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Kering K, Wang Y, Mbae C, Mugo M, Ongadi B, Odityo G, Muturi P, Yakubu H, Liu P, Durry S, Deshpande A, Gebreyes W, Moe C, Kariuki S. Pathways of exposure to Vibrio Cholerae in an urban informal settlement in Nairobi, Kenya. PLOS GLOBAL PUBLIC HEALTH 2024; 4:e0002880. [PMID: 39163285 PMCID: PMC11335117 DOI: 10.1371/journal.pgph.0002880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 07/31/2024] [Indexed: 08/22/2024]
Abstract
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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Affiliation(s)
- Kelvin Kering
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Yuke Wang
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Cecilia Mbae
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Michael Mugo
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Beatrice Ongadi
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Georgina Odityo
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Peter Muturi
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Habib Yakubu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Pengbo Liu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Sarah Durry
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Aniruddha Deshpande
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Wondwossen Gebreyes
- Global One Health initiative (GOHi), The Ohio State University, Columbus, Ohio, United States of America
- Veterinary Preventive Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Christine Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
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2
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Sprouse L, Lebu S, Nguyen J, Muoghalu C, Uwase A, Guo J, Baldwin-SoRelle C, Anthonj C, Simiyu SN, Akudago JA, Manga M. Shared sanitation in informal settlements: A systematic review and meta-analysis of prevalence, preferences, and quality. Int J Hyg Environ Health 2024; 260:114392. [PMID: 38788338 DOI: 10.1016/j.ijheh.2024.114392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 05/03/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024]
Abstract
Shared sanitation facilities are not considered a type of basic sanitation by the WHO/UNICEF Joint Monitoring Programme (JMP), though they may be the only alternative to open defecation in urban informal settlements. Additionally, JMP indicators for sanitation do not cover aspects related to the quality of shared sanitation, such as those outlined in the Human Right to Water and Sanitation (HRTWS) framework. Data on the prevalence of shared sanitation within informal settlement areas is limited, and there is a need to understand user preferences, experiences, and barriers to the use of shared sanitation to inform effective policy and practice. This systematic review aims to summarize the prevalence and number of households sharing sanitation in informal settlements globally, as well as user experiences and barriers to successful implementation of shared sanitation. We included studies available in English and published after January 1, 2000. We retrieved 4741 articles from seven databases and included a total of 167 relevant publications. Among included studies, 54 reported the prevalence of shared sanitation in informal settlements, and 138 studies reported on user perceptions and experiences related to shared sanitation quality. A meta-analysis of studies reporting the prevalence of shared sanitation in informal settlements globally revealed an estimated overall prevalence of 67% [95% CI: 61%-73%]. Commonly reported user preferences included cleanliness to promote continued use of shared facilities, privacy with a lockable door, facilities for menstrual hygiene management, safety and protection against violence, 24/7 access, proper lighting, and shared responsibility for facility management - which align with the HRTWS framework and represent barriers to shared sanitation use. Based on the findings of this review, we recommend including the number of households or people sharing a sanitation facility in monitoring of shared sanitation quality, locating sanitation facilities within compounds, where applicable, and promoting safety, dignity, and privacy of all users in the development of shared sanitation quality indicators.
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Affiliation(s)
- Lauren Sprouse
- Department of Environmental Sciences and Engineering, The University of North Carolina at Chapel Hill, 4114 McGavran Greenberg Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
| | - Sarah Lebu
- Department of Environmental Sciences and Engineering, The University of North Carolina at Chapel Hill, 4114 McGavran Greenberg Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
| | - Jackqueline Nguyen
- Department of Environmental Sciences and Engineering, The University of North Carolina at Chapel Hill, 4114 McGavran Greenberg Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
| | - Chimdi Muoghalu
- Department of Environmental Sciences and Engineering, The University of North Carolina at Chapel Hill, 4114 McGavran Greenberg Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
| | - Andromede Uwase
- Department of Environmental Sciences and Engineering, The University of North Carolina at Chapel Hill, 4114 McGavran Greenberg Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
| | - Jiahui Guo
- Department of Environmental Sciences and Engineering, The University of North Carolina at Chapel Hill, 4114 McGavran Greenberg Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
| | | | - Carmen Anthonj
- Faculty of Geo-Information Science and Earth Observation, ITC, University of Twente, Enschede, the Netherlands
| | - Sheillah N Simiyu
- African Population and Health Research Center, Manga Close, Off Kirawa Road, P.O Box 10787-00100, Nairobi, Kenya
| | - John Apambilla Akudago
- Global Programs, Habitat for Humanity International, 1202 Aspen Meadows Dr NE, Rio Rancho, NM, 87144, USA
| | - Musa Manga
- Department of Environmental Sciences and Engineering, The University of North Carolina at Chapel Hill, 4114 McGavran Greenberg Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA; Department of Construction Economics and Management, College of Engineering, Design, Art and Technology (CEDAT), Makerere University, P.O. Box 7062, Kampala, Uganda.
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3
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Amin N, Foster T, Shimki NT, Willetts J. Hospital wastewater (HWW) treatment in low- and middle-income countries: A systematic review of microbial treatment efficacy. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:170994. [PMID: 38365018 DOI: 10.1016/j.scitotenv.2024.170994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 02/13/2024] [Accepted: 02/13/2024] [Indexed: 02/18/2024]
Abstract
BACKGROUND Proper treatment of hospital wastewater (HWW) is crucial to minimize the long-term effects on human health and aquatic ecosystems. However, the majority of HWW generated in low and middle-income countries (LMICs), is discharged without adequate treatment. This systematic review aims to fill the knowledge gap in LMICs by examining the efficacy of HWW treatment and the types of technologies used. METHODS Studies included in the review offered valuable insights into the current state of HWW management in LMICs. Between 2000 and 2022, only 36 research studies focused on hospital-based wastewater treatment within LMICs. Data were extracted on wastewater treatment technologies in hospitals or healthcare settings in LMICs. Data on sampling techniques, effectiveness, microorganisms and risk of bias of included studies were recorded. RESULTS A total of 36 articles met the eligibility criteria: mentioned about 1) hospitals 2) wastewater treatment 3) LMICs and 4) treatment efficacy. Twenty-two studies were conducted in Asia (22/36), 17 were conducted in countries with high Human Development Index. Constructed wetland, and activated sludge process were the most common technologies used in LMICs. A few studies utilized membrane bioreactors and ozone/UV treatment. Fourteen studies reported the concentration reduction to assess the microbial efficacy of the treatment process, 29/36 studies did not meet the national standards for effluent discharge. Reporting on sampling methods, wastewater treatment processes and efficacy of HWW treatment were at high risk of bias. Extreme heterogeneity in study methods and outcomes reporting precluded meta-analysis. CONCLUSIONS The existing evidence indicates inadequate microbial treatment in low- and middle-income country hospitals, with this systematic review emphasizing the need for improvement in healthcare waste management. It underscores the importance of long-term studies using innovative treatment methods to better understand waste removal in LMIC hospitals and calls for further research to develop context-specific healthcare waste treatment approaches in these regions.
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Affiliation(s)
- Nuhu Amin
- Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW 2007, Australia; Environmental Health and WASH, Health System and Population Studies Division, icddr,b, Dhaka, Bangladesh.
| | - Tim Foster
- Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW 2007, Australia
| | - Nafeya Tabassum Shimki
- Environmental Health and WASH, Health System and Population Studies Division, icddr,b, Dhaka, Bangladesh
| | - Juliet Willetts
- Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW 2007, Australia
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Gwenzi W, Adelodun B, Kumar P, Ajibade FO, Silva LFO, Choi KS, Selvarajan R, Abia ALK, Gholipour S, Mohammadi F, Nikaeen M. Human viral pathogens in the wastewater-source water-drinking water continuum: Evidence, health risks, and lessons for future outbreaks in low-income settings. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170214. [PMID: 38278242 DOI: 10.1016/j.scitotenv.2024.170214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 01/10/2024] [Accepted: 01/14/2024] [Indexed: 01/28/2024]
Abstract
Human viral pathogens, including SARS-CoV-2 continue to attract public and research attention due to their disruption of society, global health, and the economy. Several earlier reviews have investigated the occurrence and fate of SARS-CoV-2 in wastewater, and the potential to use such data in wastewater-based epidemiology. However, comprehensive reviews tracking SARS-CoV-2 and other viral pathogens in the wastewater-water-drinking water continuum and the associated risk assessment are still lacking. Therefore, to address this gap, the present paper makes the following contributions: (1) critically examines the early empirical results to highlight the occurrence and stability of SARS-CoV-2 in the wastewater-source water-drinking water continuum, (2) discusses the anthropogenic and hydro(geo)logical processes controlling the circulation of SARS-CoV-2 in the wastewater-source water-drinking water continuum, (3) discusses the risky behaviour, drivers and high-risk settings in the wastewater-source water-drinking water continuum, (4) uses the available empirical data on SARS-CoV-2 occurrence in the wastewater-source water-drinking water continuum to discuss human health risks from multiple exposure pathways, gendered aspects of SARS-CoV-2 transmission via shared on-site sanitation systems, and (5) develops and risk mitigation strategy based on the available empirical evidence and quantitative human risk assessment data. Finally, it presents a comprehensive research agenda on SARS-CoV-2/COVID-19 to guide the mitigation of future similar outbreaks in low-income settings.
