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Cholera is a diarrhoeal disease caused by Vibrio cholerae (V. cholerae) bacterium, with strains belonging to serogroups 01 and 0139 causing a huge proportion of the disease. V. cholerae can contaminate drinking water sources and food through poor sanitation and hygiene. This study aimed to identify environmental routes of exposure to V. cholerae within Mukuru informal settlement in Nairobi. We collected nine types of environmental samples (drinking water, flood water, open drains, surface water, shaved ice, raw produce, street food, soil, and public latrine swabs) over 12 months. All samples were analysed for V. cholerae by culture and qPCR, then qPCR-positive samples were quantified using a V. cholerae DNA standard. Data about the frequency of contact with the environment was collected using behavioural surveys. Of the 803 samples collected, 28.5% were positive for V. cholerae by qPCR. However, none were positive for V. cholerae by culture. V. cholerae genes were detected in majority of the environmental water samples (79.3%), including open drains, flood water, and surface water, but were only detected in small proportions of other sample types. Vibrio-positive environmental water samples had higher mean V. cholerae concentrations [2490-3469 genome copies (gc) per millilitre (mL)] compared to drinking water samples (25.6 gc/mL). Combined with the behavioural data, exposure assessment showed that contact with surface water had the highest contribution to the total V. cholerae exposure among children while ingestion of municipal drinking water and street food and contact with surface water made substantial contributions to the total V. cholerae exposure for adults. Detection of V. cholerae in street food and drinking water indicates possible risk of exposure to toxigenic V. cholerae in this community. Exposure to V. cholerae through multiple pathways highlights the need to improve water and sanitation infrastructure, strengthen food hygiene practices, and roll out cholera vaccination.
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Our study aimed at assessing the determinants of hand hygiene and utilisation of bathing facilities in healthcare facilities (HCFs) in the greater Kampala metropolitan area, Uganda. Results indicate that 19.9% of the respondents wished to wash hands and failed while 39.3% faced challenges related to bathing. Failure to wash hands was associated with received information on hand washing (APR = 1.14, 95% CI: 1.06-1.24), using piped water (APR = 0.88, 95%CI: 0.78-0.98) or a well as the main water source at the HCF (APR = 1.21,95% CI: 1.03-1.42). Experiencing challenges of bathing was associated with accessing healthcare services at a hospital (APR = 0.89, 95% CI 0.81-0.97) and using public HCF (APR = 1.10, 95% CI: 1.01-1.120). There is urgent need to improve hand hygiene and bathing facilities though providing reliable water and soap.
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Madres , Abastecimiento de Agua , Atención a la Salud , Femenino , Humanos , Higiene , UgandaRESUMEN
BACKGROUND: During 2014 to 2019, the SaniPath Exposure Assessment Tool, a standardized set of methods to evaluate risk of exposure to fecal contamination in the urban environment through multiple exposure pathways, was deployed in 45 neighborhoods in ten cities, including Accra and Kumasi, Ghana; Vellore, India; Maputo, Mozambique; Siem Reap, Cambodia; Atlanta, United States; Dhaka, Bangladesh; Lusaka, Zambia; Kampala, Uganda; Dakar, Senegal. OBJECTIVE: Assess and compare risk of exposure to fecal contamination via multiple pathways in ten cities. METHODS: In total, 4053 environmental samples, 4586 household surveys, 128 community surveys, and 124 school surveys were collected. E. coli concentrations were measured in environmental samples as an indicator of fecal contamination magnitude. Bayesian methods were used to estimate the distributions of fecal contamination concentration and contact frequency. Exposure to fecal contamination was estimated by the Monte Carlo method. The contamination levels of ten environmental compartments, frequency of contact with those compartments for adults and children, and estimated exposure to fecal contamination through any of the surveyed environmental pathways were compared across cities and neighborhoods. RESULTS: Distribution of fecal contamination in the environment and human contact behavior varied by city. Universally, food pathways were the most common dominant route of exposure to fecal contamination across cities in low-income and lower-middle-income countries. Risks of fecal exposure via water pathways, such as open drains, flood water, and municipal drinking water, were site-specific and often limited to smaller geographic areas (i.e., neighborhoods) instead of larger areas (i.e., cities). CONCLUSIONS: Knowledge of the relative contribution to fecal exposure from multiple pathways, and the environmental contamination level and frequency of contact for those "dominant pathways" could provide guidance for Water, Sanitation, and Hygiene (WASH) programming and investments and enable local governments and municipalities to improve intervention strategies to reduce the risk of exposure to fecal contamination.
