Wastewater, waste, and water-based epidemiology (WWW-BE): A novel hypothesis and decision-support tool to unravel COVID-19 in low-income settings?

Abstract

Traditional wastewater-based epidemiology (W-BE) relying on SARS-CoV-2 RNA detection in wastewater is attractive for understanding COVID-19. Yet traditional W-BE based on centralized wastewaters excludes putative SARS-CoV-2 reservoirs such as: (i) wastewaters from shared on-site sanitation facilities, (ii) solid waste including faecal sludge from non-flushing on-site sanitation systems and COVID-19 personal protective equipment (PPE), (iii) raw/untreated water, and (iv) drinking water supply systems in low-income countries (LICs). A novel hypothesis and decision-support tool based on Wastewater (on-site sanitation, municipal sewer systems), solid Waste, and raw/untreated and drinking Water-based epidemiology (WWW-BE) is proposed for understanding COVID-19 in LICs. The WWW-BE conceptual framework, including components and principles is presented. Evidence on the presence of SARS-CoV-2 and its proxies in wastewaters, solid materials/waste (papers, metals, fabric, plastics), and raw/untreated surface water, groundwater and drinking water is discussed. Taken together, wastewaters from municipal sewer and on-site sanitation systems, solid waste such as faecal sludge and COVID-19 PPE, raw/untreated surface water and groundwater, and drinking water systems in LICs act as reservoirs that receive and harbour SARS-CoV-2, and then transmit it to humans. Hence, WWW-BE could serve a dual function in estimating the prevalence and potential transmission of COVID-19. Several applications of WWW-BE as a hypothesis and decision support tool in LICs are discussed. WWW-BE aggregates data from various infected persons in a spatial unit, hence, putatively requires less resources (analytical kits, personnel) than individual diagnostic testing, making it an ideal decision-support tool for LICs. The novelty, and a critique of WWW-BE versus traditional W-BE are presented. Potential challenges of WWW-BE include: (i) biohazards and biosafety risks, (ii) lack of expertise, analytical equipment, and accredited laboratories, and (iii) high uncertainties in estimates of COVID-19 cases. Future perspectives and research directions including key knowledge gaps and the application of novel and emerging technologies in WWW-BE are discussed.

First case of SARS-CoV-2 RNA detection in municipal solid waste leachate from Brazil

“… Gwenzi (2021) also proposed an alternative methodology for tracking SARS-CoV-2, which involves the detection of viral RNA titers not only in wastewater samples but also in solid waste (papers, metals, fabric, plastics), and raw/untreated and drinking water. The authors draw the attention of the research community, governments, local and international health authorities, and professionals in wastewater-based epidemiology to the development of new low-cost tools for COVID-19 surveillance, especially for low-income regions.…”

“…Worried about the possibility of surface transmission through municipal solid waste (MSW) ( Ong et al, 2020 ; Ren et al, 2020 ; Gwenzi, 2021 ), municipalities, agencies, and scientists proposed educational programs about the proper separation of Personal Protection Equipment (PPE) used by common citizens, sorted by what can be recycled or not ( Vaverková et al, 2021 ). Along with the massive participation of households in this process, a 72-h quarantine was also proposed in time to time to decrease the waste amount generated to allow it to be sorted and finally sent to the recycling industries ( LfU, 2020 ; ACRPlus, 2020 ).…”

“…Along with the massive participation of households in this process, a 72-h quarantine was also proposed in time to time to decrease the waste amount generated to allow it to be sorted and finally sent to the recycling industries ( LfU, 2020 ; ACRPlus, 2020 ). Many municipalities had suspended the selective collection or closed the volunteer points to deliver recyclables and, therefore, many sorting plants stopped their operation, decreasing the useful life of sanitary landfills and carrying social, environmental and economical unbalance to the recycling industries and pickers employment ( Gwenzi, 2021 ; Vaverková et al, 2021 ).…”

Dependency of sanitation infrastructure on the discharge of faecal coliform and SARS-CoV-2 viral RNA in wastewater from COVID and non-COVID hospitals in Dhaka, Bangladesh

“…SARS-CoV-2 RNA in sewage samples was also detected in the vicinity of the COVID-19 isolation centre in south-eastern Bangladesh ( Ahmed et al, 2021 ). Quantifying the concentration of viruses in wastewater could serve as a proxy for monitoring disease transmission among the population, which is an approach termed as “wastewater-based epidemiology” (WBE) ( Ahmed et al, 2020 ; Aguiar-Oliveira et al, 2020 ; Bhattacharya et al, 2021 ; Buonerba et al, 2021 ; Gwenzi, 2022 ; Huisman et al, 2022 ; Islam et al, 2023b ; Lodder et al, 2013 ; Wu et al, 2020a ; Zhang et al, 2020b ). In fact, SARS-CoV-2 RNA concentration in the wastewater and hospital effluent samples correlated with the number of reported COVID-19 cases in different countries ( Majumder et al, 2021 ).…”

Utilization of SARS-CoV-2 Wastewater Surveillance in Africa—A Rapid Review

“…While epidemiology for SARS-CoV-2 RNA detection in wastewater is attractive for understanding COVID-19 in settings where financial and diagnostic resources for testing are severely limited, there is a lack of research evidence on the utility of such techniques in Africa. The availability of reliable data on COVID-19 burden and transmission is critical for prioritising and deploying scarce resources, including personal protective equipment (PPE) and emergence response systems [ 26 ]. Thus, this study aimed to map research evidence on SARS-CoV-2 wastewater surveillance in Africa to inform future research and synthesize gaps and opportunities.…”