ArticleEnvironmental research2021
Estimating the minimum number of SARS-CoV-2 infected cases needed to detect viral RNA in wastewater: To what extent of the outbreak can surveillance of wastewater tell us?
Article in Environmental research, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 43 papers, 4 of them syntheses that pooled it.
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Who cites it
43 citing papers in PubMed, 4 syntheses or guidelines pooled it, 86 citations in OpenAlex.
- A Systematic Review of Methodological Approaches to SARS-CoV-2 Wastewater Surveillance.Viruses · 2026Pooled it
- Correlation between SARS-CoV-2 RNA concentration in wastewater and COVID-19 cases in community: A systematic review and meta-analysis.Journal of hazardous materials · 2023Pooled it
- Factors influencing SARS-CoV-2 RNA concentrations in wastewater up to the sampling stage: A systematic review.The Science of the total environment · 2022Pooled it
- Wastewater surveillance to infer COVID-19 transmission: A systematic review.The Science of the total environment · 2022Pooled it
- Environmental and microbial factors shaping SARS-CoV-2 RNA decay in wastewater: insights from batch tests and a lab-scale sewer pipeline simulator.Scientific reports · 2026Article
- Monitoring Cross-Border Dissemination of Antimicrobial Resistance (AMR) via Air Travel to Saudi Arabia: Formulation of Monitoring Strategies to Mitigate AMR Concerns.Environmental science & technology · 2026Article
- Wastewater-based surveillance of microbial pathogens in GCC countries (2015-2025): a scoping review and questionnaire survey with stakeholders.Frontiers in public health · 2026Article
- Wastewater-Based Surveillance of SARS-CoV-2 and Modeling of COVID-19 Infection Trends.Tropical medicine and infectious disease · 2025Article
- Post-recovery viral shedding shapes wastewater-based epidemiological inferences.Communications medicine · 2025Article
- The influence of environmental factors on the detection and quantification of SARS-CoV-2 variants in dormitory wastewater at a primarily undergraduate institution.Microbiology spectrum · 2025Article
- Article
- The first detection of SARS-CoV-2 RNA in the wastewater of Bucharest, Romania.Scientific reports · 2024Article
- Monitoring SARS-CoV-2 RNA in wastewater from a shared septic system and sub-sewershed sites to expand COVID-19 disease surveillance.Journal of water and health · 2024Article
- A scoping review of global SARS-CoV-2 wastewater-based epidemiology in light of COVID-19 pandemic.Heliyon · 2024Article
- Long-term monitoring of COVID-19 prevalence in raw and treated wastewater in Salvador, the largest capital of the Brazilian Northeast.Scientific reports · 2023Article
- Structured Ethical Review for Wastewater-Based Testing in Support of Public Health.Environmental science & technology · 2023Article
- Structured Ethical Review for Wastewater-Based Testing.medRxiv : the preprint server for health sciences · 2023Article
- SARS-CoV-2 wastewater-based epidemiology in an enclosed compound: A 2.5-year survey to identify factors contributing to local community dissemination.The Science of the total environment · 2023Article
- Number of COVID-19 cases required in a population to detect SARS-CoV-2 RNA in wastewater in the province of Alberta, Canada: Sensitivity assessment.Journal of environmental sciences (China) · 2023Article
- Persistence of endogenous RNA biomarkers of SARS-CoV-2 and PMMoV in raw wastewater: Impact of temperature and implications for wastewater-based epidemiology.The Science of the total environment · 2023Article
Corrections and comments
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Authors and funding
8 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
There is increasing interest in wastewater-based epidemiology (WBE) of SARS-CoV-2 RNA to serve as an early warning system for a community. Despite successful detection of SARS-CoV-2 RNA in wastewaters sampled from multiple locations, there is still no clear idea on the minimal number of cases in a community that are associated with a positive detection of the virus in wastewater. To address this knowledge gap, we sampled wastewaters from a septic tank (n = 57) and biological activated sludge tank (n = 52) located on-site of a hospital. The hospital is providing treatment for SARS-CoV-2 infected patients, with the number of hospitalized patients per day known. It was observed that depending on which nucleocapsid gene is targeted by means of RT-qPCR, a range of 253-409 positive cases out of 10,000 persons are required prior to detecting RNA SARS-CoV-2 in wastewater. There was a weak correlation between N1 and N2 gene abundances in wastewater with the number of hospitalized cases. This correlation was however not observed for N3 gene. The frequency of detecting N1 and N2 gene in wastewater was also higher than that for N3 gene. Furthermore, nucleocapsid genes of SARS-CoV-2 were detected at lower frequency in the partially treated wastewater than in the septic tank. In particular, N1 gene abundance was associated with water quality parameters such as total organic carbon and pH. In instances of positive detection, the average abundance of N1 and N3 genes in the activated sludge tank were reduced by 50 and 70% of the levels detected in septic tank, suggesting degradation of the SARS-CoV-2 gene fragments already occurring in the early stages of the wastewater treatment process.
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