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1.
Int J Environ Res Public Health ; 19(1)2021 12 28.
Article in English | MEDLINE | ID: covidwho-1580804

ABSTRACT

The research aims at washing processes as possible sources of microplastics, specifical microfibers in wastewater, and the behavior of the virus particles SARS-CoV-2 in wastewater after the washing process as well as their ability to sorb to the surface of microfibers, released from washing processes. The conclusions of the research point to the ability of the virus to attach to possible solid impurities such as textile fibers (microfibers) occurring in the sewer and to the ability of wash water to influence their possible occurrence in the sewer. The highest efficiency (more than 99%) of removal virus particles was after washing process, using liquid washing powder, and washing soda. These findings may gradually contribute to a better understanding of the behavior of the virus particles in the sewer.


Subject(s)
COVID-19 , Water Pollutants, Chemical , Humans , Microplastics , Plastics , SARS-CoV-2 , Textiles , Waste Water , Water Pollutants, Chemical/analysis
2.
Int J Environ Res Public Health ; 19(1)2021 12 30.
Article in English | MEDLINE | ID: covidwho-1580781

ABSTRACT

Medical wastewater originating from hospitals specializing in infectious diseases pose a major risk to human and environmental health during pandemics. However, there have been few systematic studies on the management of this type of wastewater management. The function of the Huoshenshan Hospital as a designated emergency field hospital for the treatment of COVID-19 has provided lessons for the management measures of medical wastewater, mainly including: (1) Modern information technology, management schemes, and related standard systems provided the legislative foundation for emergency management of medical wastewater. (2) The three-tier prevention and control medical wastewater management system ensured the discharged wastewater met water quality standards, especially for the leak-proof sealed collection system of the first tier, and the biological and chemical treatment technology of the second tier. (3) The establishment of an effective three-tier medical wastewater quality monitoring accountability system. This system was particularly relevant for ensuring continuous data monitoring and dynamic analysis of characteristic indicators. (4) Information disclosure by government and public supervision promoted successful implementation of medical wastewater management and control measures. Public questionnaires (n = 212) further confirmed the effectiveness of information disclosure. The results of this study can act as methodological reference for the emergency management of wastewater in designated infectious disease hospitals under similar situations.


Subject(s)
COVID-19 , Communicable Diseases , China , Communicable Diseases/epidemiology , Hospitals , Humans , SARS-CoV-2 , Waste Water
3.
Curr Opin Microbiol ; 64: 91-99, 2021 12.
Article in English | MEDLINE | ID: covidwho-1575357

ABSTRACT

Antimicrobial resistance (AMR) is a growing global health threat that requires coordinated action across One Health sectors (humans, animals, environment) to stem its spread. Environmental surveillance of AMR is largely behind the curve in current One Health surveillance programs, but recent momentum in the establishment of infrastructure for monitoring of the SARS-CoV-2 virus in sewage provides an impetus for analogous AMR monitoring. Simultaneous advances in research have identified striking trends in various AMR measures in wastewater and other impacted environments across global transects. Methodologies for tracking AMR, including metagenomics, are rapidly advancing, but need to be standardized and made modular for access by LMICs, while also developing systems for sample archiving and data sharing. Such efforts will help optimize effective global AMR policy.


Subject(s)
COVID-19 , Drug Resistance, Bacterial , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Humans , SARS-CoV-2 , Waste Water
4.
J Environ Manage ; 304: 114296, 2022 Feb 15.
Article in English | MEDLINE | ID: covidwho-1568834

