SARS-CoV-2 in river water: Implications in low sanitation countries

COVID-19 surveillance in wastewater: An epidemiological tool for the monitoring of SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic has prompted a lot of questions globally regarding the range of information about the virus's possible routes of transmission, diagnostics, and therapeutic tools. Worldwide studies have pointed out the importance of monitoring and early surveillance techniques based on the identification of viral RNA in wastewater. These studies indicated the presence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in human feces, which is shed via excreta including mucus, feces, saliva, and sputum. Subsequently, they get dumped into wastewater, and their presence in wastewater provides a possibility of using it as a tool to help prevent and eradicate the virus. Its monitoring is still done in many regions worldwide and serves as an early "warning signal"; however, a lot of limitations of wastewater surveillance have also been identified.

Assessment of SARS-CoV-2 Stability in human and environmental matrices, and potential hazards

In the context of the ongoing pandemic of COVID-19, SARS-CoV-2 was detected in human excreta and environmental matrices. The occurrence of SARS-CoV-2 in environmental compartments raises questions on its fate and stability in these matrices and its potential to spread in the exposed communities. This review focused on the stability of the SARS-CoV-2 in human excreta, wastewater, soils, crops, and other environmental matrices, that may be reached through human excreta and sewage products spreading. Little is known about the persistence and survival of SARS-CoV-2 in the environment. Up to now sewage sludge, soil and crops are seldom investigated implying the convenience of considering future researches focusing on SARS-CoV-2 in soils receiving wastewater and sewage sludge, as well as on grown crops. Information regarding SARS-CoV-2 persistence in environmental media is crucial to establish and implement effective policies and measures for mitigating the transmission of COVID-19 and tackling eventual future outbreaks.

Occurrence of SARS-CoV-2 in excreta, sewage, and environment: epidemiological significance and potential risks

The detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in patients' excreta raises the issue of its occurrence and fate in sewage. This review has focused on the presence of the SARS-CoV-2 in human excreta, wastewater, sewage sludge, and river waters. It explored the potential use of the wastewater-based epidemiology approach to report on the situation of current and eventual future SARS-CoV-2 outbreaks. The main concern of the occurrence of SARS-CoV-2 in the environment is the public health risks at sites of sewage products disposal and reuse, especially in low-income countries with inadequate sanitation, where direct discharge and reuse of raw sewage are common practices. The review also addressed the role sewage-irrigated agriculture can have in SARS-CoV-2 spread in the environmental compartments reached through sewage products application. An overview was made on the interest of sewage management, water safety, and hygienic practices for controlling the environmental dissemination of SARS-CoV-2.

SARS-CoV-2 and wastewater: What does it mean for non-human primates?

In most of our lifetimes, we have not faced a global pandemic such as the novel coronavirus disease 2019. The world has changed as a result. However, it is not only humans who are affected by a pandemic of this scale. Our closest relatives, the non-human primates (NHPs) who encounter researchers, sanctuary/zoo employees, and tourists, are also potentially at risk of contracting the virus from humans due to similar genetic susceptibility. "Anthropozoonosis"-the transmission of diseases from humans to other species-has occurred historically, resulting in infection of NHPs with human pathogens that have led to disastrous outbreaks. Recent studies have assessed the susceptibility of NHPs and predict that catarrhine primates and some lemurs are potentially highly susceptible to infection by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. There is accumulating evidence that a new factor to consider with the spread of the virus is fecal-oral transmission. The virus has been detected in the watersheds of countries with underdeveloped infrastructure where raw sewage enters the environment directly without processing. This may expose NHPs, and other animals, to SARS-CoV-2 through wastewater contact. Here, we address these concerns and discuss recent evidence. Overall, we suggest that the risk of transmission of SARS-CoV-2 via wastewater is low. Nonetheless, tracking of viral RNA in wastewater does provide a unique testing approach to help protect NHPs at zoos and wildlife sanctuaries. A One Health approach going forward is perhaps the best way to protect these animals from a novel virus, the same way that we would protect ourselves.

Methods Evaluation for Rapid Concentration and Quantification of SARS-CoV-2 in Raw Wastewater Using Droplet Digital and Quantitative RT-PCR

Wastewater surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging public health tool to understand the spread of Coronavirus Disease 2019 (COVID-19) in communities. The performance of different virus concentration methods and PCR methods needs to be evaluated to ascertain their suitability for use in the detection of SARS-CoV-2 in wastewater. We evaluated ultrafiltration and polyethylene glycol (PEG) precipitation methods to concentrate SARS-CoV-2 from sewage in wastewater treatment plants and upstream in the wastewater network (e.g., manholes, lift stations). Recovery of viruses by different concentration methods was determined using Phi6 bacteriophage as a surrogate for enveloped viruses. Additionally, the presence of SARS-CoV-2 in all wastewater samples was determined using reverse transcription quantitative PCR (RT-qPCR) and reverse transcription droplet digital PCR (RT-ddPCR), targeting three genetic markers (N1, N2 and E). Using spiked samples, the Phi6 recoveries were estimated at 2.6-11.6% using ultrafiltration-based methods and 22.2-51.5% using PEG precipitation. There was no significant difference in recovery efficiencies (p < 0.05) between the PEG procedure with and without a 16 h overnight incubation, demonstrating the feasibility of obtaining same day results. The SARS-CoV-2 genetic markers were more often detected by RT-ddPCR than RT-qPCR with higher sensitivity and precision. While all three SARS-CoV-2 genetic markers were detected using RT-ddPCR, the levels of E gene were almost below the limit of detection using RT-qPCR. Collectively, our study suggested PEG precipitation is an effective low-cost procedure which allows a large number of samples to be processed simultaneously in a routine wastewater monitoring for SARS-CoV-2. RT-ddPCR can be implemented for the absolute quantification of SARS-CoV-2 genetic markers in different wastewater matrices.