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Affiliation(s)
- Willis Gwenzi
- Biosystems and Environmental Engineering Research Group, 380 New Adylin, Westgate, Harare, Zimbabwe; Currently Alexander von Humboldt Fellow and Guest/Visiting Professor at: Grassland Science and Renewable Plant Resources, Faculty of Organic Agricultural Sciences, Universität Kassel, Steinstraße 19, D-37213 Witzenhausen, Germany; Leibniz-Institut für Agrartechnik und Bioökonomie e.V. (ATB), Max-Eyth-Allee 100, D-14469, Potsdam, Germany.
| | - Bashir Adelodun
- Department of Agricultural Civil Engineering, Kyungpook National University, Daegu 41566, Republic of Korea; Department of Agricultural and Biosystems Engineering, University of Ilorin, PMB 1515, Ilorin 240003, Nigeria; Institute of Agricultural Science & Technology, Kyungpook National University, Daegu 41566, Republic of Korea.
| | - Pankaj Kumar
- Agro-Ecology and Pollution Research Laboratory, Department of Zoology and Environmental Science, Gurukula Kangri (Deemed to Be University), Haridwar 249404, India; Research and Development Division, Society for AgroEnvironmental Sustainability, Dehradun 248007, India.
| | - Fidelis Odedishemi Ajibade
- Department of Civil and Environmental Engineering, Federal University of Technology, PMB 704, Akure, 340001, Nigeria.
| | - Luis F O Silva
- Department of Civil and Environmental Engineering, Universidad de la Costa, Calle 58 #55-66, 080002 Barranquilla, Atlàntico, Colombia.
| | - Kyung Sook Choi
- Department of Agricultural Civil Engineering, Kyungpook National University, Daegu 41566, Republic of Korea; Institute of Agricultural Science & Technology, Kyungpook National University, Daegu 41566, Republic of Korea.
| | - Ramganesh Selvarajan
- Department of Environmental Sciences, College of Agricultural and Environmental Sciences, University of South Africa, Florida branch, Johannesburg, South Africa
| | - Akebe Luther King Abia
- Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa; Environmental Research Foundation, Westville 3630, Kwazulu-Natal, South Africa
| | - Sahar Gholipour
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Farzaneh Mohammadi
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahnaz Nikaeen
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
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5
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Strande L, Evans B, von Sperling M, Bartram J, Harada H, Nakagiri A, Nguyen VA. Urban Sanitation: New Terminology for Globally Relevant Solutions? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:15771-15779. [PMID: 37819045 PMCID: PMC10603773 DOI: 10.1021/acs.est.3c04431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Indexed: 10/13/2023]
Abstract
Progress toward Sustainable Development Goals for global access to safe sanitation is lagging significantly. In this Feature, we propose that misleading terminology leads to errors of categorization and hinders progress toward sanitation service provision in urban areas. Binary classifications such as "offsite/onsite" and "sewered/nonsewered" do not capture the need for "transport to treatment" or the complexity of urban sanitation and should be discarded. "Fecal sludge management" is used only in the development context of low- or middle-income countries, implying separate solutions for "poor" or "southern" contexts, which is unhelpful. Terminology alone does not solve problems, but rather than using outdated or "special" terminology, we argue that a robust terminology that is globally relevant across low-, middle-, and upper-income contexts is required to overcome increasingly unhelpful assumptions and stereotypes. The use of accurate, technically robust vocabulary and definitions can improve decisions about management and selection of treatment, promote a circular economy, provide a basis for evidence-based science and technology research, and lead to critical shifts and transformations to set policy goals around truly safely managed sanitation. In this Feature, the three current modes of sanitation are defined, examples of misconceptions based on existing terminology are presented, and a new terminology for collection and conveyance is proposed: (I) fully road transported, (II) source-separated mixed transport, (III) mixed transport, and (IV) fully pipe transported.
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Affiliation(s)
- Linda Strande
- Eawag:
Swiss Federal Institute of Aquatic Science and Technology, Department of Sanitation, Water and Solid Waste for
Development (Sandec), Überlandstrasse 133, Dübendorf 8600, Switzerland
| | - Barbara Evans
- School
of Civil Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, U.K.
| | - Marcos von Sperling
- Department
of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627 - Campus Pampulha, Belo Horizonte 31270-901, Brazil
| | - Jamie Bartram
- School
of Civil Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, U.K.
| | - Hidenori Harada
- Graduate
School of Asian and African Area Studies, Kyoto University, Yoshida-shimoadachi-cho 46, Sakyo, Kyoto 606-8501, Japan
| | - Anne Nakagiri
- Department
of Civil and Environmental Engineering, Kyambogo University, Kyambogo Road, Kampala, P.O. Box 1, Kyambogo, Uganda
| | - Viet-Anh Nguyen
- Institute
of Environmental Science and Engineering (IESE), Hanoi University of Civil Engineering (HUCE), 55 Giai Phong Road, Hanoi 113068, Vietnam
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Espira LM, Gessese B, Kassa BA, Wu CC, Riley J, Bedru S, Sahilu G, Desta A, Baye K, Jones AD, Love NG, Eisenberg JNS. Multiscalar Evaluation of the Water Distribution System and Diarrheal Disease Risk in Addis Ababa, Ethiopia. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13313-13324. [PMID: 37642551 PMCID: PMC10501120 DOI: 10.1021/acs.est.2c08976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 07/22/2023] [Accepted: 07/24/2023] [Indexed: 08/31/2023]
Abstract
Despite growing urbanization, our understanding of the impacts of water and sanitation on human health has largely come from studies in rural sectors. To this end, we collected data at both regional (water quality measures from water treatment systems) and community (cross-sectional surveys) scales to examine determinants of enteric pathogen infection and diarrheal disease among infants in Addis Ababa, Ethiopia. Regionally, the Legedadi water treatment plant had significantly lower heterotrophic plate counts, total coliform counts, and fecal coliform counts compared with the Gefersa water treatment plant. The number of pathogen types in infant stool also differed by plant. Decreases in chlorine levels and increases in the relative abundance of Gammaproteobacteria with distance from treatment plants suggest a compromised water distribution system. In communities, infants in households that obtained water from yard pipes or public taps had significantly lower odds of diarrhea compared to households that had water piped into their dwellings (OR = 0.35, 95% CI 0.16, 0.76, and OR = 0.39, 95% CI 0.15, 1.00, respectively). Similarly, infants in households that boiled or filtered water had significantly lower odds of diarrhea compared to households that did not treat water (OR = 0.40, 95% CI 0.19, 0.86 and OR = 0.23, 95% CI 0.06, 0.84, respectively). Integrating multiscalar data better informs the health impacts of water in urban settings.
