1
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Burnor E, Morin CW, Shirai JH, Zhou NA, Meschke JS. Development of a computational model to inform environmental surveillance sampling plans for Salmonella enterica serovar Typhi in wastewater. PLoS Negl Trop Dis 2024; 18:e0011468. [PMID: 38551999 PMCID: PMC11020695 DOI: 10.1371/journal.pntd.0011468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 04/16/2024] [Accepted: 02/14/2024] [Indexed: 04/18/2024] Open
Abstract
Typhoid fever-an acute febrile disease caused by infection with the bacterium Salmonella enterica serotype Typhi (S. Typhi)-continues to be a leading cause of global morbidity and mortality, particularly in developing countries with limited access to safe drinking water and adequate sanitation. Environmental surveillance, the process of detecting and enumerating disease-causing agents in wastewater, is a useful tool to monitor the circulation of typhoid fever in endemic regions. The design of environmental surveillance sampling plans and the interpretation of sampling results is complicated by a high degree of uncertainty and variability in factors that affect the final measured pathogens in wastewater samples, such as pathogen travel time through a wastewater network, pathogen dilution, decay and degradation, and laboratory processing methods. Computational models can, to an extent, assist in the design of sampling plans and aid in the evaluation of how different contributing factors affect sampling results. This study presents a computational model combining dynamic and probabilistic modeling techniques to estimate-on a spatial and temporal scale-the approximate probability of detecting S. Typhi within a wastewater system. This model may be utilized to inform environmental surveillance sampling plans and may provide useful insight into selecting appropriate sampling locations and times and interpreting results. A simulated applied modeling scenario is presented to demonstrate the model's functionality for aiding an environmental surveillance study in a typhoid-endemic community.
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Affiliation(s)
- Elisabeth Burnor
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, Washington, United States of America
| | - Cory W. Morin
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, Washington, United States of America
| | - Jeffry H. Shirai
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, Washington, United States of America
| | - Nicolette A. Zhou
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, Washington, United States of America
| | - John Scott Meschke
- Department of Environmental and Occupational Health Sciences, University of Washington School of Public Health, Seattle, Washington, United States of America
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2
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Hooda Y, Islam S, Kabiraj R, Rahman H, Sarkar H, da Silva KE, Raju RS, Luby SP, Andrews JR, Saha SK, Saha S. Old tools, new applications: Use of environmental bacteriophages for typhoid surveillance and evaluating vaccine impact. PLoS Negl Trop Dis 2024; 18:e0011822. [PMID: 38358956 PMCID: PMC10868810 DOI: 10.1371/journal.pntd.0011822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 11/27/2023] [Indexed: 02/17/2024] Open
Abstract
Typhoid-conjugate vaccines (TCVs) provide an opportunity to reduce the burden of typhoid fever, caused by Salmonella Typhi, in endemic areas. As policymakers design vaccination strategies, accurate and high-resolution data on disease burden is crucial. However, traditional blood culture-based surveillance is resource-extensive, prohibiting its large-scale and sustainable implementation. Salmonella Typhi is a water-borne pathogen, and here, we tested the potential of Typhi-specific bacteriophage surveillance in surface water bodies as a low-cost tool to identify where Salmonella Typhi circulates in the environment. In 2021, water samples were collected and tested for the presence of Salmonella Typhi bacteriophages at two sites in Bangladesh: urban capital city, Dhaka, and a rural district, Mirzapur. Salmonella Typhi-specific bacteriophages were detected in 66 of 211 (31%) environmental samples in Dhaka, in comparison to 3 of 92 (3%) environmental samples from Mirzapur. In the same year, 4,620 blood cultures at the two largest pediatric hospitals of Dhaka yielded 215 (5%) culture-confirmed typhoid cases, and 3,788 blood cultures in the largest hospital of Mirzapur yielded 2 (0.05%) cases. 75% (52/69) of positive phage samples were collected from sewage. All isolated phages were tested against a panel of isolates from different Salmonella Typhi genotypes circulating in Bangladesh and were found to exhibit a diverse killing spectrum, indicating that diverse bacteriophages were isolated. These results suggest an association between the presence of Typhi-specific phages in the environment and the burden of typhoid fever, and the potential of utilizing environmental phage surveillance as a low-cost tool to assist policy decisions on typhoid control.
