PLOS Water

BackgroundThere is increasing evidence of the efficacy of point-of-use water filters on diarrhea prevalence in numerous global settings, in both observational studies and randomized experiments. Most studies, however, are focused on rural locations. Methods We use self-report household surveys to monitor a set of approximately 10,000 households receiving point-of-use water filters and WASH training in Kibera, Kenya. Twenty-five drinking water sources throughout the 7 neighborhoods were also selected for testing of E. coli, total coliform, bacterial 16S rRNA community sequencing and metals. Albendazole was provided to all households at distribution as part of the standard filter distribution protocol, with a subset of 2,642 households not receiving Albendazole at distribution, instead receiving it at the second follow-up (approximately 5 weeks after filter distribution). ResultsAfter data cleaning, a sample of 6,795 households were analyzed using mixed effects generalized linear models to account for repeated household measurements, geospatial and temporal effects, interviewer and other household covariates. Models predicted self-reported, 2-week prevalence of diarrhea. After accounting for confounding factors, self-reported diarrhea rates dropped from 52.7% to 2.2% after approximately 70 days of filter use. Field testing characterized most water sources (18 out of 25) as unsafe for Total coliforms, many for E. coli (6 out of 25), and one source above WHO health guidelines for arsenic. There was no evidence of a difference in self-reported diarrhea prevalence between households receiving Albendazole at distribution vs. those that didnt (p>0.05). ConclusionsThe introduction of Sawyer filters to households in a densely populated informal settlement reduced diarrhea and other health related problems. Representative water quality testing indicates a high frequency of drinking water source contamination with E. coli and Total Coliforms but a very low frequency of dissolved metals present, above WHO guidelines for drinking water. Anti-parasitic medication distribution had little to no impact on the results. Future randomized controlled studies with objective health measures are needed to ensure cause-effect impact of the filters, and study of filter longevity in the field continues to be a critical need.

Communities relying on drinking-water storage routinely document containers as a reservoir for pathogens when they are not properly cleaned. Although lab-based research provides guidance on cleaning protocols, gaps remain in understanding: 1) what methods are practiced, and 2) method effectiveness at reducing biofilm growth. In partnership with AFMAC, this pilot explored biofilm contamination in household water storage containers of four Zambian communities engaged in WASH-promoting community health clubs and health promoters. A mixed-methods design was used: 15-20 households per community completed a knowledge, attitudes, and practices survey and provided whole-container biofilm samples. Four focus group discussions with program members and four interviews with AFMAC staff explored container cleaning sensitizations. Findings revealed household awareness of container cleaning, inconsistent cleaning practices, and high levels of biofilm in 100% of storage containers. The absence of a standardized container cleaning module, reliance on visual cues as a proxy for microbial safety, and disproportionate burden placed on women underscore critical gaps in current programming and highlight container cleaning as a critical pathway to interrupt recontamination. This pilot highlights the need for locally adapted, practical protocols using accessible materials. Advancing container hygiene through integrated, adaptive, and scalable approaches is essential for reducing public health risks from unsafe water storage and improving point-of-use water quality. SynopsisField evidence on household water storage container cleaning is limited. The study found high biofilm levels and inconsistent cleaning of household water storage containers, revealing a gap between knowledge and practice in maintaining safe water quality. Table of Content Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/25339087v1_ufig1.gif" ALT="Figure 1000"> View larger version (49K): org.highwire.dtl.DTLVardef@1ccb1ddorg.highwire.dtl.DTLVardef@1b15447org.highwire.dtl.DTLVardef@11416b3org.highwire.dtl.DTLVardef@1de5f0b_HPS_FORMAT_FIGEXP M_FIG C_FIG

BackgroundAchieving universal access to safe and affordable drinking water remains a critical global challenge, particularly in low- and middle-income countries where intermittencies in water supply are common. We aimed to examine relationships between water intermittency and multiple outcomes, including microbial water contamination, child health, and caregiver stress. MethodsWe conducted a cross-sectional study with 237 households with a child <5 years old in a peri-urban neighborhood of Blantyre, Malawi. We conducted a structured questionnaire with primary caregivers to record water intermittencies, water handling and hygiene practices, caregiver-reported child diarrhea and acute respiratory infection (ARI) symptoms, and stress among caregivers. Drinking water samples were tested for E. coli and cefotaxime-resistant E. coli using IDEXX Quanti-Tray/2000. We used generalized linear models to evaluate how intermittency occurrence, frequency, and duration influenced outcomes, adjusting for sociodemographic and WASH factors. FindingsOf 237 households, 32.5% reported [&ge;]1 water intermittency in the past month. These households were more likely to experience water insecurity, skip bathing and laundry, and report less handwashing after animal contact or outdoor work. E. coli was detected in 65.7% and cefotaxime-resistant E. coli in 8.4% of water samples. Intermittency was not associated with impaired water quality. Children in intermittent households had higher prevalence of diarrhea (PR=1.94, 95% CI: 1.11-3.39) and ARI with fever (PR=2.00, 95% CI: 1.11-3.60). Rare/short intermittencies were more strongly associated with diarrhea; frequent/long intermittencies were more strongly associated with ARI. Caregivers in households with short and frequent intermittencies reported higher stress. InterpretationWater intermittencies were associated with impaired hygiene, child illness, and caregiver stress. Frequency and duration modified the associations, suggesting that short- vs. long-term behavioral adaptations may differently influence exposure to enteric and respiratory pathogens and stress responses. Interventions like low-flow handwashing stations and water reuse may help reduce health risks in intermittent water settings.

