A systematic review on the occurrence, fate, and remediation of SARS-CoV-2 in wastewater.

The COVID-19 has been declared a pandemic by the World Health Organization. Along with impairing the respiratory system, it also affects the gastrointestinal system. By reviewing experiments on the wastewater analysis for the detection of coronavirus, this study explores the fate, persistence, and various remediation strategies for the virus removal from the wastewater. The results indicated that the virus can be detected in the wastewater samples, feces, and sewage, even before the onset of symptoms. Coronavirus can be a potential panzootic disease, as several mammalian species get infected by the deadly virus. The disinfection strategies used earlier for the treatment of wastewater are not sufficient for the removal of viruses from the wastewater. Therefore, concerted efforts should be made to understand their fate, sources, and occurrence in the environmental matrices. To prevent the spread of the panzootic disease, revised guidelines should be issued for the remediation of the virus. Recent viral remediation methods such as membrane bioreactors and advanced oxidation methods can be used. Therefore, the present review puts a light on the current knowledge on the occurrence of coronaviruses in wastewater, the possible sources, fate, and removal strategies.

Antiviral drugs in wastewater are on the rise as emerging contaminants: A comprehensive review of spatiotemporal characteristics, removal technologies and environmental risks.

Antiviral drugs (ATVs) are widely used to treat illnesses caused by viruses. Particularly, ATVs were consumed in such large quantities during the pandemic that high concentrations were detected in wastewater and aquatic environment. Since ATVs are not fully absorbed by the human or animal body, this results in large amounts of them being discharged into the sewage through urine or feces. Most ATVs can be degraded by microbes at wastewater treatment plants (WWTPs), while some ATVs either require deep treatment to reduce concentration and toxicity. Parent and metabolites residing in effluent posed a varying degree of risk when entering the aquatic environment, while increasing the potential of natural reservoirs for environmentally acquired antiviral drug resistance potential. There is a rising research on the behavior of ATVs in the environment has surged since the pandemic. In the context of multiple viral diseases worldwide, especially during the current COVID-19 pandemic, a comprehensive assessment of the occurrence, removal, and risk of ATVs is urgently needed. This review aims to discuss the fate of ATVs in WWTPs from various regions in the world with wastewater as the main analyzing object. The ultimate goal is to focus on ATVs with high ecological impact and regulate their use or develop advanced treatment technologies to mitigate the risk to the environment.

Wastewater-Based Epidemiology of SARS-CoV-2: Assessing Prevalence and Correlation with Clinical Cases.

Wastewater-based epidemiology has been recognized as a tool to monitor the progress of COVID-19 pandemic worldwide. The study presented herein aimed at quantitating the SARS-CoV-2 RNA in the wastewaters, predicting the number of infected individuals in the catchment areas, and correlating it with the clinically reported COVID-19 cases. Wastewater samples (n = 162) from different treatment stages were collected from three wastewater treatment plants (WWTPs) from Mumbai city during the 2nd surge of COVID-19 (April 2021 to June 2021). SARS-CoV-2 causing COVID-19, was detected in 76.2% and 4.8% of raw and secondary treated (n = 63 each) wastewater samples respectively while all tertiary treated samples (n = 36) were negative. The quantity of SARS-CoV-2 RNA determined as gene copies/100 mL varied among all the three WWTPs under study. The gene copy numbers thus obtained were further used to estimate the number of infected individuals within the population served by these WWTPs using two published methods. A positive correlation (p < 0.05) was observed between the estimated number of infected individuals and clinically confirmed COVID-19 cases reported during the sampling period in two WWTPs. Predicted infected individuals calculated in this study were 100 times higher than the reported COVID-19 cases in all the WWTPs assessed. The study findings demonstrated that the present wastewater treatment technologies at the three WWTPs studied were adequate to remove the virus. However, SARS-CoV-2 genome surveillance with emphasis on monitoring its variants should be implemented as a routine practice to prepare for any future surge in infections.

Antibiotic resistomes in face-mask biofilm along an urban river: Multiple drivers and co-occurrence with human opportunistic pathogens.