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Affiliation(s)
- Yogesh Hooda
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | | | | | | | - Kesia E. da Silva
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | | | - Stephen P. Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Samir K. Saha
- Child Health Research Foundation, Dhaka, Bangladesh
- Department of Microbiology, Bangladesh Shishu Hospital and Institute, Dhaka, Bangladesh
| | - Senjuti Saha
- Child Health Research Foundation, Dhaka, Bangladesh
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3
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Wang Y, Liu P, VanTassell J, Hilton SP, Guo L, Sablon O, Wolfe M, Freeman L, Rose W, Holt C, Browning M, Bryan M, Waller L, Teunis PFM, Moe CL. When case reporting becomes untenable: Can sewer networks tell us where COVID-19 transmission occurs? WATER RESEARCH 2023; 229:119516. [PMID: 37379453 PMCID: PMC9763902 DOI: 10.1016/j.watres.2022.119516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 12/11/2022] [Accepted: 12/18/2022] [Indexed: 06/30/2023]
Abstract
Monitoring SARS-CoV-2 in wastewater is a valuable approach to track COVID-19 transmission. Designing wastewater surveillance (WWS) with representative sampling sites and quantifiable results requires knowledge of the sewerage system and virus fate and transport. We developed a multi-level WWS system to track COVID-19 in Atlanta using an adaptive nested sampling strategy. From March 2021 to April 2022, 868 wastewater samples were collected from influent lines to wastewater treatment facilities and upstream community manholes. Variations in SARS-CoV-2 concentrations in influent line samples preceded similar variations in numbers of reported COVID-19 cases in the corresponding catchment areas. Community sites under nested sampling represented mutually-exclusive catchment areas. Community sites with high SARS-CoV-2 detection rates in wastewater covered high COVID-19 incidence areas, and adaptive sampling enabled identification and tracing of COVID-19 hotspots. This study demonstrates how a well-designed WWS provides actionable information including early warning of surges in cases and identification of disease hotspots.
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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 30322, USA
| | - Pengbo Liu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Jamie VanTassell
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Stephen P Hilton
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Lizheng Guo
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Orlando Sablon
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Marlene Wolfe
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Lorenzo Freeman
- City of Atlanta Department of Watershed Management, Atlanta, GA 30303, USA
| | - Wayne Rose
- City of Atlanta Department of Watershed Management, Atlanta, GA 30303, USA
| | - Carl Holt
- City of Atlanta Department of Watershed Management, Atlanta, GA 30303, USA
| | - Mikita Browning
- City of Atlanta Department of Watershed Management, Atlanta, GA 30303, USA
| | - Michael Bryan
- Georgia Department of Public Health, Atlanta, GA 30303, USA
| | - Lance Waller
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Peter F M Teunis
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, 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 30322, USA
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4
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Kim K, Ban MJ, Kim S, Park MH, Stenstrom MK, Kang JH. Optimal allocation and operation of sewer monitoring sites for wastewater-based disease surveillance: A methodological proposal. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 320:115806. [PMID: 35926387 PMCID: PMC9342910 DOI: 10.1016/j.jenvman.2022.115806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/15/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Wastewater-based epidemiology (WBE) is drawing increasing attention as a promising tool for an early warning of emerging infectious diseases such as COVID-19. This study demonstrated the utility of a spatial bisection method (SBM) and a global optimization algorithm (i.e., genetic algorithm, GA), to support better designing and operating a WBE program for disease surveillance and source identification. The performances of SBM and GA were compared in determining the optimal locations of sewer monitoring manholes to minimize the difference among the effective spatial monitoring scales of the selected manholes. While GA was more flexible in determining the spatial resolution of the monitoring areas, SBM allows stepwise selection of optimal sampling manholes with equiareal subcatchments and lowers computational cost. Upon detecting disease outbreaks at a regular sewer monitoring site, additional manholes within the catchment can be selected and monitored to identify source areas with a required spatial resolution. SBM offered an efficient method for rapidly searching for the optimal locations of additional sampling manholes to identify the source areas. This study provides strategic and technical elements of WBE including sampling site selection with required spatial resolution and a source identification method.
