Waterborne disease outbreaks in treated recreational water facilities: a Socio-Ecological Model perspective.

Treated recreational water facilities, including swimming pools and water play parks, have often been implicated in infectious disease outbreaks. Addressing this problem is complex due to the multiple and interrelated factors contributing to outbreaks in these settings. These factors may relate to inappropriate behaviours of users and operators, lack of and inconsistent regulation of these facilities, insufficient facility maintenance, and problems associated with the design of these facilities. Given the complexity of this issue, we argue that the Socio-Ecological Model (SEM) provides a useful framework to help identify the multi-level influences and factors that have implications for designing interventions to prevent this public health problem, whilst assisting in guiding future research in this area. We apply the SEM to the current literature to help identify the influences and factors contributing to infectious disease outbreaks in treated recreational water facilities to support this argument. We also identify several gaps in the existing research that would benefit from further examination to help prevent infectious disease outbreaks in treated recreational water facilities such as public swimming pools and water play parks.

Prevalence and predictors of water-borne diseases among elderly people in India: evidence from Longitudinal Ageing Study in India, 2017-18.

BACKGROUND: India suffers from a high burden of diarrhoea and other water-borne diseases due to unsafe water, inadequate sanitation and poor hygiene practices among human population. With age the immune system becomes complex and antibody alone does not determine susceptibility to diseases which increases the chances of waterborne disease among elderly population. Therefore the study examines the prevalence and predictors of water-borne diseases among elderly in India. METHOD: Data for this study was collected from the Longitudinal Ageing Study in India (LASI), 2017-18. Descriptive statistics along with bivariate analysis was used in the present study to reveal the initial results. Proportion test was applied to check the significance level of prevalence of water borne diseases between urban and rural place of residence. Additionally, binary logistic regression analysis was used to estimate the association between the outcome variable (water borne diseases) and the explanatory variables. RESULTS: The study finds the prevalence of water borne disease among the elderly is more in the rural (22.5%) areas compared to the urban counterparts (12.2%) due to the use of unimproved water sources. The percentage of population aged 60 years and above with waterborne disease is more in the central Indian states like Chhattisgarh and Madhya Pradesh followed by the North Indian states. Sex of the participate, educational status, work status, BMI, place of residence, type of toilet facility and water source are important determinants of water borne disease among elderly in India. CONCLUSION: Elderly people living in the rural areas are more prone to waterborne diseases. The study also finds state wise variation in prevalence of waterborne diseases. The elderly people might not be aware of the hygiene practices which further adhere to the disease risk. Therefore, there is a need to create awareness on basic hygiene among this population for preventing such bacterial diseases.

Narrative Review of Primary Preventive Interventions against Water-Borne Diseases: Scientific Evidence of Health-EDRM in Contexts with Inadequate Safe Drinking Water.

Waterborne diseases account for 1.5 million deaths a year globally, particularly affecting children in low-income households in subtropical areas. It is one of the most enduring and economically devastating biological hazards in our society today. The World Health Organization Health Emergency and Disaster Risk Management (health-EDRM) Framework highlights the importance of primary prevention against biological hazards across all levels of society. The framework encourages multi-sectoral coordination and lessons sharing for community risk resilience. A narrative review, conducted in March 2021, identified 88 English-language articles published between January 2000 and March 2021 examining water, sanitation, and hygiene primary prevention interventions against waterborne diseases in resource-poor settings. The literature identified eight main interventions implemented at personal, household and community levels. The strength of evidence, the enabling factors, barriers, co-benefits, and alternative measures were reviewed for each intervention. There is an array of evidence available across each intervention, with strong evidence supporting the effectiveness of water treatment and safe household water storage. Studies show that at personal and household levels, interventions are effective when applied together. Furthermore, water and waste management will have a compounding impact on vector-borne diseases. Mitigation against waterborne diseases require coordinated, multi-sectoral governance, such as building sanitation infrastructure and streamlined waste management. The review showed research gaps relating to evidence-based alternative interventions for resource-poor settings and showed discrepancies in definitions of various interventions amongst research institutions, creating challenges in the direct comparison of results across studies.

The role of biofilm in the development and dissemination of ubiquitous pathogens in drinking water distribution systems: an overview of surveillance, outbreaks, and prevention.

A variety of pathogenic microorganisms can survive in the drinking water distribution systems (DWDS) by forming stable biofilms and, thus, continually disseminating their population through the system's dynamic water bodies. The ingestion of the pathogen-contaminated water could trigger a broad spectrum of illnesses and well-being-related obstacles. These waterborne diseases are a significant concern for babies, pregnant women, and significantly low-immune individuals. This review highlights the recent advances in understanding the microbiological aspects of drinking water quality, biofilm formation and its dynamics, health issues caused by the emerging microbes in biofilm, and approaches for biofilm investigation its prevention and suppression in DWDS.

