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Länsivaara A, Lehto KM, Hyder R, Janhonen ES, Lipponen A, Heikinheimo A, Pitkänen T, Oikarinen S. Comparison of Different Reverse Transcriptase-Polymerase Chain Reaction-Based Methods for Wastewater Surveillance of SARS-CoV-2: Exploratory Study. JMIR Public Health Surveill 2024; 10:e53175. [PMID: 39158943 DOI: 10.2196/53175] [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: 09/28/2023] [Revised: 04/09/2024] [Accepted: 05/30/2024] [Indexed: 08/20/2024] Open
Abstract
BACKGROUND Many countries have applied the wastewater surveillance of the COVID-19 pandemic to their national public health monitoring measures. The most used methods for detecting SARS-CoV-2 in wastewater are quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) and reverse transcriptase-droplet digital polymerase chain reaction (RT-ddPCR). Previous comparison studies have produced conflicting results, thus more research on the subject is required. OBJECTIVE This study aims to compare RT-qPCR and RT-ddPCR for detecting SARS-CoV-2 in wastewater. It also aimed to investigate the effect of changes in the analytical pipeline, including the RNA extraction kit, RT-PCR kit, and target gene assay, on the results. Another aim was to find a detection method for low-resource settings. METHODS We compared 2 RT-qPCR kits, TaqMan RT-qPCR and QuantiTect RT-qPCR, and RT-ddPCR based on sensitivity, positivity rates, variability, and correlation of SARS-CoV-2 gene copy numbers in wastewater to the incidence of COVID-19. Furthermore, we compared 2 RNA extraction methods, column- and magnetic-bead-based. In addition, we assessed 2 target gene assays for RT-qPCR, N1 and N2, and 2 target gene assays for ddPCR N1 and E. Reverse transcription strand invasion-based amplification (RT-SIBA) was used to detect SARS-CoV-2 from wastewater qualitatively. RESULTS Our results indicated that the most sensitive method to detect SARS-CoV-2 in wastewater was RT-ddPCR. It had the highest positivity rate (26/30), and its limit of detection was the lowest (0.06 gene copies/µL). However, we obtained the best correlation between COVID-19 incidence and SARS-CoV-2 gene copy number in wastewater using TaqMan RT-qPCR (correlation coefficient [CC]=0.697, P<.001). We found a significant difference in sensitivity between the TaqMan RT-qPCR kit and the QuantiTect RT-qPCR kit, the first having a significantly lower limit of detection and a higher positivity rate than the latter. Furthermore, the N1 target gene assay was the most sensitive for both RT-qPCR kits, while no significant difference was found between the gene targets using RT-ddPCR. In addition, the use of different RNA extraction kits affected the result when the TaqMan RT-qPCR kit was used. RT-SIBA was able to detect SARS-CoV-2 RNA in wastewater. CONCLUSIONS As our study, as well as most of the previous studies, has shown RT-ddPCR to be more sensitive than RT-qPCR, its use in the wastewater surveillance of SARS-CoV-2 should be considered, especially if the amount of SARS-CoV-2 circulating in the population was low. All the analysis steps must be optimized for wastewater surveillance as our study showed that all the analysis steps including the compatibility of the RNA extraction, the RT-PCR kit, and the target gene assay influence the results. In addition, our study showed that RT-SIBA could be used to detect SARS-CoV-2 in wastewater if a qualitative result is sufficient.