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Affiliation(s)
- Leon M. Espira
- Department
of Epidemiology, University of Michigan
School of Public Health, Ann Arbor, Michigan 48109, United States
| | - Brook Gessese
- Ethiopian
Institute of Water Resources, Addis Ababa
University, Addis
Ababa 150461, Ethiopia
| | - Bayable A. Kassa
- Institute
of Biotechnology, Addis Ababa University, Addis Ababa 1176, Ethiopia
| | - Chia-Chen Wu
- Institute
of Environmental Engineering, National Yang
Ming Chiao Tung University, Hsinchu City 30010, Taiwan
| | - Joshua Riley
- Department
of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Seifedin Bedru
- School of
Civil and Environmental Engineering, Addis
Ababa University, Addis Ababa 1176, Ethiopia
| | - Geremew Sahilu
- School of
Civil and Environmental Engineering, Addis
Ababa University, Addis Ababa 1176, Ethiopia
| | - Adey Desta
- Department
of Microbial and Cellular Biology, Addis
Ababa University, Addis Ababa 1176, Ethiopia
| | - Kaleab Baye
- Center
for
Food Science and Nutrition, College of Natural and Computational Sciences, Addis Ababa University, Addis Ababa 1176, Ethiopia
| | - Andrew D. Jones
- Department
of Nutritional Sciences, University of Michigan
School of Public Health, Ann Arbor, Michigan 48109, United States
| | - Nancy G. Love
- Department
of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Joseph N. S. Eisenberg
- Department
of Epidemiology, University of Michigan
School of Public Health, Ann Arbor, Michigan 48109, United States
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Adhikari S, Hunter E, Vossenberg JVD, Thomas J. A review of latrine front-end characteristics associated with microbial infection risk; reveals a lack of pathogen density data. Int J Hyg Environ Health 2023; 254:114261. [PMID: 37734133 DOI: 10.1016/j.ijheh.2023.114261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/06/2023] [Accepted: 09/09/2023] [Indexed: 09/23/2023]
Abstract
Unsafe sanitation accounts for an estimated 898,000 global deaths annually. The faecal pathogen transmission pathway is complex with several possible routes. Latrine front-end characteristics and usage behaviours are one key transmission pathway for microbial pathogens, however, there has not yet been a synthesis of the available research. This review aims to compare the microbial infection risks with latrine front-end components including any quantified microbial densities within the household latrines. This review was conducted with no restriction on the geographical location of the research. Of 118 studies reviewed, only ten (8%) have quantified the microbial density inside the household latrines compared to 109 (92%) measuring the infection risks. The reported risks were most frequent for specific bacterial (n = 34), and helminths infections (n = 32) compared to diarrhoea (n = 23), combined (n = 15), protozoan (n = 4), and viral (n = 4) infections. The infections risk decreased for using latrines lying at a higher position on the sanitation ladder (for example flush latrines) compared to those lying lower (for example pit latrines). The trend was similar for using floor materials that were easier to clean and less favourable for pathogen survival inside the latrines (for example, concrete as opposed to earth). Faecal coliforms were reported highest on the surface of the squat pan (743 CFU/cm2) of pour-flush latrines and helminths on earth floors of pit latrines (1.5 eggs and larvae per gram of soil). Irrespective of latrine type and its position on the sanitation ladder, a dirty latrine, evidenced by a visible lack of cleanliness, significantly increased the risk for all infections. This study recommends that effective microbial infection risk reduction in latrines can be gained efficiently by ensuring washable surfaces and consistent cleaning practices. Future studies should include more rigorous measurements of microbial densities in various latrine types incorporating the different front-end components and usage behaviours.
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Affiliation(s)
- Sabita Adhikari
- School of Civil Engineering, The University of Sydney, Australia.
| | - Erin Hunter
- Department of Public Health Sciences, College of Behavioural, Social and Health Sciences, Clemson University, United States.
| | - Jack van de Vossenberg
- Water Supply, Sanitation and Environmental Engineering Department, IHE Delft Institute of Water Education, the Netherlands.
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8
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Bilal H, Li X, Iqbal MS, Mu Y, Tulcan RXS, Ghufran MA. Surface water quality, public health, and ecological risks in Bangladesh-a systematic review and meta-analysis over the last two decades. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:91710-91728. [PMID: 37526829 DOI: 10.1007/s11356-023-28879-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 07/16/2023] [Indexed: 08/02/2023]
Abstract
Water quality has recently emerged as one of the utmost severe ecological problems being faced by the developing countries all over the world, and Bangladesh is no exception. Both surface and groundwater sources contain different contaminants, which lead to numerous deaths due to water-borne diseases, particularly among children. This study presents one of the most comprehensive reviews on the current status of water quality in Bangladesh with a special emphasis on both conventional pollutants and emerging contaminants. Data show that urban rivers in Bangladesh are in a critical condition, especially Korotoa, Teesta, Rupsha, Pashur, and Padma. The Buriganga River and few locations in the Turag, Balu, Sitalakhya, and Karnaphuli rivers have dissolvable oxygen (DO) levels of almost zero. Many waterways contain traces of NO3, NO2, and PO4-3 pollutants. The majority of the rivers in Bangladesh also have Zn, Cu, Fe, Pb, Cd, Ni, Mn, As, and Cr concentrations that exceed the WHO permissible limits for safe drinking water, while their metal concentrations exceed the safety threshold for irrigation. Mercury poses the greatest hazard with 90.91% of the samples falling into the highest risk category. Mercury is followed by zinc 57.53% and copper 29.16% in terms of the dangers they pose to public health and the ecosystem. Results show that a considerable percentage of the population is at risk, being exposed to contaminated water. Despite hundreds of cryptosporidiosis cases reported, fecal contamination, i.e., Cryptosporidium, is totally ignored and need serious considerations to be regularly monitored in source water.
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Affiliation(s)
- Hazrat Bilal
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing, 100875, China
| | - Xiaowen Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing, 100875, China.
| | | | - Yonglin Mu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing, 100875, China
| | - Roberto Xavier Supe Tulcan
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing, 100875, China
| | - Muhammad Asad Ghufran
- Department of Environmental Science, International Islamic University, Islamabad, Pakistan
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9
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Amin N, Haque R, Rahman MZ, Rahman MZ, Mahmud ZH, Hasan R, Islam MT, Sarker P, Sarker S, Adnan SD, Akter N, Johnston D, Rahman M, Liu P, Wang Y, Shirin T, Rahman M, Bhattacharya P. Dependency of sanitation infrastructure on the discharge of faecal coliform and SARS-CoV-2 viral RNA in wastewater from COVID and non-COVID hospitals in Dhaka, Bangladesh. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 867:161424. [PMID: 36623655 PMCID: PMC9822545 DOI: 10.1016/j.scitotenv.2023.161424] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/31/2022] [Accepted: 01/02/2023] [Indexed: 05/25/2023]
Abstract
The detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA in wastewater can be used as an indicator of the presence of SARS-CoV-2 infection in specific catchment areas. We conducted a hospital-based study to explore wastewater management in healthcare facilities and analyzed SARS-CoV-2 RNA in the hospital wastewater in Dhaka city during the Coronavirus disease (COVID-19) outbreak between September 2020-January 2021. We selected three COVID-hospitals, two non-COVID-hospitals, and one non-COVID-hospital with COVID wards, conducted spot-checks of the sanitation systems (i.e., toilets, drainage, and septic-tank), and collected 90 untreated wastewater effluent samples (68 from COVID and 22 from non-COVID hospitals). E. coli was detected using a membrane filtration technique and reported as colony forming unit (CFU). SARS-CoV-2 RNA was detected using the iTaq Universal Probes One-Step kit for RT-qPCR amplification of the SARS-CoV-2 ORF1ab and N gene targets and quantified for SARS-CoV-2 genome equivalent copies (GEC) per mL of sample. None of the six hospitals had a primary wastewater treatment facility; two COVID hospitals had functional septic tanks, and the rest of the hospitals had either broken onsite systems or no containment of wastewater. Overall, 100 % of wastewater samples were positive with a high concentration of E. coli (mean = 7.0 log10 CFU/100 mL). Overall, 67 % (60/90) samples were positive for SARS-CoV-2. The highest SARS-CoV-2 concentrations (median: 141 GEC/mL; range: 13-18,214) were detected in wastewater from COVID-hospitals, and in non-COVID-hospitals, the median SARS-CoV-2 concentration was 108 GEC/mL (range: 30-1829). Our results indicate that high concentrations of E. coli and SARS-CoV-2 were discharged through the hospital wastewater (both COVID and non-COVID) without treatment into the ambient water bodies. Although there is no evidence for transmission of SARS-CoV-2 via wastewater, this study highlights the significant risk posed by wastewater from health care facilities in Dhaka for the many other diseases that are spread via faecal oral route. Hospitals in low-income settings could function as sentinel sites to monitor outbreaks through wastewater-based epidemiological surveillance systems. Hospitals should aim to adopt the appropriate wastewater treatment technologies to reduce the discharge of pathogens into the environment and mitigate environmental exposures.