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Países en Desarrollo , Escherichia coli , Bangladesh , Teorema de Bayes , Niño , Ciudades , Monitoreo del Ambiente , Heces , Humanos , Saneamiento , Senegal , Uganda , Estados Unidos , ZambiaRESUMEN
BACKGROUND: Health facility deliveries are generally associated with improved maternal and child health outcomes. However, in Uganda, little is known about factors that influence use of health facilities for delivery especially in rural areas. In this study, we assessed the factors associated with health facility deliveries among mothers living within the catchment areas of major health facilities in Rukungiri and Kanungu districts, Uganda. METHODS: Cross-sectional data were collected from 894 randomly-sampled mothers within the catchment of two private hospitals in Rukungiri and Kanungu districts. Data were collected on the place of delivery for the most recent child, mothers' sociodemographic and economic characteristics, and health facility water, sanitation and hygiene (WASH) status. Modified Poisson regression was used to estimate prevalence ratios (PRs) for the determinants of health facility deliveries as well as factors associated with private versus public utilization of health facilities for childbirth. RESULTS: The majority of mothers (90.2%, 806/894) delivered in health facilities. Non-facility deliveries were attributed to faster progression of labour (77.3%, 68/88), lack of transport (31.8%, 28/88), and high cost of hospital delivery (12.5%, 11/88). Being a business-woman [APR = 1.06, 95% CI (1.01-1.11)] and belonging to the highest wealth quintile [APR = 1.09, 95% CI (1.02-1.17)] favoured facility delivery while a higher parity of 3-4 [APR = 0.93, 95% CI (0.88-0.99)] was inversely associated with health facility delivery as compared to parity of 1-2. Factors associated with delivery in a private facility compared to a public facility included availability of highly skilled health workers [APR = 1.15, 95% CI (1.05-1.26)], perceived higher quality of WASH services [APR = 1.11, 95% CI (1.04-1.17)], cost of the delivery [APR = 0.85, 95% CI (0.78-0.92)], and availability of caesarean services [APR = 1.13, 95% CI (1.08-1.19)]. CONCLUSION: Health facility delivery service utilization was high, and associated with engaging in business, belonging to wealthiest quintile and having higher parity. Factors associated with delivery in private facilities included health facility WASH status, cost of services, and availability of skilled workforce and caesarean services.
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Entorno del Parto/estadística & datos numéricos , Centros de Asistencia al Embarazo y al Parto , Parto Obstétrico , Servicios de Salud Materna/organización & administración , Instalaciones Privadas , Instalaciones Públicas , Adulto , Centros de Asistencia al Embarazo y al Parto/economía , Centros de Asistencia al Embarazo y al Parto/normas , Estudios Transversales , Parto Obstétrico/economía , Parto Obstétrico/métodos , Parto Obstétrico/estadística & datos numéricos , Demografía , Femenino , Accesibilidad a los Servicios de Salud , Humanos , Aceptación de la Atención de Salud/estadística & datos numéricos , Embarazo , Instalaciones Privadas/normas , Instalaciones Privadas/estadística & datos numéricos , Instalaciones Públicas/normas , Instalaciones Públicas/estadística & datos numéricos , Servicios de Salud Rural/economía , Servicios de Salud Rural/normas , Servicios de Salud Rural/estadística & datos numéricos , Factores Socioeconómicos , Uganda/epidemiologíaRESUMEN