In-line chlorination automatically treats drinking water in piped water systems or at points-of-collection, substantially reducing morbidity and mortality while averting the burden of water treatment on individuals. Approximately 2.3 billion people globally use fecally contaminated drinking water infrastructure that is potentially compatible with in-line chlorination. In India, the Ministry of Jal Shaktis Jal Jeevan Mission has increased access to piped drinking water among rural households, however, water is often supplied intermittently without treatment. The aims of this study were to 1) test installation and operational procedures for in-line chlorination in rural drinking water systems, 2) evaluate acceptability and adoption of chlorinated water, and 3) assess reductions in drinking water fecal contamination, including with antibiotic resistant bacteria. We conducted a randomized controlled implementation trial of in-line chlorination in 20 villages in Rayagada district, Odisha, India over a 1-year period. Data collection included a baseline and post-intervention census (N=914) and surveys with a random subset of households over six timepoints (N=1,041) to assess water quality. We discuss operational challenges, including maintaining consistent chlorine dosing and addressing taste and odor preferences. In the treatment group, we detected free chlorine residual in 51% of tap water samples; this prevalence rose to 80% after increasing the target dose. Despite taste complaints in treatment communities, participants continued using piped water as their primary drinking water source. Individuals in treatment communities reported reduced time spent manually treating their drinking water, a responsibility borne by women in 92% of households. Treatment reduced E. coli prevalence by 70% in household tap water and by 47% in stored water, as well as reduced the presence of antibiotic resistant E. coli. In-line chlorination can lead to better quality water, lower the time burden of water treatment, and increase user adoption of chlorinated drinking water, but achieving this requires dedicated implementation and monitoring.

Weather events associated with climate change can influence the environmental spread and survival of fecal pathogens, potentially impacting the efficacy of water, sanitation, and hygiene (WASH) interventions. We used longitudinal data from a randomized controlled trial in Bangladesh to assess whether rainfall and temperature modified the effect of an on-site sanitation intervention on fecal contamination. Over 3.5 years, we enumerated E. coli in household samples along eight fecal-oral pathways (n=23,238 samples) and obtained daily weather data. The intervention included the provision of double-pit latrines, child potties, and scoops for removing child and animal feces, along with behavior change promotion. The intervention was associated with larger reductions in E. coli in/on mother hands, child hands, ponds, and flies (0.10-log to 0.91-log) following higher rainfall and in/on food, mother hands, child hands, soil, and ponds (0.11-log to 0.40-log) following higher temperatures, compared to drier and colder periods. The intervention slightly reduced E. coli in stored drinking water and had no consistent effect on E. coli in tubewell water, regardless of weather. Our findings suggest that sanitation interventions can help mitigate the effects of increased rainfall and temperature on environmental fecal contamination. Previous analyses of these data without stratification by daily weather only found small (approximately 0.10-log) reductions in E. coli in/on stored drinking water and child hands. Future WASH trials should incorporate weather data to identify periods of differential intervention effectiveness to understand how weather variability influences the outcomes of public health interventions and develop strategies to enhance resilience against climate change impacts in vulnerable communities. Research in ContextO_ST_ABSEvidence before this studyC_ST_ABSHigher temperatures and increased rainfall linked to climate change have been associated with increased infectious disease transmission. Effective water, sanitation, and hygiene (WASH) interventions, such as access to improved sanitation facilities, are pivotal in reducing these risks. However, the efficacy of WASH interventions in interrupting fecal-oral transmission can be influenced by weather fluctuations, which can compromise service delivery and/or exacerbate environmental dissemination of fecal waste. We conducted a literature review on the impact of weather events and climate change on the environmental spread of fecal pathogens and their influence on WASH interventions. We used Google Scholar to identify articles published from 2000 to 2024 using the following search terms: ("climate change" OR weather OR weather events OR temperature OR heatwave OR rainfall OR precipitation) AND (sanitation OR "WASH intervention" OR "sanitation intervention" OR "intervention efficacy") AND (pathogen OR enteropathogen OR "Escherichia coli" OR "E. coli" OR "fecal indicator" OR "fecal contamination" OR "fecal pathogens). Studies have documented the influence of weather conditions, particularly rainfall and temperature, on the effectiveness of WASH interventions in reducing fecal contamination and diarrhea. A recent meta-analysis found that lack of access to improved latrines and piped drinking water modified the association between rainfall/temperature and diarrhea incidence in children under the age of five but this analysis only focused on health outcomes and did not include measures of environmental contamination. In Bangladesh, WASH interventions, including water treatment and handwashing, were more effective in reducing E. coli contamination in stored drinking water and food during dry seasons compared to wet seasons, however, in a different longitudinal analysis focused on a sanitation intervention, seasonality did not significantly modify the relationship between the intervention and fecal contamination. However, these studies used seasonal definitions (wet vs. dry) which can miss transient weather fluctuations within a season. One study in Kenya used daily rainfall and temperature data to show that increases in drinking water contamination associated with increased rainfall were mitigated if households treated their water. No study has evaluated the influence of daily weather parameters on the effect of WASH improvements on a comprehensive set of fecal-oral pathways. Added value of this studyThis study utilizes longitudinal data from a randomized controlled trial that implemented water treatment, handwashing and sanitation interventions in Bangladesh (WASH Benefits), with over 23,000 E. coli measurements collected over 3.5 years. The measurements were taken along eight fecal-oral transmission pathways, including mother and child hands, stored food, stored drinking water, groundwater from tubewells, ponds, courtyard soil, and captured flies. Previous analyses of these data with no stratification by daily weather found only small reductions in environmental fecal contamination associated with the WASH interventions. In the present analysis, we re-analyzed these data using daily weather measurements to investigate whether rainfall and temperature modified the efficacy of the improved on-site sanitation intervention in reducing E. coli contamination in the domestic environment. Unlike previous analyses that did not consider daily weather variations, stratifying by daily weather conditions revealed differential intervention impacts on E. coli contamination, with larger reductions observed following periods of higher rainfall and temperature across multiple fecal-oral pathways (mother hands, child hands, food, soil, ponds, and flies). Implications of all the available evidenceUnderstanding how interventions perform under varying weather conditions is crucial, particularly in low- and middle-income countries susceptible to extreme weather events. Integrating fine-grained weather data into sanitation intervention assessments can inform climate adaptation strategies. Our findings, combined with evidence from previous studies, indicate that on-site sanitation improvements, water treatment and broader WASH approaches can help protect against environmental fecal contamination associated with increased rainfall and temperatures. These insights are pivotal for designing resilient WASH interventions capable of mitigating climate-related health risks in vulnerable populations, supporting the Sustainable Development Goals in low- and middle-income countries. The WASH Benefits sanitation interventions implemented in rural Bangladesh demonstrated enhanced efficacy during periods of higher rainfall and temperature. These effects were not discernible in previous analyses that did not stratify by daily weather, where average reductions in E. coli counts were minimal, underscoring the importance of capturing weather variability in assessing intervention impacts. This approach also contrasts with earlier studies using calendar-based definitions of seasons, which may not fully capture the nuanced effects of climate variables on intervention efficacy. Collectively, these findings underscore the importance of incorporating fine-grained weather data in WASH trials to enhance the understanding of intervention efficacy under variable environmental conditions.