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Affiliation(s)
- Nuhu Amin
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh; Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW, 2007, Australia.
| | - Rehnuma Haque
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh; School of Medicine, Stanford University, Stanford, CA, USA
| | - Md Ziaur Rahman
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Mohammed Ziaur Rahman
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Zahid Hayat Mahmud
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Rezaul Hasan
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Md Tahmidul Islam
- COVID-19 Research@KTH, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, SE 114 28 Stockholm, Sweden; WaterAid, Bangladesh
| | - Protim Sarker
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Supriya Sarker
- Directorate General of Health Services (DGHS), Bangladesh
| | | | - Nargis Akter
- Water, Sanitation & Hygiene (WASH) section, UNICEF, Bangladesh
| | - Dara Johnston
- Water, Sanitation & Hygiene (WASH) section, UNICEF, Bangladesh
| | - Mahbubur Rahman
- Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh
| | - Pengbo Liu
- Center for Global Safe Water, Sanitation, and Hygiene, Emory University, Atlanta, GA, USA
| | - Yuke Wang
- Center for Global Safe Water, Sanitation, and Hygiene, Emory University, Atlanta, GA, USA
| | - Tahmina Shirin
- Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh
| | - Mahbubur Rahman
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Prosun Bhattacharya
- COVID-19 Research@KTH, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, SE 114 28 Stockholm, Sweden
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10
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Mertens A, Arnold BF, Benjamin-Chung J, Boehm AB, Brown J, Capone D, Clasen T, Fuhrmeister E, Grembi JA, Holcomb D, Knee J, Kwong LH, Lin A, Luby SP, Nala R, Nelson K, Njenga SM, Null C, Pickering AJ, Rahman M, Reese HE, Steinbaum L, Stewart J, Thilakaratne R, Cumming O, Colford JM, Ercumen A. Effects of water, sanitation, and hygiene interventions on detection of enteropathogens and host-specific faecal markers in the environment: a systematic review and individual participant data meta-analysis. Lancet Planet Health 2023; 7:e197-e208. [PMID: 36889861 PMCID: PMC10009758 DOI: 10.1016/s2542-5196(23)00028-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 01/25/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Water, sanitation, and hygiene (WASH) improvements are promoted to reduce diarrhoea in low-income countries. However, trials from the past 5 years have found mixed effects of household-level and community-level WASH interventions on child health. Measuring pathogens and host-specific faecal markers in the environment can help investigate causal pathways between WASH and health by quantifying whether and by how much interventions reduce environmental exposure to enteric pathogens and faecal contamination from human and different animal sources. We aimed to assess the effects of WASH interventions on enteropathogens and microbial source tracking (MST) markers in environmental samples. METHODS We did a systematic review and individual participant data meta-analysis, which included searches from Jan 1, 2000, to Jan 5, 2023, from PubMed, Embase, CAB Direct Global Health, Agricultural and Environmental Science Database, Web of Science, and Scopus, of prospective studies with water, sanitation, or hygiene interventions and concurrent control group that measured pathogens or MST markers in environmental samples and measured child anthropometry, diarrhoea, or pathogen-specific infections. We used covariate-adjusted regression models with robust standard errors to estimate study-specific intervention effects and pooled effect estimates across studies using random-effects models. FINDINGS Few trials have measured the effect of sanitation interventions on pathogens and MST markers in the environment and they mostly focused on onsite sanitation. We extracted individual participant data on nine environmental assessments from five eligible trials. Environmental sampling included drinking water, hand rinses, soil, and flies. Interventions were consistently associated with reduced pathogen detection in the environment but effect estimates in most individual studies could not be distinguished from chance. Pooled across studies, we found a small reduction in the prevalence of any pathogen in any sample type (pooled prevalence ratio [PR] 0·94 [95% CI 0·90-0·99]). Interventions had no effect on the prevalence of MST markers from humans (pooled PR 1·00 [95% CI 0·88-1·13]) or animals (pooled PR 1·00 [95% CI 0·97-1·03]). INTERPRETATION The small effect of these sanitation interventions on pathogen detection and absence of effects on human or animal faecal markers are consistent with the small or null health effects previously reported in these trials. Our findings suggest that the basic sanitation interventions implemented in these studies did not contain human waste and did not adequately reduce exposure to enteropathogens in the environment. FUNDING Bill and Melinda Gates Foundation and the UK Foreign and Commonwealth Development Office.
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Affiliation(s)
- Andrew Mertens
- Division of Epidemiology and Biostatistics, University of California, Berkeley, CA, USA.
| | - Benjamin F Arnold
- Francis I Proctor Foundation and Department of Ophthalmology, University of California, San Francisco, CA, USA
| | - Jade Benjamin-Chung
- Department of Epidemiology and Population Health, Stanford University, Stanford, CA, USA
| | - Alexandria B Boehm
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA
| | - Joe Brown
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, Michael Hooker Research Center, University of North Carolina, Chapel Hill, NC, USA
| | - Drew Capone
- Department of Environmental and Occupational Health, Indiana University Bloomington, Bloomington, IN, USA
| | - Thomas Clasen
- Department of Environmental Health, Rollins School of Public Health, Emory University, NE, Atlanta, GA, USA
| | - Erica Fuhrmeister
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | | | - David Holcomb
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, Michael Hooker Research Center, University of North Carolina, Chapel Hill, NC, USA
| | - Jackie Knee
- Department of Disease Control, London School of Tropical Medicine & Hygiene, London, UK
| | - Laura H Kwong
- Division of Environmental Health Sciences, University of California, Berkeley, CA, USA
| | - Audrie Lin
- Department of Biobehavioral Health, Pennsylvania State University, PA, USA
| | - Stephen P Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, CA, USA
| | - Rassul Nala
- Ministério da Saúde, Instituto Nacional de Saúde Maputo, Maputo, Mozambique
| | - Kara Nelson
- Department of Civil and Environmental Engineering, College of Engineering, University of California, Berkeley, CA, USA
| | | | | | - Amy J Pickering
- Department of Civil and Environmental Engineering, College of Engineering, University of California, Berkeley, CA, USA
| | - Mahbubur Rahman
- Environmental Interventions Unit, Infectious Diseases Division, Dhaka, Bangladesh
| | - Heather E Reese
- Department of Environmental Health, Rollins School of Public Health, Emory University, NE, Atlanta, GA, USA
| | - Lauren Steinbaum
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Jill Stewart
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, Michael Hooker Research Center, University of North Carolina, Chapel Hill, NC, USA
| | - Ruwan Thilakaratne
- Division of Epidemiology and Biostatistics, University of California, Berkeley, CA, USA
| | - Oliver Cumming
- Department of Disease Control, London School of Tropical Medicine & Hygiene, London, UK
| | - John M Colford
- Division of Epidemiology and Biostatistics, University of California, Berkeley, CA, USA
| | - Ayse Ercumen
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC, USA
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11
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Haque R, Moe CL, Raj SJ, Ong L, Charles K, Ross AG, Shirin T, Raqib R, Sarker P, Rahman M, Rahman MZ, Amin N, Mahmud ZH, Rahman M, Johnston D, Akter N, Khan TA, Hossain MA, Hasan R, Islam MT, Bhattacharya P. Wastewater surveillance of SARS-CoV-2 in Bangladesh: Opportunities and challenges. CURRENT OPINION IN ENVIRONMENTAL SCIENCE & HEALTH 2022; 27:100334. [PMID: 35434440 PMCID: PMC9004539 DOI: 10.1016/j.coesh.2022.100334] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The ongoing pandemic of the coronavirus disease 2019 (COVID-19) is a public health crisis of global concern. The progression of the COVID-19 pandemic has been monitored in the first place by testing symptomatic individuals for SARS-CoV-2 virus in the respiratory samples. Concurrently, wastewater carries feces, urine, and sputum that potentially contains SARS-CoV-2 intact virus or partially damaged viral genetic materials excreted by infected individuals. This brings significant opportunities for understanding the infection dynamics by environmental surveillance. It has advantages for the country, especially in densely populated areas where individual clinical testing is difficult. However, there are several challenges including: 1) establishing a sampling plan and schedule that is representative of the various catchment populations 2) development and validation of standardized protocols for the laboratory analysis 3) understanding hydraulic flows and virus transport in complex wastewater drainage systems and 4) collaborative efforts from government agencies, NGOs, public health units and academia.
