TY - JOUR
T1 - SARS-CoV-2 RNA surveillance in large to small centralized wastewater treatment plants preceding the third COVID-19 resurgence in Bangkok, Thailand
AU - Sangsanont, Jatuwat
AU - Rattanakul, Surapong
AU - Kongprajug, Akechai
AU - Chyerochana, Natcha
AU - Sresung, Montakarn
AU - Sriporatana, Nonnarit
AU - Wanlapakorn, Nasamon
AU - Poovorawan, Yong
AU - Mongkolsuk, Skorn
AU - Sirikanchana, Kwanrawee
N1 - Funding Information:
This work was financially supported by the TSRI Fund ( CU_FRB640001_01_21_6 ), Research Strengthening Project of Faculty of Engineering ( King Mongkut's University of Technology Thonburi ) and the Chulabhorn Research Institute (grant no. 312/3057 ). Ms. Thitima Srathongneam is thankfully acknowledged for assistance with map preparation. We acknowledge the Department of Drainage and Sewerage, Bangkok Metropolitan Administration (BMA), and the Division of Communicable Disease Control, Department of Health, BMA, for providing data on wastewater flow rates and daily new cases.
Funding Information:
This work was financially supported by the TSRI Fund (CU_FRB640001_01_21_6), Research Strengthening Project of Faculty of Engineering (King Mongkut's University of Technology Thonburi) and the Chulabhorn Research Institute (grant no. 312/3057). Ms. Thitima Srathongneam is thankfully acknowledged for assistance with map preparation. We acknowledge the Department of Drainage and Sewerage, Bangkok Metropolitan Administration (BMA), and the Division of Communicable Disease Control, Department of Health, BMA, for providing data on wastewater flow rates and daily new cases.
Publisher Copyright:
© 2021 The Authors
PY - 2022/2/25
Y1 - 2022/2/25
N2 - Wastewater surveillance for SARS-CoV-2 RNA has been a successful indicator of COVID-19 outbreaks in populations prior to clinical testing. However, this has been mostly conducted in high-income countries, which means there is a dearth of performance investigations in low- and middle-income countries with different socio-economic settings. This study evaluated the applicability of SARS-CoV-2 RNA monitoring in wastewater (n = 132) to inform COVID-19 infection in the city of Bangkok, Thailand using CDC N1 and N2 RT-qPCR assays. Wastewater influents (n = 112) and effluents (n = 20) were collected from 19 centralized wastewater treatment plants (WWTPs) comprising four large, four medium, and 11 small WWTPs during seven sampling events from January to April 2021 prior to the third COVID-19 resurgence that was officially declared in April 2021. The CDC N1 assay showed higher detection rates and mostly lower Ct values than the CDC N2. SARS-CoV-2 RNA was first detected at the first event when new reported cases were low. Increased positive detection rates preceded an increase in the number of newly reported cases and increased over time with the reported infection incidence. Wastewater surveillance (both positive rates and viral loads) showed strongest correlation with daily new COVID-19 cases at 22–24 days lag (Spearman's Rho = 0.85–1.00). Large WWTPs (serving 432,000–580,000 of the population) exhibited similar trends of viral loads and new cases to those from all 19 WWTPs, emphasizing that routine monitoring of the four large WWTPs could provide sufficient information for the city-scale dynamics. Higher sampling frequency at fewer sites, i.e., at the four representative WWTPs, is therefore suggested especially during the subsiding period of the outbreak to indicate the prevalence of COVID-19 infection, acting as an early warning of COVID-19 resurgence.
AB - Wastewater surveillance for SARS-CoV-2 RNA has been a successful indicator of COVID-19 outbreaks in populations prior to clinical testing. However, this has been mostly conducted in high-income countries, which means there is a dearth of performance investigations in low- and middle-income countries with different socio-economic settings. This study evaluated the applicability of SARS-CoV-2 RNA monitoring in wastewater (n = 132) to inform COVID-19 infection in the city of Bangkok, Thailand using CDC N1 and N2 RT-qPCR assays. Wastewater influents (n = 112) and effluents (n = 20) were collected from 19 centralized wastewater treatment plants (WWTPs) comprising four large, four medium, and 11 small WWTPs during seven sampling events from January to April 2021 prior to the third COVID-19 resurgence that was officially declared in April 2021. The CDC N1 assay showed higher detection rates and mostly lower Ct values than the CDC N2. SARS-CoV-2 RNA was first detected at the first event when new reported cases were low. Increased positive detection rates preceded an increase in the number of newly reported cases and increased over time with the reported infection incidence. Wastewater surveillance (both positive rates and viral loads) showed strongest correlation with daily new COVID-19 cases at 22–24 days lag (Spearman's Rho = 0.85–1.00). Large WWTPs (serving 432,000–580,000 of the population) exhibited similar trends of viral loads and new cases to those from all 19 WWTPs, emphasizing that routine monitoring of the four large WWTPs could provide sufficient information for the city-scale dynamics. Higher sampling frequency at fewer sites, i.e., at the four representative WWTPs, is therefore suggested especially during the subsiding period of the outbreak to indicate the prevalence of COVID-19 infection, acting as an early warning of COVID-19 resurgence.
KW - COVID-19 pandemic
KW - Environmental surveillance
KW - Human sewage
KW - Sewage treatment plants
KW - Wastewater-based epidemiology
UR - http://www.scopus.com/inward/record.url?scp=85119156300&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2021.151169
DO - 10.1016/j.scitotenv.2021.151169
M3 - Article
C2 - 34699826
AN - SCOPUS:85119156300
SN - 0048-9697
VL - 809
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 151169
ER -