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Affiliation(s)
- Keugtae Kim
- Department of Environmental and Energy Engineering, The University of Suwon, 17 Wauan-gil, Bongdam-eup, Hwaseong-si, Gyeonggi-do, 18323, Republic of Korea
| | - Min Jeong Ban
- Department of Civil and Environmental Engineering, Dongguk University-Seoul, 30, Pildong-ro 1gil, Jung-gu, Seoul, 04620, Republic of Korea
| | - Sungpyo Kim
- Department of Environmental Engineering, Korea University-Sejong, 2 511, Sejong-ro, Sejong City, 30019, Republic of Korea
| | - Mi-Hyun Park
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Michael K Stenstrom
- Department of Civil and Environmental Engineering, University of California, Los Angeles, CA, 90096, USA
| | - Joo-Hyon Kang
- Department of Civil and Environmental Engineering, Dongguk University-Seoul, 30, Pildong-ro 1gil, Jung-gu, Seoul, 04620, Republic of Korea.
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5
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Wang Y, Liu P, Zhang H, Ibaraki M, VanTassell J, Geith K, Cavallo M, Kann R, Saber L, Kraft CS, Lane M, Shartar S, Moe C. Early warning of a COVID-19 surge on a university campus based on wastewater surveillance for SARS-CoV-2 at residence halls. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 821:153291. [PMID: 35090922 PMCID: PMC8788089 DOI: 10.1016/j.scitotenv.2022.153291] [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: 09/08/2021] [Revised: 01/15/2022] [Accepted: 01/16/2022] [Indexed: 05/05/2023]
Abstract
As COVID-19 continues to spread globally, monitoring the disease at different scales is critical to support public health decision making. Surveillance for SARS-CoV-2 RNA in wastewater can supplement surveillance based on diagnostic testing. In this paper, we report the results of wastewater-based COVID-19 surveillance on Emory University campus that included routine sampling of sewage from a hospital building, an isolation/quarantine building, and 21 student residence halls between July 13th, 2020 and March 14th, 2021. We examined the sensitivity of wastewater surveillance for detecting COVID-19 cases at building level and the relation between Ct values from RT-qPCR results of wastewater samples and the number of COVID-19 patients residing in the building. Our results show that weekly wastewater surveillance using Moore swab samples was not sensitive enough (6 of 63 times) to reliably detect one or two sporadic cases in a residence building. The Ct values of the wastewater samples over time from the same sampling location reflected the temporal trend in the number of COVID-19 patients in the isolation/quarantine building and hospital (Pearson's r < -0.8), but there is too much uncertainty to directly estimate the number of COVID-19 cases using Ct values. After students returned for the spring 2021 semester, SARS-CoV-2 RNA was detected in the wastewater samples from most of the student residence hall monitoring sites one to two weeks before COVID-19 cases surged on campus. This finding suggests that wastewater-based surveillance can be used to provide early warning of COVID-19 outbreaks at institutions.
