Occurrence and Decay of SARS-CoV-2 in Community Sewage Drainage Systems

• Published in: Engineering (Beijing, China) Vol. 26; pp. 214 - 219
• Main Authors: Dong, Qian, Cai, Jun-Xiong, Liu, Yan-Chen, Ling, Hai-Bo, Wang, Qi, Xiang, Luo-Jing, Yang, Shao-Lin, Lu, Zheng-Sheng, Liu, Yi, Huang, Xia, Qu, Jiu-Hui
• Format: Journal Article
• Language: English
• Published: China Elsevier Ltd 01.07.2023; THE AUTHORS. Published by Elsevier LTD on behalf of Chinese Academy of Engineering and Higher Education Press Limited Company; Elsevier
• Subjects: Community; Drainage system; SARS-CoV-2; Sewage; Transmission risk; SARS-CoV-2; Drainage system; Sewage; Transmission risk; Community
• ISSN: 2095-8099; 2096-0026
• DOI: 10.1016/j.eng.2022.03.012

[Display omitted] •The study provided most early experience of the sewage surveillance for SARS-CoV-2 in the field.•The risk of emission of SARS-CoV-2 to environment through vent stacks is small.•It takes less than 23 days for SARS-CoV-2 RNA to turn negative in the septic tanks.•Sewage surveillance could be used to monitor the possible presence of asymptomatic infection.•The risk of aerosol transmission within community sewage drainage system is small. The rapid spread of the coronavirus disease (COVID-19) pandemic in over 200 countries poses a substantial threat to human health. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, can be discharged with feces into the drainage system. However, a comprehensive understanding of the occurrence, presence, and potential transmission of SARS-CoV-2 in sewers, especially in community sewers, is still lacking. This study investigated the virus occurrence by viral nucleic acid testing in vent stacks, septic tanks, and the main sewer outlets of community where confirmed patients had lived during the early days of the epidemic in Wuhan, China. The results indicated that the risk of long-term emission of SARS-CoV-2 to the environment via vent stacks of buildings was low after confirmed patients were hospitalized. SARS-CoV-2 were mainly detected in the liquid phase, as opposed to being detected in aerosols, and its RNA in the sewage of septic tanks could be detected for only four days after confirmed patients were hospitalized. The surveillance of SARS-CoV-2 in sewage could be a sensitive indicator for the possible presence of asymptomatic patients in the community, though the viral concentration could be diluted more than ten times, depending on the sampling site, as indicated by the Escherichia coli test. The comprehensive investigation of the community sewage drainage system is helpful to understand the occurrence characteristics of SARS-CoV-2 in sewage after excretion with feces and the feasibility of sewage surveillance for COVID-19 pandemic monitoring.