Journal of Environmental Sciences, Volume 107
- Anthology ID:
- G21-41
- Month:
- Year:
- 2021
- Address:
- Venue:
- GWF
- SIG:
- Publisher:
- Elsevier BV
- URL:
- https://gwf-uwaterloo.github.io/gwf-publications/G21-41
- DOI:
Comparison of approaches to quantify SARS-CoV-2 in wastewater using RT-qPCR: Results and implications from a collaborative inter-laboratory study in Canada
Alex H. S. Chik
|
Melissa B. Glier
|
Mark R. Servos
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Chand S. Mangat
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Xiaoli Pang
|
Yuanyuan Qiu
|
Patrick M. D’Aoust
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Jean-Baptiste Burnet
|
Robert Delatolla
|
Sarah Dorner
|
Qiudi Geng
|
John P. Giesy
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R. Michael L. McKay
|
Michael R. Mulvey
|
Natalie Prystajecky
|
Nivetha Srikanthan
|
Yuwei Xie
|
Bernadette Conant
|
Steve E. Hrudey
Detection of SARS-CoV-2 RNA in wastewater is a promising tool for informing public health decisions during the COVID-19 pandemic. However, approaches for its analysis by use of reverse transcription quantitative polymerase chain reaction (RT-qPCR) are still far from standardized globally. To characterize inter- and intra-laboratory variability among results when using various methods deployed across Canada, aliquots from a real wastewater sample were spiked with surrogates of SARS-CoV-2 (gamma-radiation inactivated SARS-CoV-2 and human coronavirus strain 229E [HCoV-229E]) at low and high levels then provided "blind" to eight laboratories. Concentration estimates reported by individual laboratories were consistently within a 1.0-log10 range for aliquots of the same spiked condition. All laboratories distinguished between low- and high-spikes for both surrogates. As expected, greater variability was observed in the results amongst laboratories than within individual laboratories, but SARS-CoV-2 RNA concentration estimates for each spiked condition remained mostly within 1.0-log10 ranges. The no-spike wastewater aliquots provided yielded non-detects or trace levels (<20 gene copies/mL) of SARS-CoV-2 RNA. Detections appear linked to methods that included or focused on the solids fraction of the wastewater matrix and might represent in-situ SARS-CoV-2 to the wastewater sample. HCoV-229E RNA was not detected in the no-spike aliquots. Overall, all methods yielded comparable results at the conditions tested. Partitioning behavior of SARS-CoV-2 and spiked surrogates in wastewater should be considered to evaluate method effectiveness. A consistent method and laboratory to explore wastewater SARS-CoV-2 temporal trends for a given system, with appropriate quality control protocols and documented in adequate detail should succeed.