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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.
| | - Pengbo Liu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Haisu Zhang
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Makoto Ibaraki
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jamie VanTassell
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Kelly Geith
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Matthew Cavallo
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Rebecca Kann
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Lindsay Saber
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Colleen S Kraft
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA; Division of Infectious Diseases, Emory University, Atlanta, GA, USA
| | - Morgan Lane
- Division of Infectious Diseases, Emory University, Atlanta, GA, USA
| | - Samuel Shartar
- Emory University Office of Critical Event Preparedness and Response, Atlanta, GA, USA
| | - Christine 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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6
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Liu P, Ibaraki M, VanTassell J, Geith K, Cavallo M, Kann R, Guo L, Moe CL. A sensitive, simple, and low-cost method for COVID-19 wastewater surveillance at an institutional level. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:151047. [PMID: 34673061 PMCID: PMC8522675 DOI: 10.1016/j.scitotenv.2021.151047] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 09/16/2021] [Accepted: 10/13/2021] [Indexed: 05/08/2023]
Abstract
SARS-CoV-2 is a respiratory virus, but it is also detected in a significant proportion of fecal samples from COVID-19 cases. Recent studies have shown that wastewater surveillance can be a low-cost tool compared to massive diagnostic testing for tracking COVID-19 outbreaks in communities, but most studies have focused on sampling from wastewater treatment plants. Institutional level wastewater surveillance may serve well for early warning purposes because specific geographic areas/populations with emerging cases can be tracked and immediate action can be executed in the event of a positive wastewater signal. In this study, a novel Moore swab method was developed and used for wastewater surveillance of COVID-19 at an institutional level. Of the 442 swab samples tested, 148 (33.5%) swabs collected from the three campuses and two buildings were positive for SARS-CoV-2 RNA. Further study of the quarantine building with a known number of cases indicated that this method was sensitive enough to detect few cases in the building. In addition, comparison between grab samples and Moore swab samples from the hospital sewage line indicated that Moore swabs were more sensitive than grab samples and offer a simple, inexpensive method for obtaining a composite sample of virus in wastewater over a 24-48 h period. These results suggest that collection and analyses of Moore swabs for SARS-CoV-2 RNA detection is a sensitive, low-cost, and easy to use tool for COVID-19 surveillance that is useful for institutional settings and could be deployed in low-resource settings to identify emerging COVID-19 clusters in communities.
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Affiliation(s)
- Pengbo Liu
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA.
| | - Makoto Ibaraki
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Jamie VanTassell
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Kelly Geith
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Matthew Cavallo
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Rebecca Kann
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Lizheng Guo
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Christine L Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA.
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7
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Calle E, Martínez D, Brugués-I-Pujolràs R, Farreras M, Saló-Grau J, Pueyo-Ros J, Corominas L. Optimal selection of monitoring sites in cities for SARS-CoV-2 surveillance in sewage networks. ENVIRONMENT INTERNATIONAL 2021; 157:106768. [PMID: 34325220 PMCID: PMC8430229 DOI: 10.1016/j.envint.2021.106768] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/25/2021] [Accepted: 07/06/2021] [Indexed: 05/16/2023]
Abstract
Selecting sampling points to monitor traces of SARS-CoV-2 in sewage at the intra-urban scale is no trivial task given the complexity of the networks and the multiple technical, economic and socio-environmental constraints involved. This paper proposes two algorithms for the automatic selection of sampling locations in sewage networks. The first algorithm, is for the optimal selection of a predefined number of sampling locations ensuring maximum coverage of inhabitants and minimum overlapping amongst selected sites (static approach). The second is for establishing a strategy of iterations of sample&analysis to identify patient zero and hot spots of COVID-19 infected inhabitants in cities (dynamic approach). The algorithms are based on graph-theory and are coupled to a greedy optimization algorithm. The usefulness of the algorithms is illustrated in the case study of Girona (NE Iberian Peninsula, 148,504 inhabitants). The results show that the algorithms are able to automatically propose locations for a given number of stations. In the case of Girona, always covering more than 60% of the manholes and with less than 3% of them overlapping amongst stations. Deploying 5, 6 or 7 stations results in more than 80% coverage in manholes and more than 85% of the inhabitants. For the dynamic sensor placement, we demonstrate that assigning infection probabilities to each manhole as a function of the number of inhabitants connected reduces the number of iterations required to detect the zero patient and the hot spot areas.