A Whole-Cell Biosensor for Point-of-Care Detection of Waterborne Bacterial Pathogens.

Water contamination by pathogenic bacteria is a major public health concern globally. Monitoring bacterial contamination in water is critically important to protect human health, but this remains a critical challenge. Engineered whole-cell biosensors created through synthetic biology hold great promise for rapid and cost-effective detection of waterborne pathogens. In this study, we created a novel whole-cell biosensor to detect water contamination by Pseudomonas aeruginosa and Burkholderia pseudomallei, which are two critical bacterial pathogens and are recognized as common causative agents for waterborne diseases. The biosensor detects the target bacterial pathogens by responding to the relevant quorum sensing signal molecules. Particularly, this study constructed and characterized the biosensor on the basis of the QscR quorum sensing signal system for the first time. We first designed and constructed a QscR on the basis of the sensing module in the E. coli host cell and integrated the QscR sensing module with a reporting module that expressed an enhanced green fluorescent protein (EGFP). The results demonstrated that the biosensor had high sensitivity in response to the quorum sensing signals of the target bacterial pathogens. We further engineered a biosensor that expressed a red pigment lycopene in the reporting module to produce a visible signal readout for the pathogen detection. Additionally, we investigated the feasibility of a paper-based assay by immobilizing the lycopene-based whole-cell biosensor on paper with the aim to build a prototype for developing portable detection devices. The biosensor would provide a simple and inexpensive alternative for timely and point-of-care detection of water contamination and protect human health.

Mathematical Analyses on the Effects of Control Measures for a Waterborne Disease Model with Socioeconomic Conditions.

Waterborne diseases are present major health problems to humanity especially in rural communities where many individuals belong to the lower socioeconomic classes (SECs). The impacts of introducing waterborne disease control measures for such communities are investigated by considering a waterborne disease model. The model is extended by introducing treatment of infected individuals and water purification as control measures. The possible benefits of considering these control measures for the various SECs are investigated. Further analyses show how different degrees of control impact the rate at which waterborne diseases are spread across SECs. The disease control model is validated by using it to study the cholera outbreak in Haiti.

Vigilância epidemiológica das doenças de transmissão hídrica e alimentar: manual de treinamento / Epidemiological surveillance of water and foodborne diseases: training manual

Este Manual é um instrumento que subsidia o treinamento em vigilância epidemiológica das doenças de transmissão hídrica e alimentar (VE-DTHA), direcionado para profissionais de saúde que atuam na investigação de surtos ou de casos de doenças de notificação compulsória relacionadas à transmissão hídrica e alimentar.

Efficacy and Effectiveness of Showerheads Attached with Point-of-use (POU) Filter Capsules in Preventing Waterborne Diseases in a Japanese Hospital.

Tap water contamination is a growing concern in healthcare facilities, and despite chlorination, tap water in these facilities contains several pathogenic microorganisms causing healthcare-associated waterborne infections or nosocomial outbreaks. Shower units are particularly prone to contamination as they are conducive for bacterial growth and can even produce bioaerosols containing pathogenic bacteria. Shower units coupled with point-of-use (POU) water filters are a simple and safe option; however, their efficacy has been under-reported. Therefore, we determined the efficacy of showerheads attached with a POU filter capsule in preventing infections in our hospital. We investigated the presence of pathogenic bacteria in water sampled from three shower units. After replacing the original shower units with new ones incorporated with a sterile-grade water filter capsule (0.2 µm; QPoint™), the water samples were analyzed for up to 2 months. The POU filters removed several pathogenic bacteria (Mycobacterium, Pseudomonas, Stenotrophomonas, Aeromonas, and Klebsiella spp.). Filter effectiveness depends on regional water quality and we believe that effective tap water treatment combined with the use of POU filters (introduced at a reasonable cost in healthcare facilities) can considerably minimize waterborne diseases in hospitals and improve patient care.