ABSTRACT

Wastewater-based epidemiology (WBE) for severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) is a powerful tool to complement syndromic surveillance. Although detection of SARS-CoV-2 in raw wastewater may be prompted with good recoveries during periods of high community prevalence, in the early stages of population outbreaks concentration procedures are required to overcome low viral concentrations. Several methods have become available for the recovery of SARS-CoV-2 from raw wastewater, generally involving filtration. However, these methods are limited to small sample volumes, possibly missing the early stages of virus circulation, and restrained applicability across different water matrices. The aim of this study was thus to evaluate the performance of three methods enabling the concentration of SARS-CoV-2 from large volumes of wastewater: i) hollow fiber filtration using the inuvai R180, with an enhanced elution protocol and polyethylene glycol (PEG) precipitation; ii) PEG precipitation; and iii) skimmed milk flocculation. The performance of the three approaches was evaluated in wastewater from multiple wastewater treatment plants (WWTP) with distinct singularities, according to: i) effective volume; ii) percentage of recovery; iii) extraction efficiency; iv) inhibitory effect; and v) the limits of detection and quantification. The inuvai R180 system had the best performance, with detection of spiked control across all samples, with average recovery percentages of 68% for porcine epidemic diarrhea virus (PEDV), with low variability. Mean recoveries for PEG precipitation and skimmed milk flocculation were 9% and 14%, respectively. The inuvai R180 enables the scalability of volumes without negative impact on the costs, time for analysis, and recovery/inhibition. Moreover, hollow fiber ultrafilters favor the concentration of different microbial taxonomic groups. Such combined features make this technology attractive for usage in environmental waters monitoring.


Subject(s)
COVID-19 , Viruses , Animals , Humans , SARS-CoV-2 , Swine , Waste Water
5.
Lancet Planet Health ; 5(12): e874-e881, 2021 12.
Article in English | MEDLINE | ID: covidwho-1565675

ABSTRACT

BACKGROUND: Wastewater-based epidemiology provides an opportunity for near real-time, cost-effective monitoring of community-level transmission of SARS-CoV-2. Detection of SARS-CoV-2 RNA in wastewater can identify the presence of COVID-19 in the community, but methods for estimating the numbers of infected individuals on the basis of wastewater RNA concentrations are inadequate. METHODS: This is a wastewater-based epidemiology study using wastewater samples that were collected weekly or twice a week from three sewersheds in South Carolina, USA, between either May 27 or June 16, 2020, and Aug 25, 2020, and tested for SARS-CoV-2 RNA. We developed a susceptible-exposed-infectious-recovered (SEIR) model based on the mass rate of SARS-CoV-2 RNA in the wastewater to predict the number of infected individuals, and have also provided a simplified equation to predict this. Model predictions were compared with the number of confirmed cases identified by the Department of Health and Environmental Control, South Carolina, USA, for the same time period and geographical area. FINDINGS: We plotted the model predictions for the relationship between mass rate of virus release and numbers of infected individuals, and we validated this prediction on the basis of estimated prevalence from individual testing. A simplified equation to estimate the number of infected individuals fell within the 95% confidence limits of the model. The rate of unreported COVID-19 cases, as estimated by the model, was approximately 11 times that of confirmed cases (ie, ratio of estimated infections for every confirmed case of 10·9, 95% CI 4·2-17·5). This rate aligned well with an independent estimate of 15 infections for every confirmed case in the US state of South Carolina. INTERPRETATION: The SEIR model provides a robust method to estimate the total number of infected individuals in a sewershed on the basis of the mass rate of RNA copies released per day. This approach overcomes some of the limitations associated with individual testing campaigns and thereby provides an additional tool that can be used to inform policy decisions. FUNDING: Clemson University, USA.


Subject(s)
COVID-19 , Humans , RNA, Viral , SARS-CoV-2 , Waste Water
6.
Emerg Infect Dis ; 27(12): 3111-3114, 2021.
Article in English | MEDLINE | ID: covidwho-1556358

ABSTRACT

We used wastewater surveillance to identify 2 coronavirus disease outbreaks at a college in Maine, USA. Cumulative increases of >1 log10 severe acute respiratory syndrome coronavirus 2 RNA in consecutive 24-hour composite samples preceded the outbreaks. For 76% of cases, RNA was identified in grab samples from residence halls <7 days before case discovery.