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Affiliation(s)
- Eusebi Calle
- Institute of Informatics and Applications, Universitat de Girona, Girona, Spain.
| | - David Martínez
- Catalan Institute for Water Research, Emili Grahit 101, 17003 Girona, Spain.
| | | | - Miquel Farreras
- Institute of Informatics and Applications, Universitat de Girona, Girona, Spain.
| | - Joan Saló-Grau
- Institute of Informatics and Applications, Universitat de Girona, Girona, Spain.
| | - Josep Pueyo-Ros
- Catalan Institute for Water Research, Emili Grahit 101, 17003 Girona, Spain.
| | - Lluís Corominas
- Catalan Institute for Water Research, Emili Grahit 101, 17003 Girona, Spain.
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8
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Liu P, Ibaraki M, Kapoor R, Amin N, Das A, Miah R, Mukhopadhyay AK, Rahman M, Dutta S, Moe CL. Development of Moore Swab and Ultrafiltration Concentration and Detection Methods for Salmonella Typhi and Salmonella Paratyphi A in Wastewater and Application in Kolkata, India and Dhaka, Bangladesh. Front Microbiol 2021; 12:684094. [PMID: 34335510 PMCID: PMC8320291 DOI: 10.3389/fmicb.2021.684094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 06/23/2021] [Indexed: 11/16/2022] Open
Abstract
Enteric fever is a severe systemic infection caused by Salmonella enterica serovar Typhi (ST) and Salmonella enterica serovar Paratyphi A (SPA). Detection of ST and SPA in wastewater can be used as a surveillance strategy to determine burden of infection and identify priority areas for water, sanitation, and hygiene interventions and vaccination campaigns. However, sensitive and specific detection of ST and SPA in environmental samples has been challenging. In this study, we developed and validated two methods for concentrating and detecting ST/SPA from wastewater: the Moore swab trap method for qualitative results, and ultrafiltration (UF) for sensitive quantitative detection, coupled with qPCR. We then applied these methods for ST and SPA wastewater surveillance in Kolkata, India and Dhaka, Bangladesh, two enteric fever endemic areas. The qPCR assays had a limit of detection of 17 equivalent genome copies (EGC) for ST and 25 EGC for SPA with good reproducibility. In seeded trials, the Moore swab method had a limit of detection of approximately 0.05–0.005 cfu/mL for both ST and SPA. In 53 Moore swab samples collected from three Kolkata pumping stations between September 2019 and March 2020, ST was detected in 69.8% and SPA was detected in 20.8%. Analysis of sewage samples seeded with known amount of ST and SPA and concentrated via the UF method, followed by polyethylene glycol precipitation and qPCR detection demonstrated that UF can effectively recover approximately 8, 5, and 3 log10 cfu of seeded ST and SPA in 5, 10, and 20 L of wastewater. Using the UF method in Dhaka, ST was detected in 26.7% (8/30) of 20 L drain samples with a range of 0.11–2.10 log10 EGC per 100 mL and 100% (4/4) of 20 L canal samples with a range of 1.02–2.02 log10 EGC per 100 mL. These results indicate that the Moore swab and UF methods provide sensitive presence/absence and quantitative detection of ST/SPA in wastewater samples.
