tetano
Editor, Senior Moderator
Sci Total Environ
. 2022 Nov 7;159996.
doi: 10.1016/j.scitotenv.2022.159996. Online ahead of print.
Detection of SARS-CoV-2 RNA in wastewater and comparison to COVID-19 cases in two sewersheds, North Carolina, USA
Alyssa M Grube[SUP] 1 [/SUP], Collin K Coleman[SUP] 1 [/SUP], Connor D LaMontagne[SUP] 1 [/SUP], Megan E Miller[SUP] 1 [/SUP], Nikhil Kothegal[SUP] 1 [/SUP], David A Holcomb[SUP] 2 [/SUP], A Denene Blackwood[SUP] 3 [/SUP], Thomas J Clerkin[SUP] 3 [/SUP], Marc L Serre[SUP] 1 [/SUP], Lawrence S Engel[SUP] 4 [/SUP], Virginia T Guidry[SUP] 5 [/SUP], Rachel T Noble[SUP] 3 [/SUP], Jill R Stewart[SUP] 6 [/SUP]
Affiliations
Abstract
Wastewater surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be useful for monitoring population-wide coronavirus disease 2019 (COVID-19) infections, especially given asymptomatic infections and limitations in diagnostic testing. We aimed to detect SARS-CoV-2 RNA in wastewater and compare viral concentrations to COVID-19 case numbers in the respective counties and sewersheds. Influent 24-hour composite wastewater samples were collected from July to December 2020 from two municipal wastewater treatment plants serving different population sizes in Orange and Chatham Counties in North Carolina. After a concentration step via HA filtration, SARS-CoV-2 RNA was detected and quantified by reverse transcription droplet digital polymerase chain reaction (RT-ddPCR) and quantitative PCR (RT-qPCR), targeting the N1 and N2 nucleocapsid genes. SARS-CoV-2 RNA was detected by RT-ddPCR in 100 % (24/24) and 79 % (19/24) of influent wastewater samples from the larger and smaller plants, respectively. In comparison, viral RNA was detected by RT-qPCR in 41.7 % (10/24) and 8.3 % (2/24) of samples from the larger and smaller plants, respectively. Positivity rates and method agreement further increased for the RT-qPCR assay when samples with positive signals below the limit of detection were counted as positive. The wastewater data from the larger plant generally correlated (⍴ ~0.5, p < 0.05) with, and even anticipated, the trends in reported COVID-19 cases, with a notable spike in measured viral RNA preceding a spike in cases when students returned to a college campus in the Orange County sewershed. Correlations were generally higher when using estimates of sewershed-level case data rather than county-level data. This work supports use of wastewater surveillance for tracking COVID-19 disease trends, especially in identifying spikes in cases. Wastewater-based epidemiology can be a valuable resource for tracking disease trends, allocating resources, and evaluating policy in the fight against current and future pandemics.
Keywords: COVID; Coronavirus; Sewage surveillance; Wastewater-based epidemiology; ddPCR.
. 2022 Nov 7;159996.
doi: 10.1016/j.scitotenv.2022.159996. Online ahead of print.
Detection of SARS-CoV-2 RNA in wastewater and comparison to COVID-19 cases in two sewersheds, North Carolina, USA
Alyssa M Grube[SUP] 1 [/SUP], Collin K Coleman[SUP] 1 [/SUP], Connor D LaMontagne[SUP] 1 [/SUP], Megan E Miller[SUP] 1 [/SUP], Nikhil Kothegal[SUP] 1 [/SUP], David A Holcomb[SUP] 2 [/SUP], A Denene Blackwood[SUP] 3 [/SUP], Thomas J Clerkin[SUP] 3 [/SUP], Marc L Serre[SUP] 1 [/SUP], Lawrence S Engel[SUP] 4 [/SUP], Virginia T Guidry[SUP] 5 [/SUP], Rachel T Noble[SUP] 3 [/SUP], Jill R Stewart[SUP] 6 [/SUP]
Affiliations
- PMID: 36356771
- DOI: 10.1016/j.scitotenv.2022.159996
Abstract
Wastewater surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be useful for monitoring population-wide coronavirus disease 2019 (COVID-19) infections, especially given asymptomatic infections and limitations in diagnostic testing. We aimed to detect SARS-CoV-2 RNA in wastewater and compare viral concentrations to COVID-19 case numbers in the respective counties and sewersheds. Influent 24-hour composite wastewater samples were collected from July to December 2020 from two municipal wastewater treatment plants serving different population sizes in Orange and Chatham Counties in North Carolina. After a concentration step via HA filtration, SARS-CoV-2 RNA was detected and quantified by reverse transcription droplet digital polymerase chain reaction (RT-ddPCR) and quantitative PCR (RT-qPCR), targeting the N1 and N2 nucleocapsid genes. SARS-CoV-2 RNA was detected by RT-ddPCR in 100 % (24/24) and 79 % (19/24) of influent wastewater samples from the larger and smaller plants, respectively. In comparison, viral RNA was detected by RT-qPCR in 41.7 % (10/24) and 8.3 % (2/24) of samples from the larger and smaller plants, respectively. Positivity rates and method agreement further increased for the RT-qPCR assay when samples with positive signals below the limit of detection were counted as positive. The wastewater data from the larger plant generally correlated (⍴ ~0.5, p < 0.05) with, and even anticipated, the trends in reported COVID-19 cases, with a notable spike in measured viral RNA preceding a spike in cases when students returned to a college campus in the Orange County sewershed. Correlations were generally higher when using estimates of sewershed-level case data rather than county-level data. This work supports use of wastewater surveillance for tracking COVID-19 disease trends, especially in identifying spikes in cases. Wastewater-based epidemiology can be a valuable resource for tracking disease trends, allocating resources, and evaluating policy in the fight against current and future pandemics.
Keywords: COVID; Coronavirus; Sewage surveillance; Wastewater-based epidemiology; ddPCR.