BACKGROUND: Hand hygiene (HH) among healthcare workers (HCWs) is critical for infection prevention and control (IPC) in healthcare facilities (HCFs). Nonetheless, it remains a challenge in HCFs, largely due to lack of high-impact and efficacious interventions. Environmental cues and mobile phone health messaging (mhealth) have the potential to improve HH compliance among HCWs, however, these remain under-studied. Our study will determine the impact of mhealth hygiene messages and environmental cues on HH practice among HCWs in the Greater Kampala Metropolitan Area (GKMA). METHODS: The study is a cluster-randomized trial, which will be guided by the behaviour centred design model and theory for behaviour change. During the formative phase, we shall conduct 30 key informants' interviews and 30 semi-structured interviews to explore the barriers and facilitators to HCWs' HH practice. Besides, observations of HH facilities in 100 HCFs will be conducted. Findings from the formative phase will guide the intervention design during a stakeholders' insight workshop. The intervention will be implemented for a period of 4 months in 30 HCFs, with a sample of 450 HCWs who work in maternity and children's wards. HCFs in the control arm will receive innovatively designed HH facilities and supplies. HCWs in the intervention arm, in addition to the HH facilities and supplies, will receive environmental cues and mhealth messages. The main outcome will be the proportion of utilized HH opportunities out of the 9000 HH opportunities to be observed. The secondary outcome will be E. coli concentration levels in 100mls of hand rinsates from HCWs, an indicator of recent fecal contamination and HH failure. We shall run multivariable logistic regression under the generalized estimating equations (GEE) framework to account for the dependence of HH on the intervention. DISCUSSION: The study will provide critical findings on barriers and facilitators to HH practice among HCWs, and the impact of environmental cues and mhealth messages on HCWs' HH practice. TRIAL REGISTRATION: ISRCTN Registry with number ISRCTN98148144 . The trial was registered on 23/11/2020.
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Higiene de las Manos/métodos , Telemedicina , Actitud del Personal de Salud , Señales (Psicología) , Adhesión a Directriz , Personal de Salud , Humanos , Control de Infecciones/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , UgandaRESUMEN
BACKGROUND: Improved Water, Sanitation and Hygiene (WASH) in Healthcare facilities (HCFs) is of significant public health importance. It is associated with a reduction in the transmission of healthcare acquired infections (HAIs), increased trust and uptake of healthcare services, cost saving from infections averted, increased efficiency and improved staff morale. Despite these benefits, there is limited evidence on availability of WASH services in HCFs in the Greater Kampala Metropolitan Area (GKMA). This study assessed the availability and status of WASH services within HCFs in the GKMA in order to inform policy and WASH programming. METHODS: A cross-sectional study was conducted in 60 HCFs. Availability of WASH services in the study HCFs was assessed using a validated WASH Conditions (WASHCon) tool comprising of structured interviews, HCF observations and microbial water quality analysis. Data were analysed using Stata 14 software and R software. RESULTS: Overall, 84.5% (49/58) and 12.1% (7/58) of HCFs had limited and basic WASH service respectively. About 48.3% (28/58) had limited water service, 84.5% (49/58) had limited sanitation service, 50.0% (29/58) had limited environmental cleanliness service, 56.9% (33/58) had limited hand hygiene service, and 51.7% (30/58) had limited waste management service. About 94.4% of public HCFs had limited WASH service compared to only 68.2% of private not for profit facilities. More health centre IIIs, 92.5% and health centre IVs (85.7%) had limited WASH service compared to hospitals (54.5%). CONCLUSIONS: Our findings indicate that provision of water, sanitation, hand hygiene, environmental cleanliness, and health care waste management services within HCFs is largely hindered by structural and performance limitations. In spite of these limitations, it is evident that environmental cleanliness and treatment of infectious waste can be attained with better oversight and dedicated personnel. Attaining universal WASH coverage in HCFs will require deliberate and strategic investments across the different domains.