BackgroundWater insecurity, a global public health crisis, will be intensified by climate change. In coastal Peru, little is known about the health effects of water insecurity from a community perspective. Understanding first-hand experiences and perceptions of mothers and healthcare providers can inform strategies to mitigate the effects of water insecurity and climate change on health outcomes and health disparities. MethodsThis qualitative study took place in 2023 in Carabayllo, the Northernmost region of Lima, Peru comprised of urban and rural communities. We conducted six focus groups with 10 pregnant women and 23 mothers of children ages 0 to 10, as well as individual interviews with 22 healthcare providers. Data were analyzed through rapid qualitative analysis combining deductive and inductive methods. Principal findingsWater insecurity was common among community members and was normalized as part of daily life. Access to water varied based on socioeconomic status and geography. Perceived health impacts were primarily related to hygiene and sanitation (e.g. diarrheal disease), water storage (dengue), and longer-term effects such as nutrition and child development. Respondents agreed that climate change would exacerbate water insecurity and endorsed strategies to take action. Conclusions and significanceThe lived experiences of water insecurity and its health impacts in Lima, Peru highlight the importance of mobilizing community stakeholders, health systems and local government to increase water security and support healthcare facilities and communities on water conservation and climate preparedness efforts.

BackgroundFrom April 25, 2014, to October 15, 2015, residents of Flint, Michigan, were unknowingly exposed to contaminated water after a drinking water source switch. This public health disaster, the Flint water crisis (FWC), resulted in population-wide lead-in-water exposure for 18 months. A potent neurotoxin, lead is associated with multiple long-term adverse health conditions. In response to the FWC, the Flint Registry (FR) was formed to mitigate the impact of the crisis by proactively identifying the health and development concerns of participants and providing secondary prevention resources to address their needs. MethodsDesigned as a public health intervention with robust community engagement in every aspect, the FR enrollment is non-end-dated with ongoing evaluation and screening. Eligibility requirements include individuals who lived, worked, or went to school at an address serviced by the City of Flint water system anytime from 4/25/2014 to 10/15/2015, including those exposed prenatally. Recruitment is list-based, community-outreach-based, and marketing-based. Participants enroll primarily online or by phone and complete a survey to evaluate health impacts of the FWC and screen for service needs. Data collected at enrollment includes demographics, physical/mental health, child development, prior utilization of services, and environmental/lead-exposure risks. Based on responses, enrollees are referred within a community referral network to services in the categories of lead elimination, health, nutrition, and child development via an automated process. Frequencies of reported diagnoses, health symptoms, food access/insecurity problems, and educational support needs are compared to city, county, state, and national measures to identify ongoing disparities. Referrals identify the unmet needs for secondary prevention services. DiscussionThe FR protocol is unique because it not only conducts longitudinal surveillance, but it also improves public health through a community-wide referral process, allowing many people to be connected to health-promoting resources. This protocol is applicable to other public health crises due to its broad, city-wide surveillance and mitigation efforts, reduction of barriers to maximize participation, and incorporation of community voice. The FR protocol was designed in concert with the community, and community engagement remains a priority. Future work includes a diversified community engagement approach, ongoing enrollment, referrals, surveillance, and mitigation efforts.

Efforts to improve and sustain water, sanitation, hygiene (WASH), waste management, and cleaning services in healthcare facilities in low- and middle-income countries are constrained by limited funding. Assessments of the costs of delivering WASH services are critical for guiding financial planning and investment, but many countries lack costed plans for WASH in healthcare facilities. A 2023 UNC Water and Health Conference workshop explored how policymakers and practitioners collect and use cost data and identify strategies for overcoming cost barriers. Presenters shared case studies that showcased the utility of cost data for creating national costed roadmaps, identifying and addressing budgetary shortfalls, and planning WASH improvements in Nepal, Uganda, and Zimbabwe. In discussions, workshop participants described leveraging collaborations with multiple government entities and non-governmental organizations (NGOs) to collect cost data. Participants also reported using cost data to plan programs and advocate for additional WASH funding. Strategies to coordinate costing approaches across stakeholder groups and standardize data collection tools will enhance the efficiency and effectiveness of planning and budgeting for WASH in healthcare facilities. HighlightsO_LILocal and national governments and NGOs routinely collect and use cost data to inform decisions about WASH services in healthcare facilities C_LIO_LIWASH responsibilities are divided across multiple institutions, necessitating coordination for cost data collection C_LIO_LIGovernments have used costing data to create national costed roadmaps and budgets C_LIO_LICosting data support program planning, monitoring, and advocacy C_LI