Enfermedades de transmisión hídricas en el cantón Penipe, Ecuador 2016-2017 / Waterborne diseases in cantón Penipe, Ecuador, 2016-2017

Introducción: La reemergencia y el control de algunas enfermedades de transmisión hídrica continúan siendo motivos de interés para los gobiernos sanitarios. Objetivo: Desarrollar acciones intersectoriales dirigidas al mejoramiento de la situación ambiental, el saneamiento básico y la calidad del agua. Métodos: Se desarrolló una investigación-acción participativa, con enfoque mixto. Se conformó un equipo multidisciplinario integrado por profesionales de la salud, miembros de la comunidad y del Gobierno Autónomo Descentralizado de Penipe, Chimborazo, Ecuador. La población estuvo constituida por 2089 habitantes que residían de forma permanente en el área urbana de la cabecera cantonal durante septiembre de 2016 y septiembre de 2017. La muestra (494 personas) se seleccionó por muestreo no probabilístico, la integraron individuos con edades entre 15 y 60 años, mentalmente aptos y que en el momento de la aplicación del instrumento se encontraban en su vivienda. Estas personas ofrecieron su consentimiento informado de participación y declararon residir de forma permanente en esa localidad. Para la recolección de los datos se empleó un cuestionario diseñado y validado por criterio de especialistas. Resultados: Predominaron las féminas de 21-30 años de edad y la autoidentificación étnica de mestiza. El consumo de agua hervida y su cloración constituyeron las prácticas más referidas por los encuestados, lo que resulta insuficiente para evitar la transmisibilidad de las enfermedades de transmisión hídrica. Conclusiones: La presencia de las enfermedades de transmisión hídricas en el cantón Penipe, Ecuador es un problema de la salud pública local que aún no ha sido resuelto, lo que justifica una intervención intersectorial que permita una educación para la salud incluyente, renovada y de carácter comunitario(AU)

Introduction: Re-emergence and control of some waterborne diseases are still an interest for sanitary governments. Objective: To develop intersectoral actions addressed to the improvement of the environmental situation, the basic sanitation and water quality. Methods: It was developed a participative research-action, with mixed approach. It was formed a multidisciplinary team made up by health professionals, members of the community and the Decentralized Autonomous Government of Penipe, Cimborazo, Ecuador. The population was formed by 2089 inhabitants living permanently in the urban area of the cantonal administrative center in the period from September 2016 to September 2017. The sample (494 people) was selected by non-probabilistic sampling, and it was made up by individuals in the ages from 15 to 60 years, mentally fit and that at the moment of the instrument's implementation were at their house. These people gave their informed consent for participating and declared to live permanently in that area. For data collection, it was used the questionnaire designed and validated by specialists criterion. Results: Females in the ages from 21 to 30 years and the ethnic auto-identification as mixed race predominated. Consumption of boiled water and its chlorination were the most common practices referred by those polled, which is insufficient to avoid transmissibility of waterborne diseases. Conclusions: The presence of water transmission diseases in cantón Penipe, in Ecuador is an unsolved local public health problem which justifies an intersectoral intervention that allows an inclusive, renewed and community focused health education(AU)

Impact of Low-Cost Point-of-Use Water Treatment Technologies on Enteric Infections and Growth among Children in Limpopo, South Africa.

Enteric infections early in life have been associated with poor linear growth among children in low-resource settings. Point-of-use water treatment technologies provide effective and low-cost solutions to reduce exposure to enteropathogens from drinking water, but it is unknown whether the use of these technologies translates to improvements in child growth. We conducted a community-based randomized controlled trial of two water treatment technologies to estimate their effects on child growth in Limpopo, South Africa. We randomized 404 households with a child younger than 3 years to receive a silver-impregnated ceramic water filter, a silver-impregnated ceramic tablet, a safe-storage water container alone, or no intervention, and these households were followed up quarterly for 2 years. We estimated the effects of the interventions on linear and ponderal growth, enteric infections assessed by quantitative molecular diagnostics, and diarrhea prevalence. The silver-impregnated ceramic water filters and tablets consistently achieved approximately 1.2 and 3 log reductions, respectively, in total coliform bacteria in drinking water samples. However, the filters and tablets were not associated with differences in height (height-for-age z-score differences compared with no intervention: 0.06, 95% CI: -0.29, 0.40, and 0.00, 95% CI: -0.35, 0.35, respectively). There were also no effects of the interventions on weight, diarrhea prevalence, or enteric infections. Despite their effectiveness in treating drinking water, the use of the silver-impregnated ceramic water filters and tablets did not reduce enteric infections or improve child growth. More transformative water, sanitation, and hygiene interventions that better prevent enteric infections are likely needed to improve long-term child growth outcomes.

An optimal control problem for carrier dependent diseases.