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Instituciones de Salud/estadística & datos numéricos , Higiene , Saneamiento/estadística & datos numéricos , Servicios Urbanos de Salud/estadística & datos numéricos , Abastecimiento de Agua/estadística & datos numéricos , Estudios Transversales , Humanos , UgandaRESUMEN
Inadequate sanitation can lead to exposure to fecal contamination through multiple environmental pathways and can result in adverse health outcomes. By understanding the relative importance of multiple exposure pathways, sanitation interventions can be tailored to those pathways with greatest potential public health impact. The SaniPath Exposure Assessment Tool allows users to identify and quantify human exposure to fecal contamination in low-resource urban settings through a systematic yet customizable process. The Tool includes: a project management platform; mobile data collection and a data repository; protocols for primary data collection; and automated exposure assessment analysis. The data collection protocols detail the process of conducting behavioral surveys with households, school children, and community groups to quantify contact with fecal exposure pathways and of collecting and analyzing environmental samples for E. coli as an indicator of fecal contamination. Bayesian analyses are used to estimate the percentage of the population exposed and the mean dose of fecal exposure from microbiological and behavioral data. Fecal exposure from nine pathways (drinking water, bathing water, surface water, ocean water, open drains, floodwater, raw produce, street food, and public or shared toilets) can be compared through a common metric-estimated ingestion of E. coli units (MPN or CFU) per month. The Tool generates data visualizations and recommendations for interventions designed for both scientific and lay audiences. When piloted in Accra, Ghana, the results of the Tool were comparable with that of an in-depth study conducted in the same neighborhoods and highlighted consumption of raw produce as a dominant exposure pathway. The Tool has been deployed in nine cities to date, and the results are being used by local authorities to design and prioritize programming and policy. The SaniPath Tool is a novel approach to support public-health evidence-based decision-making for urban sanitation policies and investments.
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Microbiología Ambiental , Monitoreo del Ambiente/métodos , Heces/microbiología , Saneamiento/estadística & datos numéricos , Programas Informáticos , Ciudades , Toma de Decisiones , Exposición a Riesgos Ambientales , Monitoreo del Ambiente/estadística & datos numéricos , Escherichia coli/aislamiento & purificación , Contaminación de Alimentos , Ghana , Humanos , Proyectos Piloto , Formulación de Políticas , Pobreza , Salud Pública , Salud Urbana , Microbiología del AguaRESUMEN
Alongside efforts to improve safe management of feces along the entire sanitation chain, including after the toilet, global sanitation efforts are focusing on universal access 'basic' services: onsite facilities that safely contain excreta away from human contact. Although fecal sludge management is improving in urban areas, open drains remain a common fate for feces in these often densely-populated neighborhoods in low-income countries. To-date, it is unclear to what extent complete coverage of onsite sanitation reduces fecal contamination in the urban environment and how fecal contamination varies within urban drains across neighborhoods by sanitation status within a city. We assessed how neighborhood levels of environmental fecal contamination (via spatially-representative sampling of open drains for E. coli) varied across four neighborhoods with varying income, type and coverage of household sanitation facilities, and population density in Accra, Ghana. Neighborhoods with very high sanitation coverage (≥89%) still had high (>4 log10 CFU/100 mL) E. coli concentrations in drains. Between-neighborhood variation in E. coli levels among the high coverage neighborhoods was significant: drain concentrations in neighborhoods with 93% and 89% coverage (4.7 (95% CI: 4.5, 4.9) & 4.9 (95% CI: 4.5, 5.3) log10 CFU/100 mL, respectively) were higher than in the neighborhood with 97% coverage (4.1 log10 CFU/100 mL, 95% CI: 3.8, 4.4 log10 CFU/100 mL). Compared with the highest coverage neighborhood, the neighborhood with lowest coverage (48%) also had higher E. coli concentrations (5.6 log10 CFU/100 mL, 95% CI: 5.3, 5.9 log10 CFU/100 mL). Although fecal contamination in open drains appeared lower in neighborhoods with higher onsite sanitation coverage (and vice versa), other factors (e.g. fecal sludge management, animals, population density) may affect drain concentrations. These results underscore that neighborhood-level onsite sanitation improvements alone may not sufficiently reduce fecal hazards to public health from open drains. These findings supporting the need for integrated, city-level fecal sludge management alongside multifaceted interventions to reduce fecal contamination levels and human exposure.