Subject(s)
COVID-19 , Waste Water , Humans , Maine , SARS-CoV-2 , Wastewater-Based Epidemiological Monitoring
7.
Environ Monit Assess ; 193(7): 449, 2021 Jun 26.
Article in English | MEDLINE | ID: covidwho-1549458

ABSTRACT

Treatment of water contaminated with heavy metals is challenging. Heavy metals are non-degradable, persistent in the environment, have a high dispersion capacity by water, can bioaccumulate, and represent risks to human and environmental health. Conventional treatment methods have disadvantages; however, adsorption in biomass is a highly promising method with high efficiency and low cost that avoids many of the disadvantages of conventional methods. Black tea (BT) wastes and water hyacinth (WH) have attracted attention for their ability to remove heavy metals from wastewater. Utilizing these approaches can remove contaminants and effectively manage problematic invasive species and wastes. The conventional uses of BT and WH were efficient for removing heavy metals from wastewater. Due to the unique and distinct properties and advantages of biochar and nano-forms of biosorbents, the use of BT and WH in these forms is promising to achieve sustainable heavy metals removal from wastewater. However, more study is needed to confirm preliminary results.


Subject(s)
Eichhornia , Metals, Heavy , Water Pollutants, Chemical , Adsorption , Environmental Monitoring , Humans , Metals, Heavy/analysis , Tea , Waste Water , Water Pollutants, Chemical/analysis
8.
Environ Int ; 158: 106998, 2022 01.
Article in English | MEDLINE | ID: covidwho-1549776

ABSTRACT

Since many infected people experience no or few symptoms, the SARS-CoV-2 epidemic is frequently monitored through massive virus testing of the population, an approach that may be biased and may be difficult to sustain in low-income countries. Since SARS-CoV-2 RNA can be detected in stool samples, quantifying SARS-CoV-2 genome by RT-qPCR in wastewater treatment plants (WWTPs) has been carried out as a complementary tool to monitor virus circulation among human populations. However, measuring SARS-CoV-2 viral load in WWTPs can be affected by many experimental and environmental factors. To circumvent these limits, we propose here a novel indicator, the wastewater indicator (WWI), that partly reduces and corrects the noise associated with the SARS-CoV-2 genome quantification in wastewater (average noise reduction of 19%). All data processing results in an average correlation gain of 18% with the incidence rate. The WWI can take into account the censorship linked to the limit of quantification (LOQ), allows the automatic detection of outliers to be integrated into the smoothing algorithm, estimates the average measurement error committed on the samples and proposes a solution for inter-laboratory normalization in the absence of inter-laboratory assays (ILA). This method has been successfully applied in the context of Obépine, a French national network that has been quantifying SARS-CoV-2 genome in a representative sample of French WWTPs since March 5th 2020. By August 26th, 2021, 168 WWTPs were monitored in the French metropolitan and overseas territories of France. We detail the process of elaboration of this indicator, show that it is strongly correlated to the incidence rate and that the optimal time lag between these two signals is only a few days, making our indicator an efficient complement to the incidence rate. This alternative approach may be especially important to evaluate SARS-CoV-2 dynamics in human populations when the testing rate is low.


Subject(s)
COVID-19 , Epidemics , Humans , RNA, Viral , SARS-CoV-2 , Waste Water
9.
Sci Total Environ ; 799: 149386, 2021 Dec 10.
Article in English | MEDLINE | ID: covidwho-1545398