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Affiliation(s)
- Annika Länsivaara
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Kirsi-Maarit Lehto
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Rafiqul Hyder
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | | | - Anssi Lipponen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Annamari Heikinheimo
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
- Finnish Food Authority - Ruokavirasto, Seinäjoki, Finland
| | - Tarja Pitkänen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Sami Oikarinen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
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Paracchini V, Petrillo M, Arcot Rajashekar A, Robuch P, Vincent U, Corbisier P, Tavazzi S, Raffael B, Suffredini E, La Rosa G, Gawlik BM, Marchini A. EU surveys insights: analytical tools, future directions, and the essential requirement for reference materials in wastewater monitoring of SARS-CoV-2, antimicrobial resistance and beyond. Hum Genomics 2024; 18:72. [PMID: 38937848 PMCID: PMC11210120 DOI: 10.1186/s40246-024-00641-5] [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: 03/13/2024] [Accepted: 06/17/2024] [Indexed: 06/29/2024] Open
Abstract
BACKGROUND Wastewater surveillance (WWS) acts as a vigilant sentinel system for communities, analysing sewage to protect public health by detecting outbreaks and monitoring trends in pathogens and contaminants. To achieve a thorough comprehension of present and upcoming practices and to identify challenges and opportunities for standardisation and improvement in WWS methodologies, two EU surveys were conducted targeting over 750 WWS laboratories across Europe and other regions. The first survey explored a diverse range of activities currently undertaken or planned by laboratories. The second survey specifically targeted methods and quality controls utilised for SARS-CoV-2 surveillance. RESULTS The findings of the two surveys provide a comprehensive insight into the procedures and methodologies applied in WWS. In Europe, WWS primarily focuses on SARS-CoV-2 with 99% of the survey participants dedicated to this virus. However, the responses highlighted a lack of standardisation in the methodologies employed for monitoring SARS-CoV-2. The surveillance of other pathogens, including antimicrobial resistance, is currently fragmented and conducted by only a limited number of laboratories. Notably, these activities are anticipated to expand in the future. Survey replies emphasise the collective recognition of the need to enhance the accuracy of results in WWS practices, reflecting a shared commitment to advancing precision and effectiveness in WWS methodologies. CONCLUSIONS These surveys identified a lack of standardised common procedures in WWS practices and the need for quality standards and reference materials to enhance the accuracy and reliability of WWS methods in the future. In addition, it is important to broaden surveillance efforts beyond SARS-CoV-2 to include other emerging pathogens and antimicrobial resistance to ensure a comprehensive approach to protecting public health.
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Affiliation(s)
| | | | | | - Piotr Robuch
- European Commission, Joint Research Centre (JRC), Geel, Belgium
| | - Ursula Vincent
- European Commission, Joint Research Centre (JRC), Geel, Belgium
| | | | - Simona Tavazzi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Barbara Raffael
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Elisabetta Suffredini
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità (ISS), Rome, Italy
| | - Giuseppina La Rosa
- National Center for Water Safety (CeNSia), Istituto Superiore di Sanità (ISS), Rome, Italy
| | | | - Antonio Marchini
- European Commission, Joint Research Centre (JRC), Geel, Belgium.
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Li Y, Huang K, Yin J, Tan Z, Zhou M, Dai J, Yi B. Clinical evaluation of a multiplex droplet digital PCR for pathogen detection in critically ill COVID-19 patients with bloodstream infections. Infection 2024; 52:1027-1039. [PMID: 38127118 PMCID: PMC11143000 DOI: 10.1007/s15010-023-02157-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 12/05/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND Nosocomial bloodstream infections (nBSI) have emerged as a clinical concern for physicians treating COVID-19 patients. In this study, we aimed to evaluate the effectiveness of a multiplex ddPCR in detecting bacterial pathogens in the blood of COVID-19 critically ill patients. METHODS This prospective diagnostic study included RT-PCR-confirmed COVID-19 patients admitted to our hospital from December 2022 to February 2023. A multiplex ddPCR assay was used to detect common bacterial pathogens and AMR genes in blood samples of the patients, along with antimicrobial susceptibility testing (AST). The diagnostic performance of the ddPCR assay was evaluated by comparing the results with those obtained through blood culture and clinical diagnosis. Additionally, the ability of ddPCR in detecting bacterial resistance was compared with the AST results. RESULTS Of the 200 blood samples collected from 184 patients, 45 (22.5%) were positive using blood culture, while 113 (56.5%) were positive for bacterial targets using the ddPCR assay. The ddPCR assay outperformed blood culture in pathogen detection rate, mixed infection detection rate, and fungal detection rate. Acinetobacter baumannii and Klebsiella pneumoniae were the most commonly detected pathogens in COVID-19 critically ill patients, followed by Enterococcus and Streptococcus. Compared to blood culture, ddPCR achieved a sensitivity of 75.5%, specificity of 51.0%, PPV of 30.9%, and NPV of 87.8%, respectively. However, there were significant differences in sensitivity among different bacterial species, where Gram-negative bacteria have the highest sensitivity of 90.3%. When evaluated on the ground of clinical diagnosis, the sensitivity, specificity, PPV and NPV of ddPCR were 78.1%, 90.5%, 94.7%, and 65.5%, respectively. In addition, the ddPCR assay detected 23 cases of blaKPC, which shown a better consistent with clinical test results than other detected AMR genes. Compared to blaKPC, there were few other AMR genes detected, indicating that the application of other AMR gene detection in the COVID-19 critically ill patients was limited. CONCLUSION The multiplex ddPCR assay had a significantly higher pathogen detection positivity than the blood culture, which could be an effective diagnostic tool for BSIs in COVID-19 patients and to improve patient outcomes and reduce the burden of sepsis on the healthcare system, though there is room for optimization of the panels used.- Adjusting the targets to include E. faecalis and E. faecium as well as Candida albicans and Candida glabrata could improve the ddPCR' s effectiveness. However, further research is needed to explore the potential of ddPCR in predicting bacterial resistance through AMR gene detection.