Discarded face masks from the global COVID-19 pandemic have contributed significantly to plastic pollution in surface water, whereas their potential as a reservoir for aquatic pollutants is not well understood. Herein, we conducted a field experiment along a human-impacted urban river, investigating the variations of antibiotic resistance genes (ARGs), pathogens, and water-borne contaminants in commonly-used face masks. Results showed that high-biomass biofilms formed on face masks selectively enriched more ARGs than stone biofilm (0.08-0.22 vs 0.07-0.15 copies/16 S rRNA gene copies) from bulk water, which mainly due to unique microbial communities, enhanced horizontal gene transfer, and selective pressure of accumulated contaminants based on redundancy analysis and variation partitioning analysis. Several human opportunistic pathogens (e.g., Acinetobacter, Escherichia-Shigella, Bacillus, and Klebsiella), which are considered potential ARG carriers, were also greatly concentrated in face-mask biofilms, imposing a potential threat to aquatic ecological environment and human health. Moreover, wastewater treatment plant effluents, as an important source of pollutants to urban rivers, further aggravated the abundances of ARGs and opportunistic pathogens in face-mask biofilms. Our findings demonstrated that discarded face masks provide a hotspot for the proliferation and spread of ARGs and pathogens in urban water, highlighting the urgent requirement for implementing stricter regulations in face mask disposal.

Monitoring of the Surfactants in Surface Waters in Slovakia and the Possible Impact of COVID-19 Pandemic on Their Presence

In order to keep the home and occupational environment clean and non-infectious, the consumption of cleaners and disinfectants, including cosmetics, is increasing. Excessive use of these products results in their accumulation in the aquatic environment. Conventional wastewater treatment plants are unable to effectively remove the emergent pollutants, including personal care products. This article is focused on the monitoring of the presence of personal care products in surface waters in two river basins in the Slovak Republic, in terms of the surfactant content. Ecotoxicological evaluation of the selected samples from the monitored river basins was performed by an acute toxicity test using the test organism Daphnia magna. The monitoring results indicate the presence of personal care products in the aquatic environment which poses an ecological and environmental risk. Monitoring in the Hron and Nitra river basins confirmed contamination with the surfactants, to which the measures related to the COVID-19 pandemic contributed. The content of the surfactants in personal care products is significant, and their impact on the aquatic environment is not sufficiently monitored.

SARS-CoV-2 in the environment: Contamination routes, detection methods, persistence and removal in wastewater treatment plants.

The present study reviewed the occurrence of SARS-CoV-2 RNA and the evaluation of virus infectivity in feces and environmental matrices. The detection of SARS-CoV-2 RNA in feces and wastewater samples, reported in several studies, has generated interest and concern regarding the possible fecal-oral route of SARS-CoV-2 transmission. To date, the presence of viable SARS-CoV-2 in feces of COVID-19 infected people is not clearly confirmed although its isolation from feces of six different patients. Further, there is no documented evidence on the infectivity of SARS-CoV-2 in wastewater, sludge and environmental water samples, although the viral genome has been detected in these matrices. Decay data revealed that SARS-CoV-2 RNA persisted longer than infectious particle in all aquatic environment, indicating that genome quantification of SARS-CoV-2 does not imply the presence of infective viral particles. In addition, this review also outlined the fate of SARS-CoV-2 RNA during the different steps in the wastewater treatment plant and focusing on the virus elimination along the sludge treatment line. Studies showed complete removal of SARS-CoV-2 during the tertiary treatment. Moreover, thermophilic sludge treatments present high efficiency in SARS-CoV-2 inactivation. Further studies are required to provide more evidence with respect to the inactivation behavior of infectious SARS-CoV-2 in different environmental matrices and to examine factors affecting SARS-CoV-2 persistence.