ABSTRACT

To support public-health-related disease surveillance and monitoring, it is crucial to concentrate both enveloped and non-enveloped viruses from domestic wastewater. To date, most concentration methods were developed for non-enveloped viruses, and limited studies have directly compared the recovery efficiency of both types of viruses. In this study, the effectiveness of two different concentration methods (Concentrating pipette (CP) method and an adsorption-extraction (AE) method amended with MgCl2) were evaluated for untreated wastewater matrices using three different viruses (SARS-CoV-2 (seeded), human adenovirus 40/41 (HAdV 40/41), and enterovirus (EV)) and a wastewater-associated bacterial marker gene targeting Lachnospiraceae (Lachno3). For SARS-CoV-2, the estimated mean recovery efficiencies were significantly greater by as much as 5.46 times, using the CP method than the AE method amended with MgCl2. SARS-CoV-2 RNA recovery was greater for samples with higher titer seeds regardless of the method, and the estimated mean recovery efficiencies using the CP method were 25.1 ± 11% across ten WWTPs when wastewater samples were seeded with 5 × 104 gene copies (GC) of SARS-CoV-2. Meanwhile, the AE method yielded significantly greater concentrations of indigenous HAdV 40/41 and Lachno3 from wastewater compared to the CP method. Finally, no significant differences in indigenous EV concentrations were identified in comparing the AE and CP methods. These data indicate that the most effective concentration method varies by microbial analyte and that the priorities of the surveillance or monitoring program should be considered when choosing the concentration method.


Subject(s)
COVID-19 , Enterovirus , Viruses , Enterovirus/genetics , Humans , RNA, Viral , SARS-CoV-2 , Sewage , Waste Water
10.
Microbiol Spectr ; 9(2): e0079221, 2021 10 31.
Article in English | MEDLINE | ID: covidwho-1526452

ABSTRACT

A wastewater surveillance program targeting a university residence hall was implemented during the spring semester 2021 as a proactive measure to avoid an outbreak of COVID-19 on campus. Over a period of 7 weeks from early February through late March 2021, wastewater originating from the residence hall was collected as grab samples 3 times per week. During this time, there was no detection of SARS-CoV-2 by reverse transcriptase quantitative PCR (RT-qPCR) in the residence hall wastewater stream. Aiming to obtain a sample more representative of the residence hall community, a decision was made to use passive samplers beginning in late March onwards. Adopting a Moore swab approach, SARS-CoV-2 was detected in wastewater samples just 2 days after passive samplers were deployed. These samples also tested positive for the B.1.1.7 (Alpha) variant of concern (VOC) using RT-qPCR. The positive result triggered a public health case-finding response, including a mobile testing unit deployed to the residence hall the following day, with testing of nearly 200 students and staff, which identified two laboratory-confirmed cases of Alpha variant COVID-19. These individuals were relocated to a separate quarantine facility, averting an outbreak on campus. Aggregating wastewater and clinical data, the campus wastewater surveillance program has yielded the first estimates of fecal shedding rates of the Alpha VOC of SARS-CoV-2 in individuals from a nonclinical setting. IMPORTANCE Among early adopters of wastewater monitoring for SARS-CoV-2 have been colleges and universities throughout North America, many of whom are using this approach to monitor congregate living facilities for early evidence of COVID-19 infection as an integral component of campus screening programs. Yet, while there have been numerous examples where wastewater monitoring on a university campus has detected evidence for infection among community members, there are few examples where this monitoring triggered a public health response that may have averted an actual outbreak. This report details a wastewater-testing program targeting a residence hall on a university campus during spring 2021, when there was mounting concern globally over the emergence of SARS-CoV-2 variants of concern, reported to be more transmissible than the wild-type Wuhan strain. In this communication, we present a clear example of how wastewater monitoring resulted in actionable responses by university administration and public health, which averted an outbreak of COVID-19 on a university campus.


Subject(s)
COVID-19/epidemiology , Disease Outbreaks , SARS-CoV-2/isolation & purification , Universities , Waste Water/virology , Wastewater-Based Epidemiological Monitoring , COVID-19/transmission , COVID-19/virology , Humans , Mass Screening , Ontario , Public Health , SARS-CoV-2/classification , SARS-CoV-2/genetics
11.
Sci Total Environ ; 800: 149578, 2021 Dec 15.
Article in English | MEDLINE | ID: covidwho-1525945