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Affiliation(s)
- Rehnuma Haque
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
- School of Medicine, Stanford University, USA
| | - Christine L Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, USA
| | - Suraja J Raj
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, USA
| | - Li Ong
- School of Geography and the Environment, University of Oxford, UK
| | - Katrina Charles
- School of Geography and the Environment, University of Oxford, UK
| | - Allen G Ross
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - Tahmina Shirin
- Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh
| | - Rubhana Raqib
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - Protim Sarker
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - Mahbubur Rahman
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - Mohammed Ziaur Rahman
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - Nuhu Amin
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - Zahid Hayat Mahmud
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - Mahbubur Rahman
- Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh
| | - Dara Johnston
- Water, Sanitation & Hygiene (WASH) Section, UNICEF, Bangladesh
| | - Nargis Akter
- Water, Sanitation & Hygiene (WASH) Section, UNICEF, Bangladesh
| | - Taqsem A Khan
- Dhaka Water Supply & Sewerage Authority (DWASA), Bangladesh
| | | | - Rezaul Hasan
- International Centre for Diarrhoeal Disease Research Bangladesh (ICDDRB), Dhaka, 1212, Bangladesh
| | - M Tahmidul Islam
- COVID-19 Research @KTH, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Prosun Bhattacharya
- COVID-19 Research @KTH, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Stockholm, Sweden
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12
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Manga M, Kolsky P, Rosenboom JW, Ramalingam S, Sriramajayam L, Bartram J, Stewart J. Public health performance of sanitation technologies in Tamil Nadu, India: Initial perspectives based on E. coli release. Int J Hyg Environ Health 2022; 243:113987. [PMID: 35623255 PMCID: PMC9227721 DOI: 10.1016/j.ijheh.2022.113987] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 04/27/2022] [Accepted: 05/11/2022] [Indexed: 01/31/2023]
Abstract
Sanitation is intended to reduce the spread and burden of diseases transmitted from excreta. Pathogen reduction from excreta before sludge or effluent discharge to the environment would seem a logical and useful performance indicator for sanitation systems. However, the relative magnitudes of pathogen release from common sanitation technologies are not well understood. We, therefore, investigated the feasibility of performance measurement of different sanitation technologies in Tamil Nadu, India in reducing the release of the pathogen indicator Escherichia coli (E. coli). After conducting users’ surveys and technical assessments of the locally prevalent sanitation systems, we classified them into 7 distinct categories (based on both observed physical characteristic and usage) within a widely-accepted physical typology. Faecal sludge and wastewater samples were collected and analysed for E. coli and total solids from 136 household systems, 24 community systems, and 23 sanitary sewer oveflows. We estimated the average volumetric release rates of wastewater and faecal sludge from the different sanitation technologies. Average daily per capita E. coli release was computed, and used as one indicator of the public health performance of technologies. We found that on-site installations described by owners as “septic systems” included diverse forms of tanks and pits of uncertain performance. We observed a statistically significant difference in the average daily per capita E. coli release from different sanitation technologies (p = 0.00001). Pathogen release from the studied on-site sanitation technologies varied by as much as 5 orders of magnitude from “lined pits” (5.4 Log10 E. coli per person per day) to “overflowing sanitary sewers” and “direct discharge pipes” (10.3–10.5 Log10 E. coli per person per day). Other technologies lay between these extremes, and their performances in E. coli removal also varied significantly, in both statistical and practical terms. Our results suggest that although faecal sludge management along the sanitation service chain is important, sanitation planners of the observed systems (and probably elsewhere) should direct higher priority to proper management of the liquid effluents from these systems to minimize public health hazards. We conclude that (i) the work demonstrates a new and promising approach for estimating the public health performance of differing sanitation technologies, (ii) if E.coli is accepted as an indicator of the public health hazard of releases from sanitation systems, our results strongly suggest that safe containment of excreta for an extended period substantially reduces pathogen numbers and the risk of pathogen release into the environment; and (iii) there are some simple but little-used technical improvements to design and construction of on-site sanitation systems which could significantly reduce the release of pathogens to the environment.
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Affiliation(s)
- Musa Manga
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA; Department of Construction Economics and Management, College of Engineering, Design, Art and Technology (CEDAT), Makerere University, P.O. Box 7062, Kampala, Uganda.
| | - Pete Kolsky
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
| | | | - Sudha Ramalingam
- PSG Institute of Medical Sciences and Research, Off, Avinashi Rd, Masakalipalayam, Peelamedu, Coimbatore, Tamil Nadu, 641004, India
| | - Lavanya Sriramajayam
- PSG Institute of Medical Sciences and Research, Off, Avinashi Rd, Masakalipalayam, Peelamedu, Coimbatore, Tamil Nadu, 641004, India
| | - Jamie Bartram
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA; School of Civil Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - Jill Stewart
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, NC, 27599, Chapel Hill, NC, USA
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13
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Khanam F, Ross AG, McMillan NAJ, Qadri F. Toward Typhoid Fever Elimination. Int J Infect Dis 2022; 119:41-43. [PMID: 35338009 DOI: 10.1016/j.ijid.2022.03.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/18/2022] [Accepted: 03/19/2022] [Indexed: 11/30/2022] Open
Abstract
Salmonella enterica serotype Typhi (S Typhi) causes typhoid fever and is responsible for an estimated 9 million cases and 110,000 deaths globally per annum. Typhoid fever is endemic in areas where water, sanitation, and hygiene (WaSH) infrastructure is poor. Serious complications develop in approximately 10%-15% of patients if left untreated, and this is driven by inadequate diagnostic methods and the high burden of antibiotic-resistant strains, complicating clinical management and ultimately prognosis. Asymptomatic chronic carriers, in addition to acutely infected patients, contribute to continued transmission through the shedding of the organism in the feces. The high morbidity and mortality of typhoid fever in low- and middle-income countries reinforce the need for an integrated control approach, which may ultimately lead to elimination of the disease in the 21st century. Here we discuss the challenges faced in pursuit of typhoid fever elimination.
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Affiliation(s)
- Farhana Khanam
- International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh.
| | - Allen G Ross
- Rural Health Research Institute, Charles Sturt University, Orange Campus, Australia
| | - Nigel A J McMillan
- Menzies Health Institute Queensland, University of Queensland, Gold Coast, Australia
| | - Firdausi Qadri
- International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
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14
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Wang Y, Mairinger W, Raj SJ, Yakubu H, Siesel C, Green J, Durry S, Joseph G, Rahman M, Amin N, Hassan MZ, Wicken J, Dourng D, Larbi E, Adomako LAB, Senayah AK, Doe B, Buamah R, Tetteh-Nortey JNN, Kang G, Karthikeyan A, Roy S, Brown J, Muneme B, Sene SO, Tuffuor B, Mugambe RK, Bateganya NL, Surridge T, Ndashe GM, Ndashe K, Ban R, Schrecongost A, Moe CL. Quantitative assessment of exposure to fecal contamination in urban environment across nine cities in low-income and lower-middle-income countries and a city in the United States. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:151273. [PMID: 34718001 PMCID: PMC8651627 DOI: 10.1016/j.scitotenv.2021.151273] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/23/2021] [Accepted: 10/23/2021] [Indexed: 05/06/2023]
Abstract
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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Affiliation(s)
- Yuke Wang
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Wolfgang Mairinger
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Suraja J Raj
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Habib Yakubu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Casey Siesel
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jamie Green
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Sarah Durry
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - George Joseph
- Water Global Practice, The World Bank, Washington, DC, USA
| | - Mahbubur Rahman
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Nuhu Amin
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | | | | | | | - Eugene Larbi
- Training Research and Networking for Development (TREND), Accra, Ghana
| | | | | | - Benjamin Doe
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard Buamah
- Department of Civil Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | | | - Gagandeep Kang
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Arun Karthikeyan
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Sheela Roy
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Joe Brown
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Bacelar Muneme
- Water Supply and Mapping, WE Consult, Maputo, Mozambique
| | - Seydina O Sene
- Initiative Prospective Agricole et Rurale (IPAR), Dakar, Senegal
| | - Benedict Tuffuor
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard K Mugambe
- Department of Disease Control and Environmental Health, Makerere University School of Public Health, Kampala, Uganda
| | - Najib Lukooya Bateganya
- Department of Environment and Public Health, Kampala Capital City Authority, Kampala, Uganda
| | - Trevor Surridge
- Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH, Lusaka, Zambia
| | | | - Kunda Ndashe
- Department of Environmental Health, Faculty of Health Science, Lusaka Apex Medical University, Lusaka, Zambia
| | - Radu Ban
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | | | - Christine L Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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15
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Wang Y, Mairinger W, Raj SJ, Yakubu H, Siesel C, Green J, Durry S, Joseph G, Rahman M, Amin N, Hassan MZ, Wicken J, Dourng D, Larbi E, Adomako LAB, Senayah AK, Doe B, Buamah R, Tetteh-Nortey JNN, Kang G, Karthikeyan A, Roy S, Brown J, Muneme B, Sene SO, Tuffuor B, Mugambe RK, Bateganya NL, Surridge T, Ndashe GM, Ndashe K, Ban R, Schrecongost A, Moe CL. Quantitative assessment of exposure to fecal contamination in urban environment across nine cities in low-income and lower-middle-income countries and a city in the United States. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 763:143007. [PMID: 34718001 DOI: 10.1016/j.scitotenv.2020.143007] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 05/23/2023]
Abstract
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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Affiliation(s)
- Yuke Wang
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Wolfgang Mairinger
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Suraja J Raj
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Habib Yakubu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Casey Siesel
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jamie Green
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Sarah Durry
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - George Joseph
- Water Global Practice, The World Bank, Washington, DC, USA
| | - Mahbubur Rahman
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Nuhu Amin
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | | | | | | | - Eugene Larbi
- Training Research and Networking for Development (TREND), Accra, Ghana
| | | | | | - Benjamin Doe
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard Buamah
- Department of Civil Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | | | - Gagandeep Kang
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Arun Karthikeyan
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Sheela Roy
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Joe Brown
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Bacelar Muneme
- Water Supply and Mapping, WE Consult, Maputo, Mozambique
| | - Seydina O Sene
- Initiative Prospective Agricole et Rurale (IPAR), Dakar, Senegal
| | - Benedict Tuffuor
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard K Mugambe
- Department of Disease Control and Environmental Health, Makerere University School of Public Health, Kampala, Uganda
| | - Najib Lukooya Bateganya
- Department of Environment and Public Health, Kampala Capital City Authority, Kampala, Uganda
| | - Trevor Surridge
- Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH, Lusaka, Zambia
| | | | - Kunda Ndashe
- Department of Environmental Health, Faculty of Health Science, Lusaka Apex Medical University, Lusaka, Zambia
| | - Radu Ban
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | | | - Christine L Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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Field Trial of an Automated Batch Chlorinator System at Two Shared Shallow Tubewells among Camps for Forcibly Displaced Myanmar Nationals (FDMN) in Cox's Bazar, Bangladesh. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182412917. [PMID: 34948527 PMCID: PMC8701840 DOI: 10.3390/ijerph182412917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 09/30/2021] [Accepted: 10/15/2021] [Indexed: 11/26/2022]
Abstract
Chlorination of shallow tubewell water is challenging due to various iron concentrations. A mixed-method, small-scale before-and-after field trial assessed the accuracy and consistency of an automated chlorinator, Zimba, in Rohingya camp housing, Cox’s Bazar. From August–September 2018, two shallow tubewells (iron concentration = 6.5 mg/L and 1.5 mg/L) were selected and 20 households were randomly enrolled to participate in household surveys and water testing. The field-team tested pre-and post-treated tubewell and household stored water for iron, free and total chlorine, and E. coli. A sub-set of households (n = 10) also received safe storage containers (5 L jerry cans). Overall mean iron concentrations were 5.8 mg/L in Zimba water, 1.9 mg/L in household storage containers, and 2.8 mg/L in the project-provided safe storage containers. At baseline, 0% samples at source and 60% samples stored in household vessels were contaminated with E. coli (mean log10 = 0.62 MPN/100 mL). After treatment, all water samples collected from source and project-provided safe storage containers were free from E. coli, but 41% of post-treated water stored in the household was contaminated with E. coli. E. coli concentrations were significantly lower in the project-provided safe storage containers (log10 mean difference = 0.92 MPN, 95% CI = 0.59–1.14) compared with baseline and post-treated water stored in household vessels (difference = 0.57 MPN, 95% CI = 0.32–0.83). Zimba is a potential water treatment technology for groundwater extracted through tubewells with different iron concentrations in humanitarian settings.