Progress in the distribution characteristics and risks of bioaerosols from anthropogenic sources

In recent years, the global outbreak of COVID-19 has aroused public attention to the potential risks of bioaerosols and the studies about the potential health hazards of bioaerosols from anthropogenic sources have been increasing. We introduced the research status of four main anthropogenic bioaerosols in recent years, compared the distribution and composition characteristics of bioaerosols from different anthropogenic sources, and analyzed the main factors affecting the characteristics and potential risks of bioaerosols. The average concentration of bioaerosol is high in animal farms, moderate in wastewater treatment plants and landfills, and low in hospitals. The microbial composition of bioaerosols at different sites is closely associated with the bioaerosol source and affected by the environmental conditions. Furthermore, this work prospected the main research directions of anthropogenic bioaerosols in the future, aiming to lay a foundation for the establishment of bioaerosol control standards and the development of control technology.

Impact of Coronavirus spread prevention actions on sewage quantity and quality

Spread prevention actions (SPAs) during Coronavirus pandemic period, such as increased hand-washing, temporary lock-downs, preventions in transportation, and the reduction of recreational and industrial activities may change the routines in social behaviors. Accordingly, SPAs can be effective on the quality and quantity of raw municipal wastewater. This research evaluates the aforementioned hypothesis and recommends solutions for the proper operation of wastewater treatment plants (WWTPs). Methods: For this purpose, the quantity and quality of sewage in 23 municipal WWTPs in Isfahan province, as the study area, were surveyed and compared from 2015 to 2020. SPSS software (version 23) was used for statistical analysis. Results: Results indicated that the annual growth rate of sewage discharged in the spring and summer of 2020 (period of SPAs) in the study area is 24% more than the average of annual growth rate in long-term (2015-2019). This increase is 45% in small WWTPs, while it is only 5% in large WWTPs. Results also revealed that the concentration of chemical oxidation demand (COD) of sewage was reduced 24% on average in this period. In addition, the biodegradability of wastewater is increased in large WWTPs mainly due to the decrease of industrial activities. Conclusion: Therefore, SPAs in the pandemic period of Coronavirus could increase the quantity of municipal wastewater and reduce its COD concentrations. These variations may provide more appropriate operational conditions for waste stabilization ponds rather than activated sludge units.

SARS-CoV-2 RNA abundance in wastewater as a function of distinct urban sewershed size

During the COVID-19 pandemic, wastewater-based epidemiology has emerged as a promising approach for monitoring SARS-CoV-2 prevalence on a community-level. Despite much being known about the utility of making these measurements in large wastewater treatment plants, little is known about the correlation with finer geographic resolution, such as those obtained through sewershed sub-area catchments. This study aims to identify community wastewater surveillance characteristics between sewershed areas that affect the strength of the association of SARS-CoV-2 RNA detection in a metropolitan area. For this, wastewater from 17 sewershed areas were sampled in Louisville/Jefferson County, Kentucky (USA), from August 2020 to April 2021 (N = 727), which covered approximately 97% of the county's households. Solids were collected from the treatment plants from November 2020 to December 2020 (N = 42). Our results indicate that the sewersheds differ in SARS-CoV-2 trends;however, high pairwise correlation spatial trends were not observed, and the mean SARS-CoV-2 RNA concentrations of smaller upstream community sewershed areas did not differ from their respective treatment centers. Solid samples could only be collected at treatment plants, therefore not allowing us to evaluate SARS-CoV-2 abundance as a function of the sewershed scale. The population size sensitivity of SARS-CoV-2 concentration detection is non-linear: at low population levels the measures are either too sensitive and generate a high level of variability, or at high population levels the estimates are dampened making small changes in community infection levels more difficult to discern. Our results suggest selecting sampling sites that include a wide population range. This study and its findings may inform other system-wide strategies for sampling wastewater for estimating non-SARS-CoV-2 targets.

Consequence of COVID-19 occurrences in wastewater with promising recognition and healing technologies: A review.

Presently, the coronavirus (COVID-19) epidemic presents a major threat to global communal fitness also socio-financial development. Ignoring worldwide isolation as well as shutdown attempts, the occurrence of COVID-19 infected patients continues to be extremely large. Nonetheless, COVID-19's final course, combined with the prevalence of emerging contaminants (antibiotics, pharmaceuticals, nanoplastics, pesticides, and so forth) in wastewater treatment plants (WWTPs), presents a major problem in wastewater situations. The research, therefore, intends near examine an interdisciplinary as well as technical greet to succor COVID-19 with subsequent COVID cycles of an epidemic as a framework for wastewater treatment settings. This research investigated the potential for wastewater-based epidemiology to detect SARS-CoV-2 also the enzymes happening in wastewater conditions. In addition, a chance for the incorporation into the WWTPs of emerging and robust technologies such as mesmeric nanobiotechnology, electrochemical oxidation, microscopy, and membrane processes to enhance the overall likelihood of environmental consequences of COVID-19 also strengthen such quality of water is resolved.