ABSTRACT

In the current pandemic of COVID-19, sewage surveillance of SARS-CoV-2 genome has been used to complement viral epidemiology in different countries. The aim of this work was to introduce and evaluate this wastewater-based tool in the metropolitan region of Buenos Aires, Argentina. As a pilot study, surveillance of SARS-CoV-2 in wastewater from three districts of this area was performed for more than nine months from June 2020 to April 2021. Viruses present in the samples were concentrated using polyethylene glycol precipitation and quantified using RT-qPCR CDC N1 assay. Virus recovery for SARS-CoV-2 and a potential surrogate, bovine coronavirus Mebus strain, that shares the Betacoronavirus genus and structural characteristics with SARS-CoV-2, were evaluated after concentration and detection procedures. Recovery of both viruses did not differ significantly, with a median for SARS-CoV-2 and BCoV of 0.085 (95% CI: 0.021-0.179) and 0.262 (95% CI: 1.18 × 10-5-0.564) respectively. The concentration of SARS-CoV-2 genome in wastewater ranged from 10 -1 to 10 3 cg/ml, depending on the wastewater treatment plant, type of collection site, viral recovery of the concentration method and the epidemiological situation of the outbreaks. Significant correlations were observed between SARS-CoV-2 concentration in wastewater and reported clinical cases, reinforcing the utility of this approach to monitor the epidemiological status of populations.


Subject(s)
COVID-19 , Waste Water , Animals , Argentina/epidemiology , Cattle , Humans , Pilot Projects , SARS-CoV-2
12.
Sci Total Environ ; 800: 149298, 2021 Dec 15.
Article in English | MEDLINE | ID: covidwho-1525944

ABSTRACT

Human coronaviruses (HCoVs) attracted attention in 2002 with the severe acute respiratory syndrome (SARS) outbreak, caused by the SARS-CoV virus (mortality rate 9.6%), and gained further notoriety in 2012 with the Middle East respiratory syndrome (MERS) (mortality rate 34.3%). Currently, the world is experiencing an unprecedented crisis due to the COVID-19 global pandemic, caused by the SARS-CoV-2 virus in 2019. The virus can pass to the faeces of some patients, as was the case of SARS-CoV and MERS-CoV viruses. This suggests that apart from the airborne (droplets and aerosols) and person-to-person (including fomites) transmission, the faecal-oral route of transmission could also be possible for HCoVs. In this eventuality, natural water bodies could act as a virus reservoir of infection. Here, the temporospatial migration and attenuation of the SARS-CoV-2 virus in municipal wastewater, the receiving environment, and drinking water is evaluated, using the polymerase chain reaction (PCR), in the South African setting. SARS-CoV-2 viral RNA was identified in raw wastewater influent but was below the detection limit in the latter treatment stages. This suggests that the virus decays from as early as primary treatment and this could be attributed to wastewater's hydraulic retention time (2-4 h), composition, and more importantly temperature (>25 °C). Therefore, the probability of SARS-CoV-2 virus transportation in water catchments, in the eventuality that the virus remains infective in wastewater, appears to be low in the South African setting. Finally, catchment-wide monitoring offers a snapshot of the status of the catchment in relation to contagious viruses and can play a pivotal role in informing the custodians and downstream water users of potential risks embedded in water bodies.


Subject(s)
COVID-19 , Drinking Water , Disease Outbreaks , Humans , SARS-CoV-2 , Waste Water
13.
Sci Total Environ ; 804: 150244, 2022 Jan 15.
Article in English | MEDLINE | ID: covidwho-1525948