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17
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Smith DW, Islam M, Furst KE, Mustaree S, Crider YS, Akter N, Islam SA, Sultana S, Mahmud ZH, Rahman M, Mitch WA, Davis J. Chlorine taste can increase simulated exposure to both fecal contamination and disinfection byproducts in water supplies. WATER RESEARCH 2021; 207:117806. [PMID: 34768105 DOI: 10.1016/j.watres.2021.117806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/21/2021] [Accepted: 10/21/2021] [Indexed: 06/13/2023]
Abstract
Expanding drinking water chlorination could substantially reduce the burden of disease in low- and middle-income countries, but the taste of chlorinated water often impedes adoption. We developed a Monte Carlo simulation to estimate the effect of people's choice to accept or reject drinking water based on chlorine taste and their subsequent exposure to E. coli and trihalomethanes, a class of disinfection byproduct (DBP). The simulation used empirical data from Dhaka, Bangladesh, a megacity with endemic waterborne disease. We drew on published taste acceptability thresholds from Dhaka residents, measured residual chlorine and thermotolerant E. coli inactivation following the addition of six chlorine doses (0.25-3.0 mg/L as Cl2) to untreated piped water samples from 100 locations, and analyzed trihalomethane formation in 54 samples. A dose of 0.5 mg/L, 75% lower than the 2 mg/L dose typically recommended for household chlorination of low-turbidity waters, minimized overall exposure to E. coli. Doses of 1-2 mg/L maximized overall exposure to trihalomethanes. Accounting for chlorine taste aversion indicates that microbiological exposure increases and DBP exposure decreases above certain doses as a higher proportion of people reject chlorinated water in favor of untreated water. Taken together with findings from other modeling analyses, empirical studies, and field trials, our results suggest that taste acceptability should be a critical consideration in establishing chlorination dosing guidelines. Particularly when chlorination is first implemented in water supplies with low chlorine demand, lower doses than those generally recommended for household water treatment can help avoid taste-related objections while still meaningfully reducing contaminant exposure.
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Affiliation(s)
- Daniel W Smith
- Civil & Environmental Engineering, Stanford University, 473 Via Ortega, Y2E2 Building, Stanford, CA 94305, USA.
| | - Mahfuza Islam
- Environmental Interventions Unit, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Kirin E Furst
- Civil & Environmental Engineering, Stanford University, 473 Via Ortega, Y2E2 Building, Stanford, CA 94305, USA
| | - Shobnom Mustaree
- Environmental Microbiology Laboratory, icddr,b, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Yoshika S Crider
- Energy & Resources Group and Division of Epidemiology & Biostatistics, University of California Berkeley, 310 Barrows Hall, Berkeley, CA 94720, USA
| | - Nazrin Akter
- Environmental Interventions Unit, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Syed Anjerul Islam
- Environmental Interventions Unit, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Sonia Sultana
- Environmental Interventions Unit, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Zahid H Mahmud
- Environmental Microbiology Laboratory, icddr,b, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Mahbubur Rahman
- Environmental Interventions Unit, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - William A Mitch
- Civil & Environmental Engineering, Stanford University, 473 Via Ortega, Y2E2 Building, Stanford, CA 94305, USA
| | - Jennifer Davis
- Civil & Environmental Engineering, Stanford University, 473 Via Ortega, Y2E2 Building, Stanford, CA 94305, USA; Stanford Woods Institute for the Environment, Stanford University, 473 Via Ortega, Y2E2 Building, Stanford, CA 94305, USA
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18
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Islam A, Kalam MA, Sayeed MA, Shano S, Rahman MK, Islam S, Ferdous J, Choudhury SD, Hassan MM. Escalating SARS-CoV-2 circulation in environment and tracking waste management in South Asia. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:61951-61968. [PMID: 34558044 PMCID: PMC8459815 DOI: 10.1007/s11356-021-16396-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 09/03/2021] [Indexed: 04/15/2023]
Abstract
The novel coronavirus disease of 2019 (COVID-19) pandemic has caused an exceptional drift of production, utilization, and disposal of personal protective equipment (PPE) and different microplastic objects for safety against the virus. Hence, we reviewed related literature on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA detected from household, biomedical waste, and sewage to identify possible health risks and status of existing laws, regulations, and policies regarding waste disposal in South Asian (SA) countries. The SARS-CoV-2 RNA was detected in sewage and wastewater samples of Nepal, India, Pakistan, and Bangladesh. Besides, this review reiterates the enormous amounts of PPE and other single-use plastic wastes generated from healthcare facilities and households in the SA region with inappropriate disposal, landfilling, and/or incineration techniques wind-up polluting the environment. Consequently, the Delta variant (B.1.617.2) of SARS-CoV-2 has been detected in sewer treatment plant in India. Moreover, the overuse of non-biodegradable plastics during the pandemic is deteriorating plastic pollution condition and causes a substantial health risk to the terrestrial and aquatic ecosystems. We recommend making necessary adjustments, adopting measures and strategies, and enforcement of the existing biomedical waste management and sanitation-related policy in SA countries. We propose to adopt the knowledge gaps to improve COVID-19-associated waste management and legislation to prevent further environmental pollution. Besides, the citizens should follow proper disposal procedures of COVID-19 waste to control the environmental pollution.
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Affiliation(s)
- Ariful Islam
- EcoHealth Alliance, New York, NY, 10001-2320, USA.