Pandemic danger to the deep: The risk of marine mammals contracting SARS-CoV-2 from wastewater

We are in unprecedented times with the ongoing COVID-19 pandemic. The pandemic has impacted public health, the economy and our society on a global scale. In addition, the impacts of COVID-19 permeate into our environment and wildlife as well. Here, we discuss the essential role of wastewater treatment and management during these times. A consequence of poor wastewater management is the discharge of untreated wastewater carrying infectious SARS-CoV-2 into natural water systems that are home to marine mammals. Here, we predict the susceptibility of marine mammal species using a modelling approach. We identified that many species of whale, dolphin and seal, as well as otters, are predicted to be highly susceptible to infection by the SARS-CoV-2 virus. In addition, geo-mapping highlights how current wastewater management in Alaska may lead to susceptible marine mammal populations being exposed to the virus. Localities such as Cold Bay, Naknek, Dillingham and Palmer may require additional treatment of their wastewater to prevent virus spillover through sewage. Since over half of these susceptibility species are already at risk worldwide, the release of the virus via untreated wastewater could have devastating consequences for their already declining populations. For these reasons, we discuss approaches that can be taken by the public, policymakers and wastewater treatment facilities to reduce the risk of virus spillover in our natural water systems. Thus, we indicate the potential for reverse zoonotic transmission of COVID-19 and its impact on marine wildlife; impacts that can be mitigated with appropriate action to prevent further damage to these vulnerable populations.

Coronavirus 2 (SARS-CoV-2) in water environments: Current status, challenges and research opportunities

The outbreak of COVID-19 has posed enormous health, social, environmental and economic challenges to the entire human population. Nevertheless, it provides an opportunity for extensive research in various fields to evaluate the fate of the crisis and combat it. The apparent need for imperative research in the biological and medical field is the focus of researchers and scientists worldwide. However, there are some new challenges and research opportunities in the field of water and wastewater treatment concerning the novel coronavirus 2 (SARS-CoV-2). This article briefly summarizes the latest literature reporting the presence of SARS-CoV-2 in water and wastewater/sewage. Furthermore, it highlights the challenges, potential opportunities and research directions in the water and wastewater treatment field. Some of the significant challenges and research opportunities are the development of standard techniques for the detection and quantification of SARS-CoV-2 in the water phase, assessment of favorable environments for its survival and decay in water; and development of effective strategies for elimination of the novel virus from water. Advancement in research in this domain will help to protect the environment, human health, and managing this type of pandemic in the future.

SARS-CoV-2 in the environment: Modes of transmission, early detection and potential role of pollutions

The coronavirus disease 2019 (COVID-19) is spreading globally having a profound effect on lives of millions of people, causing worldwide economic disruption. Curbing the spread of COVID-19 and future pandemics may be accomplished through understanding the environmental context of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and adoption of effective detection tools and mitigation policies. This article aims to examine the latest investigations on SARS-CoV-2 plausible environmental transmission modes, employment of wastewater surveillance for early detection of COVID-19, and elucidating the role of solid waste, water, and atmospheric quality on viral infectivity. Transmission of SARS-CoV-2 via faecal-oral or bio-aerosols lacks robust evidence and remains debatable. However, improper disinfection and defected plumbing systems in indoor environments such as hospitals and high-rise towers may facilitate the transport of virus-laden droplets of wastewater causing infection. Clinical and epidemiological studies are needed to present robust evidence that SARS-CoV-2 is transmissible via aerosols, though quantification of virus-laden aerosols at low concentrations presents a challenge. Wastewater surveillance of SARS-CoV-2 can be an effective tool in early detection of outbreak and determination of COVID-19 prevalence within a population, complementing clinical testing and providing decision makers guidance on restricting or relaxing movement. While poor air quality increases susceptibility to diseases, evidence for air pollution impact on COVID-19 infectivity is not available as infections are dynamically changing worldwide. Solid waste generated by households with infected individuals during the lockdown period may facilitate the spread of COVID-19 via fomite transmission route but has received little attention from the scientific community. Water bodies receiving raw sewage may pose risk of infection but this has not been investigated to date. Overall, our understanding of the environmental perspective of SARS-CoV-2 is imperative to detecting outbreak and predicting pandemic severity, allowing us to be equipped with the right tools to curb any future pandemic.

Coronaviruses in the Sea

Interest in coronaviruses because of the 2019 novel coronavirus (SARS-CoV-2) pandemic has generated concern about their occurrence and persistence in aquatic habitats. Coronaviruses are not quantitatively significant constituents of marine virioplankton. Members of the Nidovirales (to which human coronaviruses belong) infect marine mammals, teleosts and possibly invertebrates, and human coronaviruses may persist in marine plankton receiving wastewater effluent. However, virions likely experience significant particle and infectivity decay rates in surface seawater, similar to other enveloped RNA viruses.