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Monitoreo del Ambiente , Contaminación Ambiental/estadística & datos numéricos , Escherichia coli , Saneamiento , Composición Familiar , Heces , Ghana , Humanos , Pobreza , Características de la Residencia , Aguas del AlcantarilladoRESUMEN
BACKGROUND: Open drains are common methods of transporting solid waste and excreta in low-income urban neighborhoods. Open drains can overflow due to blockages with solid waste and during rainfall, posing exposure risks. The goal of this study was to evaluate whether pediatric enteric infection was associated with open drains and flooding in a dense, low-income, urban neighborhood. METHODS: As part of the MAL-ED study in Vellore, India, a cohort of 230 children provided stool specimens at 14-17 scheduled home visits and during diarrheal episodes in the first two years of life. All specimens were analyzed for enteric pathogens. Caregivers in 100 households reported on flooding of drains and households and monthly frequency of contact with open drains and flood water. Household GPS points were collected. Monthly rainfall totals for the Vellore district were collected from the Indian Meteorological Department. Clustering of reported drain and house flooding were identified by Kulldorff's Bernoulli Spatial Scan. Differences in enteric infection were assessed for household responses and spatial clusters, with interactions between reported flooding and rainfall to approximate monthly drain flooding retrospectively, using multivariable, mixed-effects logistic regression models. RESULTS: Coverage of household toilets was low (33%), and most toilets (82%) discharged directly into open drains, suggesting poor neighborhood fecal sludge management. Odds of enteric infection increased significantly with total monthly rainfall for children who lived in households that reported that the nearby drain flooded (4% increase per cm of rain: OR: 1.04, 95% CI: 1.00-1.08) and for children in households in a downstream spatial cluster of reported drain flooding (5% increase per cm of rain: OR: 1.05, 95% CI: 1.01-1.09). There was no association between odds of enteric infection and frequency of reported contact with drain or floodwater. CONCLUSIONS: Children in areas susceptible to open drain flooding had increased odds of enteric infection as rainfall increased. Results suggested that infection increased with rainfall due to neighborhood infrastructure (including poor fecal sludge management) and not frequency of contact. Thus, these exposures may not be mitigated by changes in personal behaviors alone. These results underscore the importance of improving the neighborhood environment to improve children's health in low-income, urban settings.
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Infecciones Bacterianas/epidemiología , Inundaciones , Áreas de Pobreza , Características de la Residencia/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Niño , Estudios de Cohortes , Heces/microbiología , Humanos , India/epidemiología , Lluvia , Saneamiento , Aguas del AlcantarilladoRESUMEN
Exposure to fecal contamination in public areas, especially in dense, urban environments, may significantly contribute to enteric infection risk. This study examined associations between sanitation and fecal contamination in public environments in four low-income neighborhoods in Accra, Ghana. Soil (n = 72) and open drain (n = 90) samples were tested for E. coli, adenovirus, and norovirus. Sanitation facilities in surveyed households (n = 793) were categorized by onsite fecal sludge containment ("contained" vs. "uncontained") using previous Joint Monitoring Program infrastructure guidelines. Most sanitation facilities were shared by multiple households. Associations between spatial clustering of household sanitation coverage and fecal contamination were examined, controlling for neighborhood and population density (measured as enumeration areas in the 2010 census and spatially matched to sample locations). E. coli concentrations in drains within 50m of clusters of contained household sanitation were more than 3 log-units lower than those outside of clusters. Further, although results were not always statistically significant, E. coli concentrations in drains showed consistent trends with household sanitation coverage clusters: concentrations were lower in or near clusters of high coverage of household sanitation facilities-especially contained facilities-and vice versa. Virus detection in drains and E. coli concentrations in soil were not significantly associated with clustering of any type of household sanitation and did not exhibit consistent trends. Population density alone was not significantly associated with any of the fecal contamination outcomes by itself and was a significant, yet inconsistent, effect modifier of the association between sanitation clusters and E. coli concentrations. These findings suggest clustering of contained household sanitation, even when shared, may be associated with lower levels of fecal contamination within drains in the immediate public domain. Further research is needed to better quantify these relationships and examine impacts on health.