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemia has been one of the most difficult challenges humankind has recently faced. Wastewater-based epidemiology has emerged as a tool for surveillance and mitigation of potential viral outbreaks, circumventing biases introduced by clinical patient testing. Due to the situation urgency, protocols followed for isolating viral RNA from sewage were not adapted for such sample matrices. In parallel to their implementation for fast collection of data to sustain surveillance and mitigation decisions, molecular protocols need to be harmonized to deliver accurate, reproducible, and comparable analytical outputs. Here we studied analytical variabilities linked to viral RNA isolation methods from sewage. Three different influent wastewater volumes were used to assess the effects of filtered volumes (50, 100 or 500 mL) for capturing viral particles. Three different concentration strategies were tested: electronegative membranes, polyethersulfone membranes, and anion-exchange diethylaminoethyl cellulose columns. To compare the number of viral particles, different RNA isolation methods (column-based vs. magnetic beads) were compared. The effect of extra RNA purification steps and different RT-qPCR strategies (one step vs. two-step) were also evaluated. Results showed that the combination of 500 mL filtration volume through electronegative membranes and without multiple RNA purification steps (using column-based RNA purification) using two-step RT-qPCR avoided false negatives when basal viral load in sewage are present and yielded more consistent results during the surveillance done during the second-wave in Delft (The Hague area, The Netherlands). By paving the way for standardization of methods for the sampling, concentration and molecular detection of SARS-CoV-2 viruses from sewage, these findings can help water and health surveillance authorities to use and trust results coming from wastewater based epidemiology studies in order to anticipate SARS-CoV-2 outbreaks.


Subject(s)
COVID-19 , Sewage , Humans , RNA, Viral , SARS-CoV-2 , Waste Water , Wastewater-Based Epidemiological Monitoring
14.
PLoS One ; 16(11): e0258263, 2021.
Article in English | MEDLINE | ID: covidwho-1511816

ABSTRACT

Clinical and surveillance testing for the SARS-CoV-2 virus relies overwhelmingly on RT-qPCR-based diagnostics, yet several popular assays require 2-3 separate reactions or rely on detection of a single viral target, which adds significant time, cost, and risk of false-negative results. Furthermore, multiplexed RT-qPCR tests that detect at least two SARS-CoV-2 genes in a single reaction are typically not affordable for large scale clinical surveillance or adaptable to multiple PCR machines and plate layouts. We developed a RT-qPCR assay using the Luna Probe Universal One-Step RT-qPCR master mix with publicly available primers and probes to detect SARS-CoV-2 N gene, E gene, and human RNase P (LuNER) to address these shortcomings and meet the testing demands of a university campus and the local community. This cost-effective test is compatible with BioRad or Applied Biosystems qPCR machines, in 96 and 384-well formats, with or without sample pooling, and has a detection sensitivity suitable for both clinical reporting and wastewater surveillance efforts.


Subject(s)
COVID-19/virology , Ribonuclease P/genetics , SARS-CoV-2/genetics , Waste Water/virology , DNA Primers/genetics , Humans , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/methods , Sensitivity and Specificity , Specimen Handling/methods , Wastewater-Based Epidemiological Monitoring
15.
Sci Total Environ ; 806(Pt 4): 151391, 2022 Feb 01.
Article in English | MEDLINE | ID: covidwho-1504578

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA transmission route was thoroughly investigated in the hospital wastewater, sewage collection network, and wastewater treatment plants. Samples were taken on four occasions from December 2020 to April 2021. The performance of two different wastewater treatment processes of sequencing batch reactor (SBR) and conventional activated sludge (CAS) was studied for virus destruction. For this purpose, liquid phase, solid phase and bioaerosol samples were taken from different units of the investigated wastewater treatment plants (WWTPs). The results revealed that all untreated hospital wastewater samples were positive for SARS-CoV-2 RNA. The virus detection frequency increased when the number of hospitalized cases increased. Detection of viral RNA in the wastewater collection system exhibited higher load of virus in the generated wastewater in areas with poor socioeconomic conditions. Virus detection in the emitted bioaerosols in WWTPs showed that bioaerosols released from CAS with surface aeration contains SARS-CoV-2 RNA posing a potential threat to the working staff of the WWTPs. However, no viral RNA was detected in the bioaerosols of the SBR with diffused aeration system. Investigation of SARS-CoV-2 RNA in WWTPs showed high affinity of the virus to be accumulated in biosolids rather than transporting via liquid phase. Following the fate of virus in sludge revealed that it is completely destructed in anaerobic sludge treatment process. Therefore, based on the results of the present study, it can be concluded that receiving water resources could not be contaminated with virus, if the wastewater treatment processes work properly.