- Centre for Integrative Ecology, School of Life and Environmental Science, Deakin University, Burwood, Victoria, 3216, Australia.
| | | | - Md Abu Sayeed
- EcoHealth Alliance, New York, NY, 10001-2320, USA
- Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, 1212, Bangladesh
| | - Shahanaj Shano
- EcoHealth Alliance, New York, NY, 10001-2320, USA
- Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, 1212, Bangladesh
| | - Md Kaisar Rahman
- EcoHealth Alliance, New York, NY, 10001-2320, USA
- Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, 1212, Bangladesh
| | - Shariful Islam
- EcoHealth Alliance, New York, NY, 10001-2320, USA
- Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, 1212, Bangladesh
| | - Jinnat Ferdous
- EcoHealth Alliance, New York, NY, 10001-2320, USA
- Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, 1212, Bangladesh
| | - Shusmita Dutta Choudhury
- EcoHealth Alliance, New York, NY, 10001-2320, USA
- Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, 1212, Bangladesh
| | - Mohammad Mahmudul Hassan
- Faculty of Veterinary Medicine, Chattogram Veterinary and Animal Sciences University, Chattogram, 4225, Bangladesh
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19
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Metagenome-Wide Analysis of Rural and Urban Surface Waters and Sediments in Bangladesh Identifies Human Waste as a Driver of Antibiotic Resistance. mSystems 2021; 6:e0013721. [PMID: 34254820 PMCID: PMC8407206 DOI: 10.1128/msystems.00137-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In many low- and middle-income countries, antibiotic-resistant bacteria spread in the environment due to inadequate treatment of wastewater and the poorly regulated use of antibiotics in agri- and aquaculture. Here, we characterized the abundance and diversity of antibiotic-resistant bacteria and antibiotic resistance genes in surface waters and sediments in Bangladesh through quantitative culture of extended-spectrum beta-lactamase (ESBL)-producing coliforms and shotgun metagenomics. Samples were collected from highly urbanized settings (n = 7), rural ponds with a history of aquaculture-related antibiotic use (n = 11), and rural ponds with no history of antibiotic use (n = 6). ESBL-producing coliforms were found to be more prevalent in urban samples than in rural samples. Shotgun sequencing showed that sediment samples were dominated by the phylum Proteobacteria (on average, 73.8% of assigned reads), while in the water samples, Cyanobacteria were the predominant phylum (on average, 60.9% of assigned reads). Antibiotic resistance genes were detected in all samples, but their abundance varied 1,525-fold between sites, with the highest levels of antibiotic resistance genes being present in urban surface water samples. The abundance of antibiotic resistance genes was significantly correlated (R2 = 0.73; P = 8.9 × 10−15) with the abundance of bacteria originating from the human gut, which suggests that the release of untreated sewage is a driver for the spread of environmental antibiotic resistance genes in Bangladesh, particularly in highly urbanized settings. IMPORTANCE Low- and middle-income countries (LMICs) have higher burdens of multidrug-resistant infections than high-income countries, and there is thus an urgent need to elucidate the drivers of the spread of antibiotic-resistant bacteria in LMICs. Here, we study the diversity and abundance of antibiotic resistance genes in surface water and sediments from rural and urban settings in Bangladesh. We found that urban surface waters are particularly rich in antibiotic resistance genes, with a higher number of them associated with plasmids, indicating that they are more likely to spread horizontally. The abundance of antibiotic resistance genes was strongly correlated with the abundance of bacteria that originate from the human gut, suggesting that uncontrolled release of human waste is a major driver for the spread of antibiotic resistance in the urban environment. Improvements in sanitation in LMICs may thus be a key intervention to reduce the dissemination of antibiotic-resistant bacteria.
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Khanam F, Darton TC, Ross AGP, Zaman K, Pollard AJ, Clemens JD, Qadri F. Case Report: Typhoid Fever Complicated by Ileal Perforation in an Urban Slum of Dhaka, Bangladesh. Am J Trop Med Hyg 2021; 104:1755-1757. [PMID: 33755582 PMCID: PMC8103489 DOI: 10.4269/ajtmh.20-1448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 01/11/2021] [Indexed: 11/07/2022] Open
Abstract
Intestinal perforation is one of the most dangerous complications of typhoid fever and demands urgent hospitalization, diagnosis, and surgical management to reduce morbidity and prevent mortality. Here, we report a case of typhoidal intestinal perforation in a 19 year-old young man detected by passive surveillance during a cluster-randomized trial with Vi-tetanus toxoid conjugate vaccine (Typhoid Vaccine Acceleration Consortium: TyVAC) in an urban slum area in Mirpur, Dhaka, Bangladesh. The patient presented with a high-grade fever, lower abdominal pain, and vomiting and was admitted to a healthcare facility. Physical examination and preoperative investigations of the patient suggested a presumptive diagnosis of intestinal perforation, and the patient was transferred to a tertiary-level hospital for surgical management. A positive blood culture, intraoperative findings, and histopathology of an intestinal biopsy confirmed ileal perforation due to typhoid fever. This case report highlights the need for prompt diagnosis and appropriate pre- and postoperative management of patients who appear with the symptoms of typhoidal intestinal perforation. This report further demonstrates the importance of systematic surveillance and proper evaluation to determine the true incidence rate of typhoid fever and intestinal perforation in Bangladesh.
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Affiliation(s)
- Farhana Khanam
- icddr,b, (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh;,School of Medical Science, Griffith University, Gold Coast, Australia
| | - Thomas C. Darton
- Department of Infection, Immunity and Cardiovascular Disease, The Florey Institute for Host-Pathogen Interactions, University of Sheffield, Sheffield, United Kingdom
| | - Allen G. P. Ross
- icddr,b, (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - K. Zaman
- icddr,b, (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Andrew J. Pollard
- Oxford Vaccine Group, Department of Paediatrics, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - John D. Clemens
- icddr,b, (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Firdausi Qadri
- icddr,b, (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh;,Address correspondence to Firdausi Qadri, Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sharani, Dhaka 1212, Bangladesh. E-mail:
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21
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Abir T, Ekwudu O, Kalimullah NA, Nur-A Yazdani DM, Al Mamun A, Basak P, Osuagwu UL, Permarupan PY, Milton AH, Talukder SH, Agho KE. Dengue in Dhaka, Bangladesh: Hospital-based cross-sectional KAP assessment at Dhaka North and Dhaka South City Corporation area. PLoS One 2021; 16:e0249135. [PMID: 33784366 PMCID: PMC8009423 DOI: 10.1371/journal.pone.0249135] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 03/11/2021] [Indexed: 11/19/2022] Open
Abstract
Dengue, the most important mosquito-borne viral disease of humans is a recurring global health problem. In Bangladesh, dengue outbreaks are on the increase despite the efforts of government and it is not clear what the understanding of the general Dhaka population towards dengue fever is. Knowledge, attitude and practice (KAP) studies are essential guides in public health interventions. Hence, using KAP, this study aims to assess patient-perspectives with regards to factors associated with dengue, as well as investigate the associated factors between the two corporations in Dhaka. A Hospital-based cross-sectional study of 242 fever patients from two city-corporations in Dhaka (Dhaka North City Corporations, DNCC (n = 91, 37.6%) and Dhaka South City Corporation, DSCC (n = 151, 62.4%) was conducted using pre-tested KAP items. Wilcoxon's Rank Sum was used to determine the KAP by DNCC, DSCC and both corporations and multivariate Poisson regression analyses. The two corporations were analysed separately due to the differences in income distribution, concentration of slums, hospitals and clinics. The study found that more than half of the study population were knowledgeable about dengue (mean percentage scores was 52%), possess an appropriate and acceptable attitude towards the disease (69.2%), and about two thirds of the respondents (71.4%) engaged in practices towards its prevention. After adjusting for the potential cofounders, the factors associated with KAP about dengue fever varied between DNCC and DSCC; with duration of residency and use of mosquito nets were associated with knowledge in the north while income class and age were associated with knowledge and attitude in the south. In the pooled analysis (combining both corporations), knowledge of dengue was associated with good practice towards dengue fever among the respondents. The duration of residence in Dhaka (10+ years), not using mosquito nets and length of time spent in the hospital (7+ days) due to dengue, and decreased knowledge (Adjusted coefficient (β) = -0.01, 95%CI: -0.02, -0.01) were associated with attitude towards dengue in DNCC. On the other hand, middle-high income class, age (40+ years) and increased knowledge were associated with practice towards dengue in DSCC (β = 0.02, 95%CI: 0.01, 0.03). Efforts to increase knowledge about dengue fever through education by the administrations of both corporations would benefit from targeting these high-risk groups for a more sustainable outcome.