In developing countries, several diseases spread in human population due to the abundance of houseflies (a kind of carrier). The main reason behind the spread of these diseases is the lack of awareness among peoples regarding the sanitation practices and economic constraints. To understand the dynamics of the spread and control of these diseases, in this paper, we propose a mathematical model by considering logistic growth of houseflies. In the model formulation, it is assumed that houseflies transport the bacteria responsible for the disease transmission from the environment to the edibles of human population. To reduce the density of houseflies and number of infected individuals, an optimization problem is also formulated and analyzed. Numerical simulations are performed to support analytically obtained results.

Barriers and Enabling Factors Associated with the Implementation of Household Solar Water Disinfection: A Qualitative Study in Northwest Ethiopia.

Household water treatment including solar disinfection (SODIS) is recognized worldwide as an important intervention for prevention and control of diarrheal and other waterborne diseases. However, in Ethiopia's countryside, SODIS is not being practiced. Therefore, the objective of this qualitative study conducted in villages of Dabat district in northwest Ethiopia was to explore barriers to and enabling factors for consistent and wider implementation of SODIS. This phenomenological study design included four focus group discussions with 25 parents of children younger than 5 years and interviews with four key informants to elicit their experiences and opinions. ATLAS.ti 8.0 software (GmbH, Berlin, Germany) was used for data organization, and the content was analyzed thematically. Enabling factors were categorized into four themes, such as supportive values for SODIS (positive attitude, advantage of SODIS, and cultural acceptance of SODIS), consistent use of SODIS (community's interest, health education, availability of bright sunlight, and simplicity of the method), participation of family and community in daily implementation of the SODIS process (controlling theft of bottles and recognizing the importance of SODIS technology), and willingness to pay for new polyethylene terephthalate (PET) bottles. On the other hand, barriers were grouped into three themes such as sociocultural (poor knowledge, hesitation to leave SODIS bottles unguarded outdoor, less attention, and unplanned social events), environmental (cloud, shadow over SODIS bottles, turbidity and leeches in source water, and geographical settings), and behavioral (mishandling of SODIS bottles and drinking water). The analysis of the data revealed that all the participants had positive attitude toward the implementation of SODIS, and it was culturally accepted. They identified the barriers to and enabling factors for the implementation of SODIS. Promoting enabling factors and mitigating barriers are substantially important for consistent implementation of SODIS as a long-term interventional measure widely in rural Ethiopia for the achievement of the goal of safe drinking water for all.

Relatório de Avaliação Rápida da Situação de Saúde -Moçambique: Implementação piloto do novo quadro da OMS para apoiar o Desenvolvimento de Estratégias de Saúde Pública na Mineração Artesanal e de Pequena Escala de Ouro no Contexto da Convenção de Minamata sobre Mercúrio / Rapid Health Situation Assessment Report -Mozambique: Pilot Implementation of the New WHO Framework to Support the Development of Public Health Strategies in Artisanal and Small-Scale Gold Mining in the Context of the Minamata Convention on Mercury

A Mineração Artesanal e de Pequena Escala de Ouro (MAPEO) é, em termos gerais, a exploração de pequenos depósitos de ouro por indivíduos, pequenos grupos ou pequenas cooperativas (1). A MAPEO é, geralmente, um trabalho intensivo com nenhuma ou limitada mecanização, e pode ter baixos índices de recuperação. O sector é geralmente caracterizado por baixos níveis de capital, produtividade, segurança ocupacional e acesso limitado aos mercados de terra e comércio. A MAPEO é praticada em mais de 70 países em todo o mundo. Estima-se que 10-15 milhões de pessoas estejam envolvidas na MAPEO, incluindo 4-5 milhões de mulheres e 1 milhão de crianças, enquanto outros 80 a 100 milhões de meios de subsistência de pessoas estão afectados pela MAPEO (2, 3). A MAPEO é uma actividade importante em muitos países em desenvolvimento, uma vez que representa uma fonte primária e adicional de renda, particularmente em regiões rurais onde as alternativas económicas à agricultura são limitadas. Estima-se que o sector de MAPEO contribua com cerca de 25% da produção global de ouro (2)

Investigation of potential pathogenicity of Willaertia magna by investigating the transfer of bacteria pathogenicity genes into its genome.

Willaertia magna c2c maky is a thermophilic amoeba closely related to the genus Naegleria. This free-living amoeba has the ability to eliminate Legionella pneumophila, which is an amoeba-resisting bacterium living in an aquatic environment. To prevent the proliferation of L. pneumophila in cooling towers, the use of W. magna as natural biocide has been proposed. To provide a better understanding of the W. magna genome, whole-genome sequencing was performed through the study of virulence factors and lateral gene transfers. This amoeba harbors a genome of 36.5 megabases with 18,519 predicted genes. BLASTp analyses reported protein homology between 136 W. magna sequences and amoeba-resistant microorganisms. Horizontal gene transfers were observed based on the basis of the phylogenetic reconstruction hypothesis. We detected 15 homologs of N. fowleri genes related to virulence, although these latter were also found in the genome of N. gruberi, which is a non-pathogenic amoeba. Furthermore, the cytotoxicity test performed on human cells supports the hypothesis that the strain c2c maky is a non-pathogenic amoeba. This work explores the genomic repertory for the first draft genome of genus Willaertia and provides genomic data for further comparative studies on virulence of related pathogenic amoeba, N. fowleri.