BackgroundWeather extremes are predicted to influence pathogen exposure but their effects on specific fecal-oral transmission pathways are not well investigated. We evaluated effects of extreme rain and temperature during different antecedent periods (0-14 days) on E. coli along eight fecal-oral transmission pathways in rural Bangladeshi households. MethodsE. coli was enumerated in mother and child hand rinses, food, stored drinking water, tubewells, flies, ponds, and courtyard soil using IDEXX Quanti-Tray/2000 in nine rounds over 3{middle dot}5 years (n=26,659 samples) and spatiotemporally matched to daily weather data. We used generalized linear models with robust standard errors to estimate E. coli count ratios (ECRs) associated with extreme rain and temperature, defined as >90th percentile of daily values during the study period. FindingsControlling for temperature, extreme rain on the sampling day was associated with increased E. coli in food (ECR=3{middle dot}13 (1{middle dot}63, 5{middle dot}99), p=0{middle dot}001), stored drinking water (ECR=1{middle dot}98 (1{middle dot}36, 2{middle dot}88), p<0{middle dot}0005) and ponds (ECR=3{middle dot}46 (2{middle dot}34, 5{middle dot}11), p<0{middle dot}0005), and reduced E. coli in soil (ECR=0{middle dot}36 (0{middle dot}24, 0{middle dot}53), p<0{middle dot}0005). Extreme rain the day before sampling was associated with reduced E. coli in tubewells (ECR=0{middle dot}10 (0{middle dot}02, 0{middle dot}62), p=0{middle dot}014). Effects were similar for rainfall 1-7 days before sampling and slightly attenuated for rainfall 14 days before sampling. Controlling for rainfall, extreme temperature on the sampling day was associated increased E. coli in stored drinking water (ECR=1{middle dot}49 (1{middle dot}05, 2{middle dot}12), p=0{middle dot}025) and food (ECR=3{middle dot}01 (1{middle dot}51, 6{middle dot}01), p=0{middle dot}002). Rainfall/temperature was not consistently associated with E. coli on hands and flies. InterpretationIn rural Bangladesh, measures to control enteric infections following weather extremes should focus on reducing contamination of drinking water and food stored at home and reducing exposure to surface waters. FundingBill & Melinda Gates Foundation, National Institutes of Health, World Bank. Research in Context Evidence before this studyHigher temperatures and levels of rainfall are associated with increased waterborne and vector-borne disease incidence, including child diarrhea. However, the specific pathways that facilitate increased transmission of diarrheagenic pathogens under these weather conditions have not been well investigated. We searched Google Scholar for articles published since 2000 using the following search terms: ("climate change" OR weather OR temperature OR heatwave OR rainfall OR precipitation) AND (pathogen OR enteropathogen OR "Escherichia coli" OR "E. coli" OR "fecal indicator" OR "fecal contamination") AND (environment OR water OR hands OR food OR soil OR flies). A large body of literature has evaluated the effect of rainfall or temperature on water quality and generally found that higher temperatures and magnitudes of rainfall were associated with higher levels of fecal indicator bacteria, such as Escherichia coli (E. coli), in surface and groundwaters, public and private drinking water sources and drinking water stored at homes. However, studies on the impact of rainfall and temperature on fecal contamination along non-waterborne fecal-oral transmission pathways are limited. Contamination of food stored at home has been linked to storage temperature. We found only one study on hand contamination with respect to weather, which found lower E. coli counts on child hands when daily temperatures were higher but no effect from rain. No studies have simultaneously assessed the effects of weather events on a comprehensive set of fecal-oral transmission pathways, which are typically described with the F-diagram and can include drinking water (at the source or stored), surface waters, caregiver and child hands, food, soil and flies. Added value of this studyWe spatiotemporally matched historical meteorological data to over 26,000 E. coli measurements collected in nine rounds over 3{middle dot}5 years in a randomized controlled trial in rural Bangladesh. E. coli was measured across eight different pathogen transmission pathways in the domestic environment. To our knowledge, this study is the first to utilize a large longitudinal dataset of environmental measurements collected over multiple years to investigate how increased rainfall and temperature affect fecal contamination across the full span of pathways described by the F-diagram. Our findings can help identify fecal-oral transmission pathways that are the most susceptible to extreme weather events and should be prioritized for intervention in their wake, as well as offer guidance on the time windows when interventions should be implemented with respect to weather events to interrupt these pathways in the context of climate change. This study can inform the effective delivery of WASH interventions, supporting climate change adaptation to reduce the enteric disease burden associated with weather extremes. Implications of all the available evidenceExtreme rainfall within two weeks of sampling was associated with increased E. coli contamination in stored food, stored drinking water and ponds, and reduced contamination of tubewell water and courtyard soil. Extreme temperature during the same timeframe was associated with increased contamination of stored food and stored drinking water. These findings illuminate environmental mechanisms behind previously reported increases in diarrheal diseases associated with extreme rainfall and temperature. Our findings suggest that, as extreme weather events become more common with climate change, intervention efforts to control exposure to fecal contamination in rural Bangladesh should prioritize reducing contamination of stored food and drinking water as well as reducing exposure to contaminated surface waters.