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Affiliation(s)
- Tanvir Abir
- College of Business Administration, International University of Business, Agriculture and Technology, Dhaka, Bangladesh
| | - O’mezie Ekwudu
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | | | - Dewan Muhammad Nur-A Yazdani
- College of Business Administration, International University of Business, Agriculture and Technology, Dhaka, Bangladesh
| | - Abdullah Al Mamun
- Faculty of Business and Management, UCSI University, Kuala Lumpur, Malaysia
| | - Palash Basak
- School of Environment and Life Sciences (Environmental Science and Management), University of Newcastle, Callaghan, Australia
| | - Uchechukwu Levi Osuagwu
- Diabetes, Obesity, and Translational Research Unit (DOMTRU), School of Medicine, Western Sydney University, Sydney, Australia
| | | | | | | | - Kingsley E. Agho
- School of Health Sciences, Western Sydney University, Sydney, Australia
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22
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Foster T, Falletta J, Amin N, Rahman M, Liu P, Raj S, Mills F, Petterson S, Norman G, Moe C, Willetts J. Modelling faecal pathogen flows and health risks in urban Bangladesh: Implications for sanitation decision making. Int J Hyg Environ Health 2021; 233:113669. [PMID: 33578186 DOI: 10.1016/j.ijheh.2020.113669] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 11/19/2020] [Accepted: 11/24/2020] [Indexed: 12/29/2022]
Abstract
Faecal-oral infections are a major component of the disease burden in low-income contexts, with inadequate sanitation seen as a contributing factor. However, demonstrating health effects of sanitation interventions - particularly in urban areas - has proved challenging and there is limited empirical evidence to support sanitation decisions that maximise health gains. This study aimed to develop, apply and validate a systems modelling approach to inform sanitation infrastructure and service decision-making in urban environments by examining enteric pathogen inputs, transport and reduction by various sanitation systems, and estimating corresponding exposure and public health impacts. The health effects of eight sanitation options were assessed in a low-income area in Dhaka, Bangladesh, with a focus on five target pathogens (Shigella, Vibrio cholerae, Salmonella Typhi, norovirus GII and Giardia). Relative to the sanitation base case in the study site (24% septic tanks, 5% holding tanks and 71% toilets discharging directly to open drains), comprehensive coverage of septic tanks was estimated to reduce the disease burden in disability-adjusted life years (DALYs) by 48-72%, while complete coverage of communal scale anaerobic baffled reactors was estimated to reduce DALYs by 67-81%. Despite these improvements, a concerning health risk persists with these systems as a result of effluent discharge to open drains, particularly when the systems are poorly managed. Other sanitation options, including use of constructed wetlands and small bore sewerage, demonstrated further reductions in local health risk, though several still exported pathogens into neighbouring areas, simply transferring risk to downstream communities. The study revealed sensitivity to and a requirement for further evidence on log reduction values for different sanitation systems under varying performance conditions, pathogen flows under flooding conditions as well as pathogen shedding and human exposure in typical low-income urban settings. Notwithstanding variability and uncertainties in input parameters, systems modelling can be a feasible and customisable approach to consider the relative health impact of different sanitation options across various contexts, and stands as a valuable tool to guide urban sanitation decision-making.
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Affiliation(s)
- Tim Foster
- Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW, 2007, Australia.
| | - Jay Falletta
- Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW, 2007, Australia.
| | - Nuhu Amin
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh.
| | - Mahbubur Rahman
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh.
| | - Pengbo Liu
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Suraja Raj
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Freya Mills
- Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW, 2007, Australia.
| | - Susan Petterson
- Water & Health Pty Ltd., 13 Lord St, North Sydney, NSW, 2060, Australia; School of Medicine, Griffith University, Parklands Drive, Southport, QLD, 4222, Australia.
| | - Guy Norman
- Water and Sanitation for the Urban Poor, 10 Queen Street Place, London, EC4R 1BE, UK.
| | - Christine Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Juliet Willetts
- Institute for Sustainable Futures, University of Technology Sydney, 235 Jones St, Ultimo, NSW, 2007, Australia.
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Pandey D, Verma S, Verma P, Mahanty B, Dutta K, Daverey A, Arunachalam K. SARS-CoV-2 in wastewater: Challenges for developing countries. Int J Hyg Environ Health 2021; 231:113634. [PMID: 33039922 PMCID: PMC7539828 DOI: 10.1016/j.ijheh.2020.113634] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/15/2020] [Accepted: 09/30/2020] [Indexed: 12/12/2022]
Abstract
The COVID-19 pandemic that has engulfed the world, has affected the human lives in several aspects. The detection of SARS-CoV-2 in faeces and urine of the infected person, even after viral clearance in the respiratory tract, and its presence in untreated wastewater raises the possibility of fecal-oral transmission in future. The situation is likely to be more aggravated in developing and least developed countries struggling with the problem of ineffective waste disposal system, open defecation, poor sanitation, and limited access to clean drinking water. In this review, the available data on wastewater treatment, sanitation status and healthcare infrastructure from middle- and low-income countries is collected and correlated with the risk associated with the fecal-oral transmission of SARS-CoV-2. The review also highlights the limitation of COVID-19 surveillance through sewage monitoring in these countries owing to the absence of proper sewerage system. An inclusive approach of awareness, prevention, and mitigation from global to the local levels is required to overcome this challenging situation in developing countries.
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Affiliation(s)
- Deepshikha Pandey
- School of Environment and Natural Resources, Doon University, Dehradun, Uttarakhand, 248012, India
| | - Shelly Verma
- School of Environment and Natural Resources, Doon University, Dehradun, Uttarakhand, 248012, India
| | - Priyanka Verma
- School of Environment and Natural Resources, Doon University, Dehradun, Uttarakhand, 248012, India
| | - Biswanath Mahanty
- Department of Biotechnology, Karunya Institute of Technology and Sciences, Coimbatore, 641114, India
| | - Kasturi Dutta
- Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, Odisha, 769008, India
| | - Achlesh Daverey
- School of Environment and Natural Resources, Doon University, Dehradun, Uttarakhand, 248012, India.
| | - Kusum Arunachalam
- School of Environment and Natural Resources, Doon University, Dehradun, Uttarakhand, 248012, India.
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Pathogen flows from on-site sanitation systems in low-income urban neighborhoods, Dhaka: A quantitative environmental assessment. Int J Hyg Environ Health 2020; 230:113619. [PMID: 32942223 DOI: 10.1016/j.ijheh.2020.113619] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 08/16/2020] [Accepted: 08/27/2020] [Indexed: 01/17/2023]
Abstract
BACKGROUND Despite wide usage of on-site sanitation, there is limited field-based evidence on the removal or release of pathogens from septic tanks and other primary treatment systems, such as anaerobic baffled reactors (ABR). In two low-income areas in Dhaka, we conducted a cross-sectional study to explore pathogen loads discharged from commonly used on-site sanitation-systems and their transport in nearby drains and waterways. METHODS We collected samples of drain water, drain sediment, canal water, and floodwater from April-October 2019. Sludge, supernatant, and effluent samples were also collected from septic tanks and ABRs. We investigated the presence and concentration of selected enteric pathogens (Shigella, Vibrio cholerae (V. cholerae), Salmonella Typhi (S. Typhi), Norovirus Genogroup-II (NoV-GII), and Giardia) and presence of Cryptosporidium in these samples using quantitative polymerase chain reaction (qPCR).The equivalent genome copies (EGC) of individual pathogens were estimated in each sample by interpolation of the mean Ct value to the corresponding standard curve and the dilution factor for each sample type. Absolute quantification was expressed as log10 EGC per 100 mL for the water samples and log10 EGC per gram for the sediment samples. RESULTS Among all samples tested (N = 151), 89% were contaminated with Shigella, 68% with V. cholerae and NoV-GII, 32% with Giardia, 17% with S. Typhi and 6% with Cryptosporidium. A wide range of concentration of pathogens [range: mean log10 concentration of Giardia = 0.74 EGC/100 mL in drain ultrafiltration samples to mean log10 concentration of NoV-GII and Giardia = 7.11 EGC/100 mL in ABR sludge] was found in all environmental samples. The highest pathogen concentrations were detected in open drains [range: mean log10 concentration = 2.50-4.94 EGC/100 mL], septic tank effluent [range: mean log10 concentration = 3.32-4.65 EGC/100 mL], and ABR effluent [range: mean log10 concentration = 2.72-5.13 EGC/100 mL]. CONCLUSIONS High concentrations of pathogens (particularly NoV-GII, V.cholerae and Shigella) were frequently detected in environmental samples from two low-income urban neighbourhoods of Dhaka city. The numerous environmental exposure pathways for children and adults make these findings of public health concern. These results should prompt rethinking of how to achieve safe sanitation solutions that protect public health in dense low-income areas. In particular, improved management and maintenance regimes, further treatment of liquid effluent from primary treatment processes, and appropriate application of onsite, decentralised and offsite sanitation systems given the local context.
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Raj SJ, Wang Y, Yakubu H, Robb K, Siesel C, Green J, Kirby A, Mairinger W, Michiel J, Null C, Perez E, Roguski K, Moe CL. The SaniPath Exposure Assessment Tool: A quantitative approach for assessing exposure to fecal contamination through multiple pathways in low resource urban settlements. PLoS One 2020; 15:e0234364. [PMID: 32530933 PMCID: PMC7292388 DOI: 10.1371/journal.pone.0234364] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 05/23/2020] [Indexed: 11/18/2022] Open
Abstract
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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Affiliation(s)
- Suraja J. Raj
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
- * E-mail:
| | - Yuke Wang
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Habib Yakubu
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Katharine Robb
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Casey Siesel
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Jamie Green
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Amy Kirby
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Wolfgang Mairinger
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - James Michiel
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Clair Null
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Eddy Perez
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Katherine Roguski
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
| | - Christine L. Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America
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