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Affiliation(s)
- Yanbing Li
- Department of Laboratory Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, People's Republic of China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China
| | - Kangkang Huang
- Department of Laboratory Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, People's Republic of China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China
| | - Jun Yin
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China
| | - Zheren Tan
- Intensive Care Unit, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China
| | - Manli Zhou
- Department of Laboratory Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, People's Republic of China
| | - Jiaoyang Dai
- Department of Laboratory Medicine, Xiangya Medical School, Central South University, Changsha, Hunan, 410008, People's Republic of China
| | - Bin Yi
- Department of Laboratory Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, People's Republic of China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China.
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de la Cruz Barron M, Kneis D, Geissler M, Dumke R, Dalpke A, Berendonk TU. Evaluating the sensitivity of droplet digital PCR for the quantification of SARS-CoV-2 in wastewater. Front Public Health 2023; 11:1271594. [PMID: 38425410 PMCID: PMC10903512 DOI: 10.3389/fpubh.2023.1271594] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 11/27/2023] [Indexed: 03/02/2024] Open
Abstract
Wastewater surveillance for SARS-CoV-2 has been demonstrated to be a valuable tool in monitoring community-level virus circulation and assessing new outbreaks. It may become a useful tool in the early detection and response to future pandemics, enabling public health authorities to implement timely interventions and mitigate the spread of infectious diseases with the fecal excretion of their agents. It also offers a chance for cost-effective surveillance. Reverse transcription-quantitative polymerase chain reaction (RTqPCR) is the most commonly used method for viral RNA detection in wastewater due to its sensitivity, reliability, and widespread availability. However, recent studies have indicated that reverse transcription droplet digital PCR (RTddPCR) has the potential to offer improved sensitivity and accuracy for quantifying SARS-CoV-2 RNA in wastewater samples. In this study, we compared the performance of RTqPCR and RTddPCR approaches for SARS-CoV-2 detection and quantification on wastewater samples collected during the third epidemic wave in Saxony, Germany, characterized by low-incidence infection periods. The determined limits of detection (LOD) and quantification (LOQ) were within the same order of magnitude, and no significant differences were observed between the PCR approaches with respect to the number of positive or quantifiable samples. Our results indicate that both RTqPCR and RTddPCR are highly sensitive methods for detecting SARS-CoV-2. Consequently, the actual gain in sensitivity associated with ddPCR lags behind theoretical expectations. Hence, the choice between the two PCR methods in further environmental surveillance programs is rather a matter of available resources and throughput requirements.