The effect of disinfectants and antiseptics on co- and cross-selection of resistance to antibiotics in aquatic environments and wastewater treatment plants.

The outbreak of the SARS-CoV-2 pandemic led to increased use of disinfectants and antiseptics (DAs), resulting in higher concentrations of these compounds in wastewaters, wastewater treatment plant (WWTP) effluents and receiving water bodies. Their constant presence in water bodies may lead to development and acquisition of resistance against the DAs. In addition, they may also promote antibiotic resistance (AR) due to cross- and co-selection of AR among bacteria that are exposed to the DAs, which is a highly important issue with regards to human and environmental health. This review addresses this issue and provides an overview of DAs structure together with their modes of action against microorganisms. Relevant examples of the most effective treatment techniques to increase the DAs removal efficiency from wastewater are discussed. Moreover, insight on the resistance mechanisms to DAs and the mechanism of DAs enhancement of cross- and co-selection of ARs are presented. Furthermore, this review discusses the impact of DAs on resistance against antibiotics, the occurrence of DAs in aquatic systems, and DA removal mechanisms in WWTPs, which in principle serve as the final barrier before releasing these compounds into the receiving environment. By recognition of important research gaps, research needs to determine the impact of the majority of DAs in WWTPs and the consequences of their presence and spread of antibiotic resistance were identified.

Using Wastewater Surveillance to Compare COVID-19 Outbreaks during the Easter Holidays over a 2-Year Period in Cape Town, South Africa.

Wastewater surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has shown to be an important approach to determine early outbreaks of infections. Wastewater-based epidemiology (WBE) is regarded as a complementary tool for monitoring SARS-CoV-2 trends in communities. In this study, the changes in the SARS-CoV-2 RNA levels in wastewater during Easter holidays in 2021 and 2022 in the City of Cape Town were monitored over nine weeks. Our findings showed a statistically significant difference in the SARS-CoV-2 RNA viral load between the study weeks over the Easter period in 2021 and 2022, except for study week 1 and 4. During the Easter week, 52% of the wastewater treatment plants moved from the lower (low viral RNA) category in 2021 to the higher (medium to very high viral RNA) categories in 2022. As a result, the median SARS-CoV-2 viral loads where higher during the Easter week in 2022 than Easter week in 2021 (p = 0.0052). Mixed-effects model showed an association between the SARS-CoV-2 RNA viral loads and Easter week over the Easter period in 2021 only (p < 0.01). The study highlights the potential of WBE to track outbreaks during the holiday period.

Occurrence, transformation, bioaccumulation, risk and analysis of pharmaceutical and personal care products from wastewater: a review.

Almost all aspects of society from food security to disease control and prevention have benefited from pharmaceutical and personal care products, yet these products are a major source of contamination that ends up in wastewater and ecosystems. This issue has been sharply accentuated during the coronavirus disease pandemic 2019 (COVID-19) due to the higher use of disinfectants and other products. Here we review pharmaceutical and personal care products with focus on their occurrence in the environment, detection, risk, and removal. Supplementary Information: The online version contains supplementary material available at 10.1007/s10311-022-01498-7.