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Monitoreo del Ambiente , Contaminación Ambiental/análisis , Saneamiento/estadística & datos numéricos , Aguas del Alcantarillado/análisis , Adenoviridae/aislamiento & purificación , Análisis por Conglomerados , Escherichia coli/aislamiento & purificación , Heces/microbiología , Heces/virología , Ghana , Humanos , Norovirus/aislamiento & purificación , Densidad de Población , Pobreza/estadística & datos numéricos , Características de la Residencia , Eliminación de Residuos Líquidos/economía , Eliminación de Residuos Líquidos/métodosRESUMEN
In crowded urban settlements in low-income countries, many households rely on shared sanitation facilities. Shared facilities are not currently considered "improved sanitation" because of concerns about whether hygiene conditions sufficiently protect users from the feces of others. Prevention of fecal exposure at a latrine is only one aspect of sanitary safety. Ensuring consistent use of latrines for feces disposal, especially child feces, is required to reduce fecal contamination in households and communities. Household crowding and shared latrine access are correlated in these settings, rendering latrine use by neighbors sharing communal living areas as critically important for protecting one's own household. This study in Accra, Ghana, found that household access to a within-compound basic latrine was associated with higher latrine use by children of ages 5-12 years and for disposal of feces of children < 5 years, compared with households using public latrines. However, within-compound access was not associated with improved child feces disposal by other caregivers in the compound. Feces was rarely observed in household compounds but was observed more often in compounds with latrines versus compounds relying on public latrines. Escherichia coli and human adenovirus were detected frequently on household surfaces, but concentrations did not differ when compared by latrine access or usage practices. The differences in latrine use for households sharing within-compound versus public latrines in Accra suggest that disaggregated shared sanitation categories may be useful in monitoring global progress in sanitation coverage. However, compound access did not completely ensure that households were protected from feces and microbial contamination.
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Pobreza , Cuartos de Baño/normas , Cuidadores , Composición Familiar , Heces , Femenino , Ghana , Humanos , MadresRESUMEN
Lack of adequate sanitation results in fecal contamination of the environment and poses a risk of disease transmission via multiple exposure pathways. To better understand how eight different sources contribute to overall exposure to fecal contamination, we quantified exposure through multiple pathways for children under 5 years old in four high-density, low-income, urban neighborhoods in Accra, Ghana. We collected more than 500 hours of structured observation of behaviors of 156 children, 800 household surveys, and 1,855 environmental samples. Data were analyzed using Bayesian models, estimating the environmental and behavioral factors associated with exposure to fecal contamination. These estimates were applied in exposure models simulating sequences of behaviors and transfers of fecal indicators. This approach allows us to identify the contribution of any sources of fecal contamination in the environment to child exposure and use dynamic fecal microbe transfer networks to track fecal indicators from the environment to oral ingestion. The contributions of different sources to exposure were categorized into four types (high/low by dose and frequency), as a basis for ranking pathways by the potential to reduce exposure. Although we observed variation in estimated exposure (108-1016 CFU/day for Escherichia coli) between different age groups and neighborhoods, the greatest contribution was consistently from food (contributing > 99.9% to total exposure). Hands played a pivotal role in fecal microbe transfer, linking environmental sources to oral ingestion. The fecal microbe transfer network constructed here provides a systematic approach to study the complex interaction between contaminated environment and human behavior on exposure to fecal contamination.