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Affiliation(s)
| | - David Kneis
- Institute of Hydrobiology, Technische Universität Dresden, Dresden, Germany
| | - Michael Geissler
- Institute of Medical Microbiology and Virology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Roger Dumke
- Institute of Medical Microbiology and Virology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Alexander Dalpke
- Institute of Medical Microbiology and Virology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Department of Infectious Diseases, Medical Microbiology and Hygiene, University Heidelberg, Heidelberg, Germany
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Wilhelm A, Schoth J, Meinert-Berning C, Bastian D, Blum H, Elsinga G, Graf A, Heijnen L, Ho J, Kluge M, Krebs S, Stange C, Uchaikina A, Dolny R, Wurzbacher C, Drewes JE, Medema G, Tiehm A, Ciesek S, Teichgräber B, Wintgens T, Weber FA, Widera M. Interlaboratory comparison using inactivated SARS-CoV-2 variants as a feasible tool for quality control in COVID-19 wastewater monitoring. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166540. [PMID: 37634730 DOI: 10.1016/j.scitotenv.2023.166540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/11/2023] [Accepted: 08/22/2023] [Indexed: 08/29/2023]
Abstract
Wastewater-based SARS-CoV-2 epidemiology (WBE) has proven as an excellent tool to monitor pandemic dynamics supporting individual testing strategies. WBE can also be used as an early warning system for monitoring the emergence of novel pathogens or viral variants. However, for a timely transmission of results, sophisticated sample logistics and analytics performed in decentralized laboratories close to the sampling sites are required. Since multiple decentralized laboratories commonly use custom in-house workflows for sample purification and PCR-analysis, comparative quality control of the analytical procedures is essential to report reliable and comparable results. In this study, we performed an interlaboratory comparison at laboratories specialized for PCR and high-throughput-sequencing (HTS)-based WBE analysis. Frozen reserve samples from low COVID-19 incidence periods were spiked with different inactivated authentic SARS-CoV-2 variants in graduated concentrations and ratios. Samples were sent to the participating laboratories for analysis using laboratory specific methods and the reported viral genome copy numbers and the detection of viral variants were compared with the expected values. All PCR-laboratories reported SARS-CoV-2 genome copy equivalents (GCE) for all spiked samples with a mean intra- and inter-laboratory variability of 19 % and 104 %, respectively, largely reproducing the spike-in scheme. PCR-based genotyping was, in dependence of the underlying PCR-assay performance, able to predict the relative amount of variant specific substitutions even in samples with low spike-in amount. The identification of variants by HTS, however, required >100 copies/ml wastewater and had limited predictive value when analyzing at a genome coverage below 60 %. This interlaboratory test demonstrates that despite highly heterogeneous isolation and analysis procedures, overall SARS-CoV-2 GCE and mutations were determined accurately. Hence, decentralized SARS-CoV-2 wastewater monitoring is feasible to generate comparable analysis results. However, since not all assays detected the correct variant, prior evaluation of PCR and sequencing workflows as well as sustained quality control such as interlaboratory comparisons are mandatory for correct variant detection.
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Affiliation(s)
- Alexander Wilhelm
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Paul-Ehrlich-Str. 40, D-60596 Frankfurt, Germany
| | - Jens Schoth
- Emschergenossenschaft/Lippeverband, Kronprinzenstraße 24, D-45128 Essen, Germany
| | | | - Daniel Bastian
- FiW e.V., Research Institute for Water Management and Climate Future at RWTH Aachen University, Kackertstraße 15-17, D-52056 Aachen, Germany
| | - Helmut Blum
- Laboratory for Functional Genome Analysis, Gene Center, LMU München, Feodor-Lynen-Straße 25, D-81377 Munich, Germany
| | - Goffe Elsinga
- KWR Water Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, the Netherlands
| | - Alexander Graf
- Laboratory for Functional Genome Analysis, Gene Center, LMU München, Feodor-Lynen-Straße 25, D-81377 Munich, Germany
| | - Leo Heijnen
- KWR Water Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, the Netherlands
| | - Johannes Ho
- TZW: DVGW-Technologiezentrum Wasser, Karlsruher Str. 84, 76139 Karlsruhe, Germany
| | - Mariana Kluge
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, D-85748 Garching, Germany
| | - Stefan Krebs
- Laboratory for Functional Genome Analysis, Gene Center, LMU München, Feodor-Lynen-Straße 25, D-81377 Munich, Germany
| | - Claudia Stange
- TZW: DVGW-Technologiezentrum Wasser, Karlsruher Str. 84, 76139 Karlsruhe, Germany
| | - Anna Uchaikina
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, D-85748 Garching, Germany
| | - Regina Dolny
- Institute of Environmental Engineering, RWTH Aachen University, Mies-van-der-Rohe-Strasse 1, D-52074 Aachen, Germany
| | - Christian Wurzbacher
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, D-85748 Garching, Germany
| | - Jörg E Drewes
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, D-85748 Garching, Germany
| | - Gertjan Medema
- KWR Water Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, the Netherlands
| | - Andreas Tiehm
- TZW: DVGW-Technologiezentrum Wasser, Karlsruher Str. 84, 76139 Karlsruhe, Germany
| | - Sandra Ciesek
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Paul-Ehrlich-Str. 40, D-60596 Frankfurt, Germany; German Center for Infection Research (DZIF), 38124 Braunschweig, Germany; Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Theodor-Stern-Kai 7, D 60595 Frankfurt am Main, Germany
| | - Burkhard Teichgräber
- Emschergenossenschaft/Lippeverband, Kronprinzenstraße 24, D-45128 Essen, Germany
| | - Thomas Wintgens
- Institute of Environmental Engineering, RWTH Aachen University, Mies-van-der-Rohe-Strasse 1, D-52074 Aachen, Germany
| | - Frank-Andreas Weber
- FiW e.V., Research Institute for Water Management and Climate Future at RWTH Aachen University, Kackertstraße 15-17, D-52056 Aachen, Germany
| | - Marek Widera
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Paul-Ehrlich-Str. 40, D-60596 Frankfurt, Germany.