Subject(s)
COVID-19 , Sewage , Humans , RNA, Viral , SARS-CoV-2 , Waste Water
16.
Environ Sci Technol ; 55(22): 15276-15286, 2021 11 16.
Article in English | MEDLINE | ID: covidwho-1503942

ABSTRACT

Wastewater based epidemiology (WBE) has become an important tool during the COVID-19 pandemic, however the relationship between SARS-CoV-2 RNA in wastewater treatment plant influent (WWTP) and cases in the community is not well-defined. We report here the development of a national WBE program across 28 WWTPs serving 50% of the population of Scotland, including large conurbations, as well as low-density rural and remote island communities. For each WWTP catchment area, we quantified spatial and temporal relationships between SARS-CoV-2 RNA in wastewater and COVID-19 cases. Daily WWTP SARS-CoV-2 influent viral RNA load, calculated using daily influent flow rates, had the strongest correlation (ρ > 0.9) with COVID-19 cases within a catchment. As the incidence of COVID-19 cases within a community increased, a linear relationship emerged between cases and influent viral RNA load. There were significant differences between WWTPs in their capacity to predict case numbers based on influent viral RNA load, with the limit of detection ranging from 25 cases for larger plants to a single case in smaller plants. SARS-CoV-2 viral RNA load can be used to predict the number of cases detected in the WWTP catchment area, with a clear statistically significant relationship observed above site-specific case thresholds.


Subject(s)
COVID-19 , Water Purification , Humans , Pandemics , RNA, Viral , SARS-CoV-2 , Viral Load , Waste Water
17.
Water Sci Technol ; 84(12): 3508-3514, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1502205

ABSTRACT

Several studies have detected SARS-CoV-2 in the stool of infected people as in urban wastewater. The quantification of SARS-CoV-2 in wastewater appears today as a powerful tool that can help in wastewater-based epidemiology (WBE). The goal is to improve the prediction of new waves of COVID-19 outbreaks and provide an early warning of the evolution of the infection. In this research, we highlighted some practical and scientific aspects that emerged during an extensive ongoing monitoring campaign carried out on a large number of wastewater treatment plants located in the province of Trento (North Italy) and aimed at the detection of SARS-CoV-2 in raw municipal wastewater. The open issues underline are related to the collection and storage (sampling protocol, storage and heat treatment), to the molecular analysis (enrichment phase), and to the mathematical calculation of SARS-CoV-2 load in wastewater, suitable for WBE (standard curve to obtain the concentration of genomic units and flow rate measurements). This study provides some insights that can help in the implementation of surveillance plans in other regions.


Subject(s)
COVID-19 , Water Purification , Humans , Italy , SARS-CoV-2 , Waste Water
18.
Sci Rep ; 11(1): 21368, 2021 11 01.
Article in English | MEDLINE | ID: covidwho-1493221

ABSTRACT

There is a need for wastewater based epidemiological (WBE) methods that integrate multiple, variously sized surveillance sites across geographic areas. We developed a novel indexing method, Melvin's Index, that provides a normalized and standardized metric of wastewater pathogen load for qPCR assays that is resilient to surveillance site variation. To demonstrate the utility of Melvin's Index, we used qRT-PCR to measure SARS-CoV-2 genomic RNA levels in influent wastewater from 19 municipal wastewater treatment facilities (WWTF's) of varying sizes and served populations across the state of Minnesota during the Summer of 2020. SARS-CoV-2 RNA was detected at each WWTF during the 20-week sampling period at a mean concentration of 8.5 × 104 genome copies/L (range 3.2 × 102-1.2 × 109 genome copies/L). Lag analysis of trends in Melvin's Index values and clinical COVID-19 cases showed that increases in indexed wastewater SARS-CoV-2 levels precede new clinical cases by 15-17 days at the statewide level and by up to 25 days at the regional/county level. Melvin's Index is a reliable WBE method and can be applied to both WWTFs that serve a wide range of population sizes and to large regions that are served by multiple WWTFs.