Linking Decision Theory and Quantitative Microbial Risk Assessment: Tradeoffs Between Compliance and Efficacy for Waterborne Disease Interventions.

Achieving health gains from the U.N. Sustainable Development Goals of universal coverage for water and sanitation will require interventions that can be widely adopted and maintained. Effectiveness-how an intervention performs based on actual use-as opposed to efficacy will therefore be central to evaluations of new and existing interventions. Incomplete compliance-when people do not always use the intervention and are therefore exposed to contamination-is thought to be responsible for the lower-than-expected risk reductions observed from water, sanitation, and hygiene interventions based on their efficacy at removing pathogens. We explicitly incorporated decision theory into a quantitative microbial risk assessment model. Specifically, we assume that the usability of household water treatment (HWT) devices (filters and chlorine) decreases as they become more efficacious due to issues such as taste or flow rates. Simulations were run to examine the tradeoff between device efficacy and usability. For most situations, HWT interventions that trade lower efficacy (i.e., remove less pathogens) for higher compliance (i.e., better usability) contribute substantial reductions in diarrheal disease risk compared to devices meeting current World Health Organization efficacy guidelines. Recommendations that take into account both the behavioral and microbiological properties of treatment devices are likely to be more effective at reducing the burden of diarrheal disease than current standards that only consider efficacy.

Reservoir Chlorination of the Local Well-Tank-Faucet Systems is a Rapid and Efficient Tool for Controlling Water-related Diseases: Pathogens' Load-clinical Response Rate Correlation.

Chlorination is a chemical method for water disinfection that has been proved to be highly effective in controlling waterborne diarrheal diseases. Most studies have focused on wells' chlorination or later at household level, whereas there have been relatively few researches evaluating the treatment of reservoirs water. Our study followed a mixed design with a before-and-after comparison. It was conducted in a refugee settlement, Um-Baddah Nevachah, which is located in the western outskirts of Khartoum, Sudan. Baseline total coliform test findings have paired areas of four wells that were labeled as sample or control based on fair coin-tossing. A centrally administered water treatment that contains chlorine was added to intervention wells, whereas the other set was considered as chlorine-free placebo. Data were collected 15 days later from the following four main sources: total coliform count, questionnaire-based experimental data trackers, health center records, and face-to-face interviews. The calculated sample size was 341 with corresponding controls selected by systematic random sampling. We found that both groups' prevalences of waterborne diseases were significantly different before the intervention and they shifted later (p = 0.043 vs. p = 0.496, 95% CI). These findings suggest that reservoir chlorination provides prompt disinfection of well-tank-faucet systems water. Highly credible gastroenteritis is a useful tool to detect cases of gastroenteritis in resources limit settings.

Water uses, treatment, and sanitation practices in rural areas of Chandigarh and its relation with waterborne diseases.

Availability of clean water and adequate sanitation facilities are the principal measures for limiting various waterborne diseases. These basic amenities are critical for health and sustainable socio-economic development. This study attempted to assess the status of water and sanitation facilities and practices of the people living in rural areas of Chandigarh including awareness about the waterborne diseases. The community-based cross-sectional study design was adopted having 300 households across 12 villages of city Chandigarh. A standardized interview schedule was used to collect information related to water uses, storage, water treatment options, water conservation practices, personal hygiene, knowledge about waterborne diseases, and government schemes. The interview schedule was administered with the head of the family as a study approach during the door-to-door survey. Households in rural Chandigarh have municipal water supply for drinking as well as other domestic purposes. The mean per capita water usage was 67 ± 13.4 l. Most (68.6%) of the study participants reported that they do not treat water before drinking and store it in plastic bottles or bucket (58%). The survey shows that 97% of the household had functional toilets in their premises, remaining reported lack of finances, and space for construction as major barriers. Regarding personal hygiene, 83% of respondents wash hands with soap and rest used only water or ash. Observations made under the study highlighted the need to create awareness regarding the role of water and sanitation practices on health including knowledge about various government schemes to improve water quality, sanitation, and hygiene practices for better health.