Universal access to safely managed water, defined as water from an improved source that is accessible on premises, available when needed, and free from contamination, remains far off in many low-resource settings. Progress toward safely managed services may include intermediate steps focused on improving some service attributes over others. However, knowledge surrounding households service preferences remains limited. This study explored satisfaction with existing water service characteristics and willingness-to-pay for hypothetical improvements in water supply. We conducted surveys with 1,748 households among 120 rural communities in northern Ghana. While few households (<2%) had safely managed water services, approximately half (52%) had at least basic access (i.e., an improved source where collection time is within 30 minutes). Satisfaction with existing water services was associated with source type, accessibility, availability, and perceived safety. For example, respondents who always had drinking water available in sufficient quantities had almost three times the odds of being satisfied (odds ratio [OR]: 2.66, 95% CI: 1.94-3.66), similar to respondents able to collect water within 30 minutes (OR: 3.09, 95% CI: 2.28-4.19) and those with on-premises water access (OR: 2.90, 95% CI: 1.26-6.66). Accessibility and water quality were particularly high priorities. Using discrete choice experiments, we estimated participants were willing to pay 3.6-4.9 times more for on-premises piped connections (compared with handpumps 30 minutes away) and chlorination (compared with no treatment). To a lesser extent, households were willing to pay for improved reliability, increased availability, and shorter collection times (10 vs. 30 minutes). Accordingly, we considered the possibility of introducing an intermediate service level: "proximate access", defined as using an improved source where water is collected within 10 minutes, available when needed, and (possibly) free from contamination. Such a category may provide feasible intermediate improvements to advance progress toward more highly valued safely managed services in rural, low-resource settings.

Flushing of water is recommended to prevent the growth of opportunistic pathogens, corrosion, and deterioration of the water supply network during short-term lockdowns. However, the efficacy of flushing fixtures in water supply networks with intermittent gravity-fed supply during long-term lockdowns is unknown. A laboratory-scale premise water supply network with a secondary storage tank connected to a gravity-fed drinking water distribution network was operated for 52 weeks to compare the efficacy of flushing water once a day (1D) vs. once in three days (3D) to preserve water quality. The tap water sampled from buildings (building) and overhead tanks (OHTs) prior to the pandemic served as a benchmark for comparison. The water quality trended as 1D = 3D < building < OHTs, with both the 1D and 3D yielding poor quality water. The water in 3D had higher levels of 16S rRNA gene copies, sul1, and intI1 relative to 1D; this difference was more pronounced (2-3 orders of magnitude) during summer. The levels of sul1, intI1, and DNA marker of Legionella pneumophila in biofilms sampled at the end of the operation of the laboratory-scale premise water supply network trended as elbows > visibly corroded pipes-sections > taps. The levels of heavy metals in some tap water samples exceeded the WHO recommendations and BIS standards for drinking water: 32% of 1D samples (30/93), and 31% of 3D samples (29/93) exceeded the standards for Pb, (10 ppb); while 48% (45/93) of 1D samples and 35% (33/93) of 3D samples exceeded the standards for Fe in drinking water (300 ppb).

People with disabilities face significant disparities in access to water, sanitation, and hygiene (WASH) services, negatively affecting their health. Climate change exacerbates this by damaging WASH infrastructure and disrupting behaviours. Despite their heightened vulnerability, the needs of people with disabilities are often overlooked in climate change response strategies, putting them at greater risk. This study explored how climate change impacts WASH services and behaviours and whether climate-resilient WASH interventions are disability-inclusive and gender-equitable in low--and middle-income countries. Nine online databases were searched in July 2023 and May 2024 to identify peer-reviewed papers (CINAHL Complete, Embase, Global Health; Web of Science; ECONLIT; DESASTRES, GreenFILE, MEDLINE via PubMed, ERIC - Education Resources Information Centre). Grey literature was identified through OPENGrey, WHO, AHRQ, BASE and Google Scholar. Eligible papers included data on the impact of weather or climate on WASH services and behaviours, particularly for people with disabilities and women. Studies focused on community-based WASH interventions in LMICs and were published between 2000 and 2023 in English. Twenty-two studies were included. Thirteen included results about women and girls; two considered disability. Only two evaluated climate-resilient WASH interventions (rainwater harvesting), and neither focused on disability. Most studies examined rainfall uncertainty and drought, covering diverse locations, including South Asia and East Africa. Most studies were published after 2020. Results show that climate change is exacerbating WASH inequalities, particularly affecting women and people with disabilities, while also adversely impacting public health by disrupting water availability, quality, and sanitation services. Variability in rainfall, droughts, floods, and saltwater intrusion significantly affect water reliability, quantity, and quality, leading to increased waterborne diseases, mental health issues, and other health problems. Social capital and kinship networks are critical during water scarcity. People with disabilities are especially vulnerable, often relying on people feeling morally obligated to support water collection. To cope, people diversify their water sources and prioritise water use for agriculture and livelihood security over hygiene, which elevates health risks. Extreme weather events further complicate the situation by damaging sanitation facilities, leading to increased open defecation and the spread of diseases. Rebuilding sanitation facilities is often deprioritised due to repeated damage, mental fatigue of constant reconstruction, and immediate survival needs. Water is frequently prioritised for agriculture over proper sanitation and hygiene practices, resulting in higher rates of open defecation and declining hygiene, as water use for handwashing, cleaning utensils, laundry, and menstrual hygiene is restricted. Consuming saline water is associated with high blood pressure, hypertension, pre-eclampsia, and respiratory infections. Women and girls who wash menstrual materials and bathe in saline water risk skin burns, rashes, blisters, and urinary tract infections. The role of governments and service providers in facilitating adaptation was inconsistent, with a lack of focus on community engagement and equitable service delivery. Climate change disproportionately impacts vulnerable populations access to WASH services. This review highlights the urgent need for research on climate-resilient WASH interventions, especially those addressing the needs of people with disabilities. Targeted support, sustainable management, and robust evidence are essential to building resilience and equality.