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Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Heces , Contaminación de Alimentos , Teorema de Bayes , Preescolar , Femenino , Ghana , Humanos , Lactante , Masculino , Pobreza/estadística & datos numéricos , Características de la Residencia/estadística & datos numéricosRESUMEN
Rapid urbanization has contributed to an urban sanitation crisis in low-income countries. Residents in low-income, urban neighborhoods often have poor sanitation infrastructure and services and may experience frequent exposure to fecal contamination through a range of pathways. There are little data to prioritize strategies to decrease exposure to fecal contamination in these complex and highly contaminated environments, and public health priorities are rarely considered when planning urban sanitation investments. The SaniPath Study addresses this need by characterizing pathways of exposure to fecal contamination. Over a 16 month period, an in-depth, interdisciplinary exposure assessment was conducted in both public and private domains of four neighborhoods in Accra, Ghana. Microbiological analyses of environmental samples and behavioral data collection techniques were used to quantify fecal contamination in the environment and characterize the behaviors of adults and children associated with exposure to fecal contamination. Environmental samples (n = 1,855) were collected and analyzed for fecal indicators and enteric pathogens. A household survey with 800 respondents and over 500 hours of structured observation of young children were conducted. Approximately 25% of environmental samples were collected in conjunction with structured observations (n = 441 samples). The results of the study highlight widespread and often high levels of fecal contamination in both public and private domains and the food supply. The dominant fecal exposure pathway for young children in the household was through consumption of uncooked produce. The SaniPath Study provides critical information on exposure to fecal contamination in low-income, urban environments and ultimately can inform investments and policies to reduce these public health risks.
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Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Heces , Contaminación de Alimentos , Población Urbana/estadística & datos numéricos , Teorema de Bayes , Femenino , Ghana , Humanos , Masculino , Pobreza/estadística & datos numéricos , Características de la Residencia/estadística & datos numéricos , Factores Socioeconómicos , UrbanizaciónRESUMEN
AbstractUrban sanitation necessitates management of fecal sludge inside and outside the household. This study examined associations between household sanitation, fecal contamination, and enteric infection in two low-income neighborhoods in Vellore, India. Surveys and spatial analysis assessed the presence and clustering of toilets and fecal sludge management (FSM) practices in 200 households. Fecal contamination was measured in environmental samples from 50 households and household drains. Enteric infection was assessed from stool specimens from children under 5 years of age in these households. The two neighborhoods differed significantly in toilet coverage (78% versus 33%) and spatial clustering. Overall, 49% of toilets discharged directly into open drains ("poor FSM"). Children in households with poor FSM had 3.78 times higher prevalence of enteric infection when compared with children in other households, even those without toilets. In the neighborhood with high coverage of household toilets, children in households with poor FSM had 10 times higher prevalence of enteric infection than other children in the neighborhood and drains in poor FSM clusters who had significantly higher concentrations of genogroup II norovirus. Conversely, children in households with a toilet that contained excreta in a tank onsite had 55% lower prevalence of enteric infection compared with the rest of the study area. Notably, households with a toilet in the neighborhood with low toilet coverage had more fecal contamination on floors where children played compared with those without a toilet. Overall, both toilet coverage levels and FSM were associated with environmental fecal contamination and, subsequently, enteric infection prevalence in this urban setting.
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Heces/microbiología , Saneamiento , Aguas del Alcantarillado/microbiología , Cuartos de Baño , Campylobacter/aislamiento & purificación , Preescolar , Monitoreo del Ambiente , Escherichia coli/aislamiento & purificación , Desinfección de las Manos , Humanos , Higiene , India , Modelos Lineales , Prevalencia , Microbiología del Agua , Abastecimiento de AguaRESUMEN
OBJECTIVE: This study examined associations between household sanitation and enteric infection - including diarrhoeal-specific outcomes - in children 0-2 years of age in a low-income, dense urban neighbourhood. METHODS: As part of the MAL-ED study, 230 children in a low-income, urban, Indian neighbourhood provided stool specimens at 14-17 scheduled time points and during diarrhoeal episodes in the first 2 years of life that were analysed for bacterial, parasitic (protozoa and helminths) and viral pathogens. From interviews with caregivers in 100 households, the relationship between the presence (and discharge) of household sanitation facilities and any, pathogen-specific, and diarrhoea-specific enteric infection was tested through mixed-effects Poisson regression models. RESULTS: Few study households (33%) reported having toilets, most of which (82%) discharged into open drains. Controlling for season and household socio-economic status, the presence of a household toilet was associated with lower risks of enteric infection (RR: 0.91, 95% CI: 0.79-1.06), bacterial infection (RR: 0.87, 95% CI: 0.75-1.02) and protozoal infection (RR: 0.64, 95% CI: 0.39-1.04), although not statistically significant, but had no association with diarrhoea (RR: 1.00, 95% CI: 0.68-1.45) or viral infections (RR: 1.12, 95% CI: 0.79-1.60). Models also suggested that the relationship between household toilets discharging to drains and enteric infection risk may vary by season. CONCLUSIONS: The presence of a household toilet was associated with lower risk of bacterial and protozoal enteric infections, but not diarrhoea or viral infections, suggesting the health effects of sanitation may be more accurately estimated using outcome measures that account for aetiologic agents.