Influent Fluctuation Analysis and Operation Strategy of Wastewater Treatment Plants during Shanghai's City-wide Lockdown Period

The city-wide lockdown management was implemented in Shanghai from the end of March to the beginning of June in response to the prevention and control of COVID-19 epidemic. The sudden change of the way of work, lifestyle and industrial structure in the megacity would inevitably influence the characteristics of wastewater production, the composition of wastewater, the influent conditions, and operations of wastewater treatment plants（WWTPs）. The main countermeasures of operation in typical WWTPs were analyzed, which could provide a reference for early-warning and precaution when similar situations occur in WWTPs in the future. In order to eliminate the interference caused by the hysteresis effect after the rain stops in the combined drainage system, the corresponding relationship between the rainfall conditions and the influent quantity and quality of WWTPs was studied.The new statistical standard was established for distinguishing"rainy days"or"count dry days". The contemporaneous data of WWTPs in Shanghai central area during dry season in the past three years was analyzed. It was found that the quantity and quality of the influent showed a reverse trend during Shanghai's city-wide lockdown period. The quantity of wastewater decreased by 6% in the corresponding period, and the concentration of COD and NH3-N decreased by 33% and 17%, respectively. The addition of a large amount of chlorine-containing disinfectants led to an increase in the concentration of residual chlorine in the influent of some WWTPs. Based on the analysis of treatment process and design parameters of the existing WWTPs, the operation mode of exploiting potentialities was finally adopted.WWTPs operated stably and the effluent quality could meet the discharge standards through measures such as strengthening pretreatment, prolonging sludge retention time, controlling the concentration of dissolved oxygen in the biological reaction section, and increasing the dosage of phosphorus removal agents.

Industrial Wastewater Discharge and Compliance Investigation for Environmentally Resilient Rwanda

While Rwanda is aiming at environmental pollution resilience and green growth, some industries are still discharging untreated effluent into the environment. This study gives a general overview of the compliance level of industrial effluent discharge in Rwanda and the linked negative environmental impacts. It comprises qualitative and quantitative analyses of data obtained from wastewater samples collected from five selected industries in Rwanda. The selected industries had previously been audited and monitored by the Rwanda Environment Management Authority (REMA), due to complains from neighboring residents. The study found that the effluent discharge from wastewater treatment plants (WWTP) for all concerned industries failed to comply with (i) oil and grease (O&G) national and international tolerable parameter limits or the (ii) fecal coliforms national standard. In addition, a compliance level of 66.7% was observed for key water quality monitoring parameters (pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and heavy metals (i.e., lead (Pb), cadmium (Cd), and chromium (Cr)). Following these study findings, one industry was closed by the REMA for deliberately discharging untreated effluent into an adjacent river. This study recommends the adoption of the best available technology for effluent treatment, installation or renovation of existing WWTPs, and the relocation to industrial zones of industries adjacent to fragile environments.

Utjecaj pandemije 2020. godine na rezultate analize potreba za vodom i posljedično definiranje količina otpadnih voda i kapaciteta UPOV-a

