ORCID Profile
0000-0003-0475-6465
Current Organisations
Delft University of Technology
,
Michigan State University
,
KWR Water Research Institute
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Publisher: Elsevier BV
Date: 2022
Publisher: Elsevier BV
Date: 08-2020
Publisher: MDPI AG
Date: 19-04-2021
DOI: 10.20944/PREPRINTS202104.0481.V1
Abstract: Wastewater surveillance for pathogens using the reverse transcription-polymerase chain reaction (RT-PCR) is an effective, resource-efficient tool for gathering additional community-level public health information, including the incidence and/or prevalence and trends of coronavirus disease-19 (COVID-19). Surveillance of SARS-CoV-2 in wastewater may provide an early-warning signal of COVID-19 infections in a community. The capacity of the world& rsquo s environmental microbiology and virology laboratories for SARS-CoV-2 RNA characterization in wastewater is rapidly increasing. However, there are no standardized protocols nor harmonized quality assurance and quality control (QA/QC) procedures for SARS-CoV-2 wastewater surveillance. This paper is a technical review of factors that can lead to false-positive and -negative errors in the surveillance of SARS-CoV-2, culminating in recommendations and strategies that can be implemented to identify and mitigate these errors. Recommendations include, stringent QA/QC measures, representative s ling approaches, effective virus concentration and efficient RNA extraction, lification inhibition assessment, inclusion of s le processing controls, and considerations for RT-PCR assay selection and data interpretation. Clear data interpretation guidelines (e.g., determination of positive and negative s les) are critical, particularly during a low incidence of SARS-CoV-2 in wastewater. Corrective and confirmatory actions must be in place for inconclusive and/or potentially significant results (e.g., initial onset or reemergence of COVID-19 in a community). It will also be prudent to perform inter-laboratory comparisons to ensure results are reliable and interpretable for ongoing and retrospective analyses. The strategies that are recommended in this review aim to improve SARS-CoV-2 characterization for wastewater surveillance applications. A silver lining of the COVID-19 pandemic is that the efficacy of wastewater surveillance was demonstrated during this global crisis. In the future, wastewater will play an important role in the surveillance of a range of other communicable diseases.
Publisher: Elsevier BV
Date: 07-2021
Publisher: American Chemical Society (ACS)
Date: 11-01-2006
DOI: 10.1021/ES0580237
Publisher: IWA Publishing
Date: 02-2022
DOI: 10.2166/WH.2022.185
Abstract: The COVID-19 pandemic has resulted in over 340 million infection cases (as of 21 January 2022) and more than 5.57 million deaths globally. In reaction, science, technology and innovation communities across the globe have organised themselves to contribute to national responses to COVID-19 disease. A significant contribution has been from the establishment of wastewater-based epidemiological (WBE) surveillance interventions and programmes for monitoring the spread of COVID-19 in at least 55 countries. Here, we examine and share experiences and lessons learnt in establishing such surveillance programmes. We use case studies to highlight testing methods and logistics considerations associated in scaling the implementing of such programmes in South Africa, the Netherlands, Turkey and England. The four countries were selected to represent different regions of the world and the perspective based on the considerable progress made in establishing and implementing their national WBE programmes. The selected countries also represent different climatic zones, economies, and development stages, which influence the implementation of national programmes of this nature and magnitude. In addition, the four countries' programmes offer good experiences and lessons learnt since they are systematic, and cover extensive areas, disseminate knowledge locally and internationally and partnered with authorities (government). The programmes also strengthened working relations and partnerships between and among local and global organisations. This paper shares these experiences and lessons to encourage others in the water and public health sectors on the benefits and value of WBE in tackling SARS-CoV-2 and related future circumstances.
Publisher: American Chemical Society (ACS)
Date: 30-08-2005
DOI: 10.1021/ES050427B
Abstract: To define protection zones around groundwater abstraction wells and safe setback distances for artificial recharge systems in watertreatment, quantitative information is needed about the removal of microorganisms during soil passage. Column experiments were conducted using natural soil and water from an infiltration site with fine sandy soil and a river bank infiltration site with gravel soil. The removal of phages, bacteria, bacterial spores, and protozoan (oo)-cysts was determined at two velocities and compared with field data from the same sites. The microbial elimination rate (MER) in both soils was generally >2 log, but MER in the gravel soil was higher than that in the fine sandy soil. This was attributed to enhanced attachment, related to higher metal-hydroxides content. From the high sticking efficiencies (>1) and the low influence of flow rate on MER it was deduced that straining played a significant role in the removal of Escherichia coli and Cryptosporidium parvum oocysts in the gravel soil. Lower removal of oocysts than the 4-5 times smaller E. coli and spores in the fine sand indicates that the contribution of straining is variable and needs further attention in transport models. Thus, simple extrapolation of grain size and particle size to the extent of microbial transport underground is inappropriate. Finally, the low MER of indigenous E. coli and Clostridium perfringens observed in the soil columns as well as under field conditions and the second breakthrough peak found for Cryptosporidium and spores in the fine sandy soil upon a change in the feedwater pH indicate a significant role of detachment and retardation to microbial transport and the difficulty of extrapolation of quantitative column test results to field conditions.
Publisher: IWA Publishing
Date: 09-2007
DOI: 10.2166/WH.2007.141
Abstract: The volume of cold tap water consumed is an essential element in quantitative microbial risk assessment. This paper presents a review of tap water consumption studies. Study designs were evaluated and statistical distributions were fitted to water consumption data from The Netherlands, Great Britain, Germany and Australia. We conclude that the diary is to be preferred for collecting water consumption data. If a diary is not feasible, a 24 h recall would be the best alternative, preferably repeated at least once. From the studies evaluated, the mean daily consumption varies from 0.10 L to 1.55 L. No conclusions could be drawn regarding the effects of season, age and gender on tap water consumption. Physical activity, yearly income and perceived health status were reported to influence water consumption. Comparison of the different statistical probability distribution functions of the datasets demonstrated that the Poisson distribution performed better than the lognormal distribution as suggested by Roseberry and Burmaster. For quantitative microbiological risk assessment (QMRA) it is recommended to use country-specific consumption data and statistical distributions, if available. If no country specific data are available we recommend to use the Australian distribution data from the Melbourne diary study (Poisson, λ=3.49 glasses/d) as a conservative estimate.
Publisher: Wiley
Date: 22-10-2021
Abstract: Risk assessment is critical for identifying target concentrations of antibiotic resistant pathogens necessary for mitigating potential harmful exposures associated with water reuse. However, there is currently limited available data characterizing the concentrations of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in recycled water to support robust efforts at risk assessment. The objective of this systematic review was to identify and synthesize the existing literature documenting the presence and abundance of ARB and ARGs in recycled water. In addition, this review identifies best practices and explores monitoring targets for studying ARB and ARGs in recycled water to guide future work and identifies key research needs aimed at better supporting quantitative microbial risk assessment focused on recycled water and antibiotic resistance. Future efforts to collect data about ARB and ARG prevalence in recycled water should report concentration data per unit volume. S le metadata should also be provided, including a description of treatment approach, a description of planned water uses (e.g., potable, irrigation), methods for conveyance to the point of use, and available physicochemical water quality data. Additional research is needed aimed at identifying recommended ARB and ARG monitoring targets and for developing approaches to incorporate metagenomic data into risk assessment.
No related grants have been discovered for Gertjan Medema.