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Infecciones Bacterianas/prevención & control , Diarrea , Enfermedades Intestinales/prevención & control , Pobreza , Infecciones por Protozoos/prevención & control , Cuartos de Baño , Virosis , Adulto , Animales , Infecciones Bacterianas/etiología , Infecciones Bacterianas/microbiología , Preescolar , Estudios de Cohortes , Diarrea/etiología , Disentería/etiología , Disentería/prevención & control , Heces , Helmintiasis/etiología , Helmintiasis/prevención & control , Helmintos , Humanos , Renta , India , Lactante , Recién Nacido , Enfermedades Intestinales/etiología , Enfermedades Intestinales/microbiología , Enfermedades Intestinales/parasitología , Infecciones por Protozoos/etiología , Infecciones por Protozoos/parasitología , Características de la Residencia , Factores de Riesgo , Saneamiento , Población Urbana , Virosis/etiologíaRESUMEN
In low-income countries, rapid urbanization adds pressure to already stressed water and sanitation systems that are critical to the health of communities. Drainage networks, designed for stormwater but commonly used for disposing of waste, are rarely covered completely, allowing residents to easily come into contact with their contents. This study used spatial mapping, documentation of physical drain characteristics, microbiological analysis of drain samples, and behavioral observation to comprehensively examine drains as a route of exposure to fecal contamination in four low-income neighborhoods in Accra, Ghana. A stochastic model of six likely exposure scenarios was constructed to estimate children's exposure to drain water. Regardless of the age of the child, any exposure scenario considered resulted in exposure to a high level of fecal contamination. Fecal contamination levels in drains were high (Escherichia coli: geometric mean (GM), 8.60 cfu log(10)/100 mL; coliphage: GM, 5.56 pfu log(10)/100 mL), and did not differ by neighborhood or physical drain characteristics, indicating that frequency of contact with drains, and not drain type or location, drives exposure risk. To mitigate health risks associated with this exposure, drains should be covered, with priority given to large concrete and small to medium dirt-lined drains that children were most commonly observed entering.
Asunto(s)
Exposición a Riesgos Ambientales , Monitoreo del Ambiente/métodos , Microbiología del Agua , Calidad del Agua , Adolescente , Niño , Preescolar , Colifagos/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Heces/microbiología , Ghana , Humanos , LactanteRESUMEN
To better understand the risks of exposure for young children to fecal contamination in their environment, we systematically characterized and quantified behaviors of 154 children, 0-5 years old, in four high-density, low-income neighborhoods in Accra, Ghana. A repertoire of six different activities and five different compartments (categories of locations within the household) was developed, and about 500 hours of ordered structured observations of activities and locations of individual children were collected. These records were analyzed using a competing hazards model, estimating (Weibull) hazard rates for each state (activity/compartment combination), dependent on the present state and the preceding state. The estimated rates were used to simulate sequences of behavior and describe days in the life of a child in low-income, urban Africa. Children younger than 1 year spent most time playing or sleeping off the ground, older children frequently played on floors. Relatively little time was spent in drains or wet trash areas. Critical combinations of activities, like handwashing after defecation or before eating were estimated to occur rarely. These quantitative behavior estimates can inform future risk assessments that examine the relative roles of various fecal-oral exposure pathways in low-income urban settings.