Subject(s)
COVID-19/epidemiology , SARS-CoV-2/genetics , Suburban Population , Urban Population , Waste Disposal Facilities , Waste Water/virology , Wastewater-Based Epidemiological Monitoring , Water Purification , COVID-19/virology , Genome, Viral , Humans , Minnesota/epidemiology , Prevalence , Prognosis , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction/methods , Risk Factors
19.
Water Environ Res ; 93(11): 2819-2827, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1491014

ABSTRACT

There have been multiple reports of COVID-19 virus, SARS-CoV-2 RNA presence in influent wastewater of water reclamation facilities (WRFs) across the world. In this study, the removal of SARS-CoV-2 RNA was investigated in a WRF by collecting samples from various stages relayed to hydraulic retention time (HRT) and analyzed for viral RNA (N1 and N2) gene markers and wastewater characteristics. SARS-CoV-2 RNA was detected in 28 out of 28 influent wastewater and primary effluent samples. Secondary effluent showed 4 out of 9 positive samples, and all tertiary and final effluent samples were below the detection limit for the viral markers. The reduction was significant (p value < 0.005, one-way analysis of variance [ANOVA] test) in secondary treatment, ranging from 1.4 to 2.0 log10 removal. Adjusted N1 viral marker had a positive correlation with total suspended solids, total Kjeldahl nitrogen, and ammonia concentrations (Spearman's ρ = 0.61, 0.67, and 0.53, respectively, p value < 0.05), while demonstrating a strongly negative correlation with HRT (Spearman's ρ = -0.58, p value < 0.01). PRACTITIONER POINTS: Viral RNA was present in all samples taken from influent and primary effluent of a WRF. SARS-CoV-2 gene marker was detected in secondary effluent in 4 out of 9 samples. Tertiary and final effluent samples tested nondetect for SARS-CoV-2 gene markers. Up to 0.5 and 2.0 log10 virus removal values were achieved by primary and secondary treatment, respectively.


Subject(s)
COVID-19 , Water Purification , Biomarkers , Humans , RNA, Viral , SARS-CoV-2 , Waste Water , Water
20.
Environ Sci Technol ; 55(17): 12009-12018, 2021 09 07.
Article in English | MEDLINE | ID: covidwho-1483072

ABSTRACT

Diatrizoate, a refractory ionic iodinated X-ray contrast media (ICM) compound, cannot be efficiently degraded in a complex wastewater matrix even by advanced oxidation processes. We report in this research that a homogeneous process, thiourea dioxide (TDO) coupled with trace Cu(II) (several micromoles, ubiquitous in some wastewater), is effective for reductive deiodination and degradation of diatrizoate at neutral pH values. Specifically, the molar ratio of iodide released to TDO consumed reached 2 under ideal experimental conditions. TDO eventually decomposed into urea and sulfite/sulfate. Based on the results of diatrizoate degradation, TDO decomposition, and Cu(I) generation and consumption during the TDO-Cu(II) reaction, we confirmed that Cu(I) is responsible for diatrizoate degradation. However, free Cu(I) alone did not work. It was proposed that Cu(I) complexes are actual reactive species toward diatrizoate. Inorganic anions and effluent organic matter negatively influence diatrizoate degradation, but by increasing the TDO dosage, as well as extending the reaction time, its degradation efficiency can still be guaranteed for real hospital wastewater. This reduction reaction could be potentially useful for in situ deiodination and degradation of diatrizoate in hospital wastewater before discharge into municipal sewage networks.


Subject(s)
Diatrizoate , Water Pollutants, Chemical , Contrast Media , Oxidation-Reduction , Thiourea/analogs & derivatives , Waste Water , Water Pollutants, Chemical/analysis
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