature surrounding the proposed pathology and transmission of EED in infants and considerations for nutrition and WASH interventions to improve linear growth worldwide.

JM, Mertens A, Hubbard AE, Arnold BF. Internal replication of computational workflows in scientific research

Failures to reproduce research findings across scientific disciplines from psychology to physics have garnered increasing attention in recent years. External replication of published findings by outside investigators has emerged as a method to detect errors and bias in the published literature. However, some studies influence policy and practice before external replication efforts can confirm or challenge the original contributions. Uncovering and resolving errors before publication would increase the efficiency of the scientific process by increasing the accuracy of published evidence. Here we summarize the rationale and best practices for internal replication, a process in which multiple independent data analysts replicate an analysis and correct errors prior to publication. We explain how internal replication should reduce errors and bias that arise during data analyses and argue that it will be most effective when coupled with pre-specified hypotheses and analysis plans and performed with data analysts masked to experimental group assignments. By improving the reproducibility of published evidence, internal replication should contribute to more rapid scientific advances.