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Thapar I, Langan LM, Davis H, Norman RS, Bojes HK, Brooks BW. Influence of storage conditions and multiple freeze-thaw cycles on N1 SARS-CoV-2, PMMoV, and BCoV signal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165098. [PMID: 37392884 PMCID: PMC10307669 DOI: 10.1016/j.scitotenv.2023.165098] [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: 03/28/2023] [Revised: 06/16/2023] [Accepted: 06/21/2023] [Indexed: 07/03/2023]
Abstract
Wastewater-based epidemiology/wastewater-based surveillance (WBE/WBS) continues to serve as an effective means of monitoring various diseases, including COVID-19 and the emergence of SARS-CoV-2 variants, at the population level. As the use of WBE expands, storage conditions of wastewater samples will play a critical role in ensuring the accuracy and reproducibility of results. In this study, the impacts of water concentration buffer (WCB), storage temperature, and freeze-thaw cycles on the detection of SARS-CoV-2 and other WBE-related gene targets were examined. Freeze-thawing of concentrated samples did not significantly affect (p > 0.05) crossing/cycle threshold (Ct) value for any of the gene targets studied (SARS-CoV-2 N1, PMMoV, and BCoV). However, use of WCB during concentration resulted in a significant (p < 0.05) decrease in Ct for all targets, and storage at -80 °C (in contrast to -20 °C) appeared preferable for wastewater storage signal stability based on decreased Ct values, although this was only significantly different (p < 0.05) for the BCoV target. Interestingly, when Ct values were converted to gene copies per influent sample, no significant differences (p > 0.05) were observed in any of the targets examined. Stability of RNA targets in concentrated wastewater against freeze-thaw degradation supports archiving of concentrated samples for use in retrospective examination of COVID-19 trends and tracing SARS-CoV-2 variants and potentially other viruses, and provides a starting point for establishing a consistent procedure for specimen collection and storage for the WBE/WBS community.
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Affiliation(s)
- Isha Thapar
- Department of Environmental Science, Baylor University, One Bear Place #97266, Waco, TX 76798, USA
| | - Laura M Langan
- Department of Environmental Science, Baylor University, One Bear Place #97266, Waco, TX 76798, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, One Bear Place #97178, Waco, TX 76798, USA.
| | - Haley Davis
- Department of Environmental Science, Baylor University, One Bear Place #97266, Waco, TX 76798, USA; Harbor Branch Oceanographic Institute, Florida Atlantic University, 5600 US-1, Fort Pierce, FL 34946, USA
| | - R Sean Norman
- Department of Environmental Health Sciences, Arnold School of Public Health, South Carolina, 921 Assembly St., Columbia, SC 29208, USA
| | - Heidi K Bojes
- Environmental Epidemiology and Disease Registries Section, Texas Department of State Health Services, Austin, TX 78756, USA
| | - Bryan W Brooks
- Department of Environmental Science, Baylor University, One Bear Place #97266, Waco, TX 76798, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, One Bear Place #97178, Waco, TX 76798, USA; Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA
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