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Affiliation(s)
- Pengbo Liu
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Makoto Ibaraki
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Renuka Kapoor
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Nuhu Amin
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease, Bangladesh (ICDDR,B), Dhaka, Bangladesh
| | - Abhishek Das
- Indian Council of Medical Research (ICMR), National Institute of Cholera and Enteric Diseases (NICID), Kolkata, India
| | - Rana Miah
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease, Bangladesh (ICDDR,B), Dhaka, Bangladesh
| | - Asish K Mukhopadhyay
- Indian Council of Medical Research (ICMR), National Institute of Cholera and Enteric Diseases (NICID), Kolkata, India
| | - Mahbubur Rahman
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease, Bangladesh (ICDDR,B), Dhaka, Bangladesh
| | - Shanta Dutta
- Indian Council of Medical Research (ICMR), National Institute of Cholera and Enteric Diseases (NICID), Kolkata, India
| | - Christine L Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, GA, United States
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9
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Goddard FB, Ban R, Barr DB, Brown J, Cannon J, Colford JM, Eisenberg JNS, Ercumen A, Petach H, Freeman MC, Levy K, Luby SP, Moe C, Pickering AJ, Sarnat JA, Stewart J, Thomas E, Taniuchi M, Clasen T. Measuring Environmental Exposure to Enteric Pathogens in Low-Income Settings: Review and Recommendations of an Interdisciplinary Working Group. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:11673-11691. [PMID: 32813503 PMCID: PMC7547864 DOI: 10.1021/acs.est.0c02421] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 05/06/2023]
Abstract
Infections with enteric pathogens impose a heavy disease burden, especially among young children in low-income countries. Recent findings from randomized controlled trials of water, sanitation, and hygiene interventions have raised questions about current methods for assessing environmental exposure to enteric pathogens. Approaches for estimating sources and doses of exposure suffer from a number of shortcomings, including reliance on imperfect indicators of fecal contamination instead of actual pathogens and estimating exposure indirectly from imprecise measurements of pathogens in the environment and human interaction therewith. These shortcomings limit the potential for effective surveillance of exposures, identification of important sources and modes of transmission, and evaluation of the effectiveness of interventions. In this review, we summarize current and emerging approaches used to characterize enteric pathogen hazards in different environmental media as well as human interaction with those media (external measures of exposure), and review methods that measure human infection with enteric pathogens as a proxy for past exposure (internal measures of exposure). We draw from lessons learned in other areas of environmental health to highlight how external and internal measures of exposure can be used to more comprehensively assess exposure. We conclude by recommending strategies for advancing enteric pathogen exposure assessments.
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Affiliation(s)
- Frederick
G. B. Goddard
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Radu Ban
- Bill and
Melinda Gates Foundation, Seattle, Washington 98109, United States
| | - Dana Boyd Barr
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Joe Brown
- School of
Civil and Environmental Engineering, Georgia
Institute of Technology, Atlanta, Georgia 30332, United States
| | - Jennifer Cannon
- Centers
for Disease Control and Prevention Foundation, Atlanta, Georgia 30308, United States
| | - John M. Colford
- Division
of Epidemiology and Biostatistics, School of Public Health, University of California−Berkeley, Berkeley, California 94720, United States
| | - Joseph N. S. Eisenberg
- Department
of Epidemiology, University of Michigan
School of Public Health, Ann Arbor, Michigan 48109, United States
| | - Ayse Ercumen
- Department
of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Helen Petach
- U.S. Agency
for International Development, Washington, DC 20004, United States
| | - Matthew C. Freeman
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Karen Levy
- Department
of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington 98105, United States
| | - Stephen P. Luby
- Division
of Infectious Diseases and Geographic Medicine, Stanford University, California 94305, United States
| | - Christine Moe
- Center
for
Global Safe Water, Sanitation and Hygiene, Rollins School of Public
Health, Emory University, Atlanta, Georgia 30322, United States
| | - Amy J. Pickering
- Department
of Civil and Environmental Engineering, School of Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Jeremy A. Sarnat
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Jill Stewart
- Department
of Environmental Sciences and Engineering, Gillings School of Global
Public Health, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Evan Thomas
- Mortenson
Center in Global Engineering, University
of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Mami Taniuchi
- Division
of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Thomas Clasen
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| |
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