S ciljem suzbijanja globalne pandemije bolesti COVID-19 tijekom 2020. godine uvedene su stroge mjere koje su ograničavale brojne aktivnosti, djelatnosti i kretanje stanovništva na razini cijelog Svijeta pa tako i Hrvatske. U ovom radu analiziran je utjecaj uvedenih ograničenja na kretanje potrošnje vode po pojedinim kategorijama potrošača (kućanstva, privreda) na temelju podataka prikupljenih za 17 isporučitelja vodnih usluga na području Republike Hrvatske. Pritom su podjednako zastupljeni podaci za kontinentalni (ne-turistički) i primorski (turistički orijentiran) dio teritorija. Provedena je analiza potrošnje vode u 2020. godini u odnosu na prosječne vrijednosti potrošnje u prethodnom petogodišnjem periodu. Detektirane su promjene u odnosu na udio pojedine kategorije u ukupnoj potrošnji te su dani zaključci i preporuke o potrebi kritičkog sagledavanja podataka za 2020. godinu prilikom izrade projekcija u sklopu analize potreba za vodom. Na pokaznom primjeru demonstriran je i utjecaj promjena u potrošnji vode 2020. godine na definiranje opterećenja (hidrauličkog i biološkog) uređaja za pročišćavanje otpadnih voda.Alternate :In order to supress the COVID-19 global pandemics in 2020, strict measures, which limited numerous activities and movement of people at the global level, including Croatia, were introduced. The paper analyses the impact of introduced limitations on the water demand per individual consumer categories (households, economy) based on data collected for 17 water services providers in the Republic of Croatia. The data for the continental and coastal (tourism-oriented) parts of the country were equally represented. The conducted analysis looked at water consumption in 2020 in relation to average consumption values in the previous 5-year period. The changes regarding the shares of individual categories in the total consumption were detected, and conclusions and recommendations were offered in relation to the need for gaining a critical insight into the 2020 data when developing projections within the water demand analysis. An indicative example was also used as a demonstration of the impact of changes in the 2020 water consumption on the determination of (hydraulic and biological) loads on waste water treatment plants.Alternate :Im Laufe des Jahres 2020 wurden strenge Maßnahmen getroffen, die zahlreiche Aktivitäten, Tätigkeiten und Bewegungsfreiheit der Bevölkerung in der ganzen Welt und so auch in Kroatien beschränkt haben mit dem Ziel, die COVID-19-Pandemie zu bekämpfen. In diesem Beitrag wird der Einfluss der eingeführten Beschränkungen auf den Wasserverbrauch in einzelnen Verbraucherkategorien (Haushalte, Industrie) analysiert auf Grund der Angaben, die von 17 Wasserversorgern in Kroatien erhoben wurden. Dabei werden die Angaben für das kontinentale Gebiet (nicht-touristisch orientiert) und die Küste (touristisch orientiert) gleichermaßen vertreten. Die Analyse des Wasserverbrauchs im Jahre 2020 wurde in Vergleich zu den durchschnittlichen Werten im vergangenen Fünfjahreszeitraum durchgeführt. Es konnten Änderungen in Bezug auf den Anteil einzelner Kategorie im Gesamtverbrauch festgestellt werden. Die Ergebnisse und Empfehlungen für die Notwendigkeit einer kritischen Betrachtung dieser Angaben für 2020 werden angesichts der Erfassung von Projektionen im Rahmen der Wasserbedarfsanalysen gegeben. Auf einem Beispiel wird auch der Einfluss der Änderungen im Wasserverbrauch in 2020 auf die Bestimmung der hydraulischen und biologischen Belastung einer Abwasserkläranlage dargestellt.

A critical review on the existing wastewater treatment methods in the COVID-19 era: What is the potential of advanced oxidation processes in combatting viral especially SARS-CoV-2?

The COVID-19 epidemic has put the risk of virus contamination in water bodies on the horizon of health authorities. Hence, finding effective ways to remove the virus, especially SARS-CoV-2, from wastewater treatment plants (WWTPs) has emerged as a hot issue in the last few years. Herein, this study first deals with the fate of SARS-CoV-2 genetic material in WWTPs, then critically reviews and compares different wastewater treatment methods for combatting COVID-19 as well as to increase the water quality. This critical review sheds light the efficiency of advanced oxidation processes (AOPs) to inactivate virus, specially SARS-CoV-2 RNA. Although several physicochemical treatment processes (e.g. activated sludge) are commonly used to eliminate pathogens, AOPs are the most versatile and effective virus inactivation methods. For instance, TiO2 is the most known and widely studied photo-catalyst innocuously utilized to degrade pollutants as well as to photo-induce bacterial and virus disinfection due to its high chemical resistance and efficient photo-activity. When ozone is dissolved in water and wastewater, it generates a wide spectrum of the reactive oxygen species (ROS), which are responsible to degrade materials in virus membranes resulting in destroying the cell wall. Furthermore, electrochemical advanced oxidation processes act through direct oxidation when pathogens react at the anode surface or by indirect oxidation through oxidizing species produced in the bulk solution. Consequently, they represent a feasible choice for the inactivation of a wide range of pathogens. Nonetheless, there are some challenges with AOPs which should be addressed for application at industrial-scale.

Occurrence and distribution of azithromycin in wastewater treatment plants, seawater, and sediments of the northern part of the Persian Gulf around Bushehr port: A comparison with Pre-COVID 19 pandemic.