IntroductionWastewater-based epidemiology (WBE) was implemented at the 2024 Republican and Democratic National Conventions (RNC and DNC, respectively)--two prominent large-scale events, each with estimated attendances of >50,000 persons. In preparation for event monitoring, the Wisconsin and Chicago WBE programs (associated with the RNC and DNC public health response, respectively) developed site-specific monitoring strategies and response plans, prioritized additional pathogens for event surveillance, and further optimized laboratory workflows to ensure rapid daily data reporting to public health. The Chicago program expanded the sewer sampling network to include new locations closer to event venues than previously available. Sampling was also conducted before the events, to establish baselines for endemic pathogens, as well as after each event to monitor for residual community transmission. MethodsSurveillance was expanded from the four respiratory pathogens regularly assessed by both WBE programs (SARS-CoV-2, influenza A, influenza B, respiratory syncytial virus) to include 3 gastrointestinal pathogens (norovirus, Salmonella enterica, Shiga toxin-producing E. coli). The Wisconsin program also conducted monitoring for the measles, mumps, rubella, and hepatitis A viruses. Wastewater sampling for the RNC was conducted at the community water reclamation facility level, while at the DNC samples were collected from manholes located downstream of the event venues. For both events, WBE data were summarized and contextualized alongside traditional public health surveillance data in daily situation reports. ResultsBetween the RNC and DNC response, a total of 112 wastewater samples were collected and assayed to provide concentration data on as many as 11 distinct pathogens of interest. Concentration results for the suite of pathogens were available within 12 to 36 hours of sample collection. In each instance when wastewater concentrations exceeded pre-established thresholds for action and flagged as an alert, other sources of contemporaneous public health surveillance information (e.g., clinical data) did not corroborate the WBE findings. ConclusionExisting WBE infrastructure in two U.S. cities was readily adapted for public health surveillance at two high-profile, large-scale events. Assays for additional event-relevant pathogens were quickly incorporated into routine laboratory workflows and data from wastewater samples were generated and reported with rapid turnaround-time. In considering the unique benefits of wastewater data, WBE results were a valuable supplement to other public health surveillance data in monitoring potential public health threats during these two large-scale events.

BackgroundWastewater monitoring is a valuable tool to track community-level disease trends. However, the extent to which vulnerable populations have been included in statewide wastewater monitoring programs remains unstudied. ObjectivesWe conducted a geospatial analysis to examine (1) the representativeness of wastewater data collected through the North Carolina Wastewater Monitoring Network as of June 2022, and (2) the potential of wastewater data to generalize to unsewered populations in the county. MethodsAfter intersecting wastewater treatment plant (WWTP) service areas (sewersheds) with census block and tract boundaries for 38 WWTPs across 18 counties, we compared the demographics and social vulnerability of (1) people residing in sewersheds of monitored WWTPs with countywide and statewide populations, and (2) people connected to any sewer system--regardless of inclusion in wastewater monitoring--with unsewered populations. We flagged differences greater than +/-5 percentage points or percent (for categorical and continuous variables, respectively) and noted which were statistically significant (i.e., greater than twice the margin of error). ResultsAs a whole, populations in monitored sewersheds resembled the statewide population on most demographics analyzed, with a few exceptions. When multiple WWTPs were monitored within a county, their combined service populations resembled the countywide population, although populations in individually monitored sewersheds sometimes differed from the countywide population. In nine counties for which we had comprehensive sewershed maps, we found that sewered residents had higher social vulnerability, a greater share of Hispanics and African Americans, lower income, and lower educational attainment than unsewered residents. DiscussionOur results suggest that wastewater monitoring in North Carolina well represents the larger community. Ongoing analyses will be needed as sites are added or removed. The approach we present here can be used to ensure that wastewater surveillance programs nationwide are implemented in a manner that informs equitable public health decision-making.

BackgroundWidespread use of at-home COVID-19 tests hampers determination of community COVID-19 incidence. Using nationwide data available through the US National Wastewater Surveillance System, we examined the performance of two wastewater metrics in predicting high case and hospitalizations rates both before and after widespread use of at-home tests. MethodsWe performed area under the receiver operating characteristic (ROC) curve analysis (AUC) for two wastewater metrics--viral concentration relative to the peak of January 2022 ("wastewater percentile") and 15-day percent change in SARS-CoV-2 ("percent change"). Dichotomized reported cases ([&ge;] 200 or <200 cases per 100,000) and new hospitalizations ([&ge;] 10 or <10 per 100,000) were our dependent variables, stratified by calendar quarter. Using logistic regression, we assessed the performance of combining wastewater metrics. ResultsAmong 268 counties across 22 states, wastewater percentile detected high reported case and hospitalizations rates in the first quarter of 2022 (AUC 0.95 and 0.86 respectively) whereas the percent change did not (AUC 0.54 and 0.49 respectively). A wastewater percentile of 51% maximized sensitivity (0.93) and specificity (0.82) for detecting high case rates. A model inclusive of both metrics performed no better than using wastewater percentile alone. The predictive capability of wastewater percentile declined over time (AUC 0.84 and 0.72 for cases for second and third quarters of 2022). ConclusionNationwide, county wastewater levels above 51% relative to the historic peak predicted high COVID rates and hospitalization in the first quarter of 2022, but performed less well in subsequent quarters. Decline over time in predictive performance of this metric likely reflects underreporting of cases, reduced testing, and possibly lower virulence of infection due to vaccines and treatments.