One of the environmental effects of COVID 19 is the contamination of ecosystems with antibiotics due to their high consumption to treat this disease. Many years ago, the distribution of antibiotics including azithromycin (Azi) in wastewater treatment plants in Bushehr city, seawater, and sediment of the Persian Gulf has been investigated. As Azi has been prescribed to COVID 19 patients, contamination of the environment with this drug can also be assumed. Thus, we decided to examine this hypothesis by repeating our previous study during COVID 19 period. We collected wastewater samples from influent, effluent, and different units of three wastewater treatment plants (WWTPs) including one municipal WWTP (Plant A) and two hospital-WWTPs (Plant B and C). Seawater and adjusted sediments were gathered from 8 stations located in the Persian Gulf in two seasons to evaluate the special and temporal variation. The results showed a huge growth of Azi pollution in all studied matrixes. The mean Azi values in the influent of Plant A, B, and C were 145 ng/L, 110 ng/L, and 896 ng/L, which represented an 9, 6, and 48-time increase compared with those obtained in 2017 (before COVID 19). The Azi removal efficiency had a different behavior compared to before COVID 19. The mean concentration of Azi in seawater and sediment samples was 9 ng/L and 6 ng/g, which was 3 and 4-fold higher than the previous study. Opposed to our former study, the Azi amount in the aqueous phase was less subjected to temporal seasonal variations. Our observations indicated the wide distribution of Azi in the environment and a future threat of intense growth of antibiotic resistance in ecosystems.

Neighbourhood-scale wastewater-based epidemiology for COVID-19: opportunities and challenges

Auckland is New Zealand's largest city and is the main international entry point to New Zealand, with most of the nation's Managed Isolation and Quarantine Facilities. Consequently, it is the place most likely for a COVID-19 outbreak to occur and, accordingly, has been the focus of efforts to monitor SARS-CoV-2 via wastewater-based epidemiology. Historically, wastewater-based epidemiology has mainly been applied at the catchment or sewershed scale, with samples collected at wastewater treatment plants. COVID-19 has necessitated a re-evaluation of this broad-scale approach to wastewaterbased epidemiology in New Zealand, where there is a need for more detailed information to better target the public health response. Using Auckland as a case study, this paper assesses the spatial and temporal extent of the city's wastewater network to inform the selection of strategic neighbourhoodscale sampling sites for wastewater-based epidemiology. Sample site selection criteria included topology and connectivity of the sewer network, the capacity to record sewer flow, limited rain infiltration, resident population, and accessibility. Six sites were identified that provide an immediate opportunity for neighbourhood-scale monitoring. Reflecting on the analysis required for selecting appropriate monitoring locations, the paper moves to critically discuss the key unknowns and research needs associated with conducting neighbourhoodscale wastewater-based epidemiology. Population mobility poses challenges for estimating population size and for capturing a positive SARS-CoV-2 signal in wastewater at this scale. There is a need to determine the full spectrum of residence times within the sewer network to design representative sampling and the implications of disregarding residence times in the current sampling regimes are poorly understood. Hydraulic models require refinement to accurately account for variable residence times and topological features in the network (e.g., holding tanks and pumping stations). Addressing these challenges is urgent and ongoing to realise the benefits of neighbourhood-scale wastewater-based epidemiology in response to COVID-19 and beyond.

Molecular Monitoring of SARS-CoV-2 in Different Sewage Plants in Venice and the Implications for Genetic Surveillance

Wastewater-based epidemiology is now widely used as an indirect tool to monitor the spread of SARS-CoV-2. In this study, five different sample matrices representing diverse phases of the wastewater treatment process were collected during the second wave of SARS-CoV-2 from two wastewater treatment plants (WWTPs) serving the Civil Hospital and Sacca Fisola island in Venice, Italy. Positive SARS-CoV-2 detections occurred at both WWTPs, and data on viral genome detection rate and quantification suggest that the pellet (i.e., the particulate resulting from the influent) is a sensitive matrix that permits reliable assessment of infection prevalence while reducing time to results. On the contrary, analysis of post-treatment matrices provides evidence of the decontamination efficacy of both WWTPs. Finally, direct sequencing of wastewater samples enabled us to identify B.1.177 and B.1.160 as the prevalent SARS-CoV-2 lineages circulating in Venice at the time of sampling. This study confirmed the suitability of wastewater testing for studying SARS-CoV-2 circulation and established a simplified workflow for the prompt detection and characterization of the virus.