BackgroundAntibiotic resistance is a leading cause of death, with the highest burden in low-resource settings. There is limited evidence on the potential for water, sanitation, and hygiene (WASH) infrastructure to reduce the burden of antibiotic resistance in humans. MethodsWe used geospatially tagged human gut metagenomes and household survey datasets to determine the association between antibiotic resistance gene (ARG) abundance and community-level coverage of improved drinking water points and improved sanitation facilities. Adjusted general linearized models with robust standard errors were used to estimate the relationship between ARG abundance in the human gut and access to water and sanitation. FindingsWe identified 1589 publicly available metagenomes from 26 countries. The average abundance of ARGs, in units of log10 ARG reads per kilobase per million (RPKM) mapped reads classified as bacteria, was highest in Africa compared to other World Health Organization (WHO) regions (one-way ANOVA p<0.001, post hoc Tukey HSD p<0.05). Increased access to both improved water and sanitation was associated with lower ARG abundance (effect estimate: -0.26, 95% CI [-0.44, -0.08]); the association was stronger in urban (-0.37 [-0.68, -0.07]) compared to rural areas (-0.16 [-0.38, 0.07]). Improved sanitation alone was associated with reduced ARG abundance (-0.16 [-0.32, 0.00]) while improved drinking water was not (-0.09 [-0.35, 0.16]). InterpretationWhile additional studies to investigate casual effects are needed, increasing access to water and sanitation could be an effective strategy to curb the proliferation of antibiotic resistance in low- and middle-income countries. FundingBill & Melinda Gates Foundation Research in ContextO_ST_ABSEvidence before this studyC_ST_ABSAntibiotic resistance is a growing global health threat that disproportionately affects low- and middle-income countries (LMICs). In 2019, an estimated 5 million deaths were associated with antibiotic resistance, with the highest death rate in western sub-Saharan Africa. Water, sanitation, and hygiene (WASH) interventions (e.g., household drinking water treatment, flush toilet, hand washing facilities with soap) can reduce diarrheal and respiratory infections, as reported in previous meta-analyses. Estimates, based on probability modeling, suggest improvements in water and sanitation could decrease antibiotic use for diarrheal disease treatment by 47-50% and 69-72%, respectively. Improving WASH infrastructure could theoretically contribute to the control of antibiotic resistance by preventing the release of antibiotics, resistant organisms, or antibiotic resistance genes (ARGs) into the environment, thus decreasing the burden of antibiotic-resistant infections. One global analysis across 73 countries suggested that improved infrastructure, including WASH services, was associated with reduced antibiotic resistance prevalence in isolates, however the independent effect of WASH access was not assessed. We searched PubMed for evidence on the impact of WASH interventions (excluding those related to animals and agriculture) on antibiotic resistance using the following keyword chain: (water OR sanitation OR hygiene OR WASH) AND (antimicrobial OR antibiotic) AND resistance) NOT ("OneHealth" OR "One Health" OR animal OR livestock). We selected reviews and systematic reviews (n=1420) to be screened for relevance to WASH and antibiotic resistance. The reference lists of included reviews were then searched for individual studies. We also consulted international agency guidelines and online resources from the Joint Programming Initiative on Antimicrobial Resistance, the International Scientific Forum on Hygiene, ReAct, Resistomap, and the London School of Hygiene and Tropical Medicine AMR Centre. Studies focusing on centralized water or wastewater treatment technologies in high income countries (HICs) reported variable removal of antibiotics (53 to >90%), antibiotic-resistant bacteria (90-99.9%) and ARGs (90-99.9%) from waste streams. Other studies were conducted on hand hygiene, which has proven effective at reducing human infections and antibiotic use. No studies were identified on the effect of on-site sanitation systems (e.g., pour-flush toilets, pit latrines), which serve an estimated 2.7 billion people globally, or fecal sludge management interventions on antibiotic resistance. Added value of this studyIn this study, we used 1589 publicly available human gut metagenomes from around the world to assess the abundance of ARGs as a function of access to improved drinking water and sanitation infrastructure. This analysis provides new evidence of differences in the abundance of antibiotic resistance in the human gut across the world and finds that decreased gut abundance of ARGs is associated with increased access to improved drinking water and sanitation. Implications of all the available evidenceCurrent approaches to controlling antibiotic resistance in humans predominantly focus on antibiotic stewardship; however, this approach is challenging in LMICs where infectious illnesses are generally more prevalent and unregulated antibiotic usage is common. Along with efforts to provide other known social benefits, such as reducing infectious disease and improving gender equality, improving access to safe drinking water and sanitation could contribute to reducing the burden of antibiotic resistance. This work highlights improving access to adequate water and sanitation as a potentially effective strategy, although additional studies designed to rigorously investigate the casual relationship between WASH and antibiotic resistance are needed.

Placenta-related complications such as pre-eclampsia, small-for-gestational-age (SGA) and stillbirth contribute significantly to maternal and perinatal mortality globally, with the highest burden in low- and middle-income countries (LMICs). The potential impact of inadequate access to household water, sanitation, and hygiene (WASH) on these outcomes has not been quantified. This study investigates the association between household WASH conditions and pre-eclampsia, stillbirth and SGA in The Gambia, Kenya, and Mozambique, where access to safe WASH services remains a challenge. This study is nested within the PRECISE (PREgnancy Care Integrating Translational Science, Everywhere) study, a prospective observational cohort including 5,745 unselected pregnant women. Multivariate logistic regression analysis was used to test the associations between household WASH and pre-eclampsia, SGA or stillbirth. Compared to women with piped water in their homes, those relying on other improved water sources had higher odds of experiencing selected placenta-related complications (adjusted odds ratio (aOR) 1.36 [95% confidence interval (CI) 1.18, 1.57], p < 0.001). Country-specific analyses revealed differences across settings. In both The Gambia (1.52 [1.03, 2.24], p = 0.034) and Kenya (1.29 [1.04, 1.59], p = 0.019), the use of other improved water sources was associated with increased odds of selected placenta-related complications. Unimproved sanitation, compared with improved sanitation, was associated with increased odds of selected placenta-related complications in Mozambique (1.35 [1.02, 1.80], p = 0.038). The findings highlight the role of household-level WASH conditions as potential risk factors for placenta-related complications. Even when water sources are improved, contamination can occur during collection, transport and storage, while unimproved sanitation can increase pathogen exposure. These results underline the need for targeted WASH interventions to reduce pregnancy-related risks. Addressing these gaps could significantly reduce the prevalence of placenta-related complications, contributing to improved maternal and neonatal health outcomes in LMICs. Future research should explore the mechanisms linking WASH to pre-eclampsia, SGA and stillbirth and other placenta-related complications, and assess the effect of comprehensive WASH interventions.

BackgroundTargeted water treatment and hygiene (WASH) programs for those residing near to diarrhea patients can serve as a cost-effective approach during outbreaks to reduce the spread of diarrhea by targeting those at highest risk. Our research team designed the WASHmobile mobile health (mHealth) program for those at high risk of diarrhea. In our randomized controlled trials in the Democratic Republic of the Congo (DRC) (PICHA7) and Bangladesh (CHoBI7), delivery of WASHmobile to diarrhea patient households through a healthcare facility visit and voice and SMS messages from a doctor significantly reduced diarrhea and improved child growth. MethodsBuilding on this work, we adapted WASHmobile to serve millions more beneficiaries through a mHealth and e-voucher program delivered in diarrhea outbreak areas. A program evaluation of this approach was conducted in health areas (health administrative unit) with ongoing diarrhea outbreaks in the DRC among 2022 participants. Voice and SMS messages were sent to those within 500 meters of diarrhea patients from a doctor stating that there was a diarrhea outbreak in their health area and emphasized the importance of treating and safely storing household drinking water and washing handwashing with soap for the next 7-day high-risk period. The SMS messages contained an e-voucher to redeem for free chlorine tablets at a pharmacy. Unannounced spot checks assessed WASH behaviors a week after program initiation. ResultsFifty-seven percent of WASHmobile households redeemed e-vouchers for chlorine tablets at pharmacies. Compared to control households, WASHmobile households that redeemed e-vouchers had higher stored drinking water with free chlorine concentrations >0.2 mg/L (Odds Ratio [OR]: 6.93, [95% Confidence Interval [CI]: 1.76, 27.24]) (64% [WASHmobile] vs. 20% [control]) and stored drinking water completely covered (OR: 4.55, 95% CI: 2.68, 7.70) (73% vs. 38%). Presence of a cleansing agent within 10 steps of latrine and cooking areas was also significantly higher in WASHmobile households (latrine: OR: 3.64, 95% CI: 1.47, 9.02 [70% vs. 39%] and cooking: OR: 2.50, 95% CI: 1.31, 4.77 [70% vs. 49%]). ConclusionsThe WASHmobile PICHA7 mHealth and e-voucher program significantly increased water treatment, safe water storage, and hygiene behaviors in diarrhea outbreak areas in the DRC.

BackgroundSchools are high-risk settings for SARS-CoV-2 transmission, but necessary for childrens educational and social-emotional wellbeing. Previous research suggests that wastewater monitoring can detect SARS-CoV-2 infections in controlled residential settings with high levels of accuracy. However, its effective accuracy, cost, and feasibility in non-residential community settings is unknown. MethodsThe objective of this study was to determine the effectiveness and accuracy of community-based passive wastewater and surface (environmental) surveillance to detect SARS-CoV-2 infection in neighborhood schools compared to weekly diagnostic (PCR) testing. We implemented an environmental surveillance system in nine elementary schools with 1700 regularly present staff and students in southern California. The system was validated from November 2020 - March 2021. FindingsIn 447 data collection days across the nine sites 89 individuals tested positive for COVID-19, and SARS-CoV-2 was detected in 374 surface samples and 133 wastewater samples. Ninety-three percent of identified cases were associated with an environmental sample (95% CI: 88% - 98%); 67% were associated with a positive wastewater sample (95% CI: 57% - 77%), and 40% were associated with a positive surface sample (95% CI: 29% - 52%). The techniques we utilized allowed for near-complete genomic sequencing of wastewater and surface samples. InterpretationPassive environmental surveillance can detect the presence of COVID-19 cases in non-residential community school settings with a high degree of accuracy. FundingCounty of San Diego, Health and Human Services Agency, National Institutes of Health, National Science Foundation, Centers for Disease Control

BACKGROUNDFew countries are likely to achieve universal sanitation within the next decade as sustaining sanitation coverage remains a critical challenge. The purpose of this study is to investigate factors that may have supported or hindered sustainability of sanitation coverage 1-2 years after the completion of an integrated, area-wide sanitation program in four countries. METHODSBetween 2014 and 2018, the SSH4A approach was implemented in 15 countries in Africa and Asia, four of which are included in this qualitative study. We conducted focus group discussions and interviews with beneficiaries, implementors, and decision-makers to identify sustainability factors and used household survey data to characterize sub-national sanitation coverage throughout implementation, and 1-2 years after. RESULTSOur data revealed behavioral, contextual, and service delivery factors that were related to the sustainability of sanitation improvements. Service delivery factors included follow-up hygiene promotion, access to materials (e.g., plastic, cement), local government commitment post-implementation, functioning monitoring systems, uptake of the supply chain by private sector, capacity for innovation. Contextual and behavioral factors included poverty, soil type, road networks, social cohesion, desire for improved latrines, maintenance and cleaning, and knowledge of sanitation benefits. DISCUSSIONThe presence or absence of sustainability factors identified through this research may have implications on where certain programmatic approaches will work, and where adaptations may be required. Through comparing sustainability factors with sub-national slippage rates, we were able to illustrate how local service delivery systems may respond to barriers (e.g., poverty, lack of affordable sanitation options, changes in population density) and enablers (e.g., sufficient resource allocation, passionate leadership, social cohesion). Understanding the programmatic and contextual factors that either drive or hinder long-term sanitation coverage may allow for greater program impact through adapting implementation based on existing challenges in service delivery and context.