Abstract Title
Wastewater-based Surveillance of Norovirus and Sapovirus from 2020 - 2024 in Alberta, Canada
Presenter
Judy Qiu, Alberta Public Health Laboratory/University of Alberta
Co-Author(s)
Judy Y. Qiu1,2, Bonita E. Lee3, Rhonda J Rosychuk3, Sudha Bhavanam1, Graham Tipples1,2, Angela Crowe4, Casey R.J. Hubert5, Michael D Parkins6, Xiaoli Pang1
1Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Canada
2 Public Health Laboratory, Alberta Precision Laboratory, Edmonton, Canada
3Department of Pediatrics, University of Alberta, Edmonton, Canada
4Alberta Health, Government of Alberta, Edmonton, Canada
5Department of Biological Sciences, University of Calgary, Calgary, Canada
6Department of Microbiology, University of Calgary, Calgary, Canada
Abstract Category
Food & Environmental Virology-II (Wastewater & others)
Abstract
Human norovirus (NoV) and sapovirus (SaV) are major causes of acute gastroenteritis worldwide. Both viruses are detected in large quantities in raw sewage. The aim of this study is to assess the prevalence of NoV and SaV in wastewater (WW) and their correlation with clinical data.
Viruses were concentrated from raw WW samples collected from 8 WW treatment plants across Alberta during July 2020 - June 2024. Two-step RT-qPCR was used to detect NoV and SaV. Clinical stool samples submitted to Public Health Laboratory were tested for gastroenteritis virus panel (GVP) including NoV and SaV.
The total samples tested and positive for NoV and SaV in WW and clinical samples each year are shown in Table 1. Of the 4579 WW samples tested, 2,809 (61.3%), 3,474 (75.9%), and 2,784 (60.8%) samples were positive for NoV GI, NoV GII and SaV, respectively. During the same period, 15,415 stool specimens were submitted from the sewershed regions for GVP testing, and 159 (1.0%) samples positive for NoV GI, 1,290 (8.4%) for NoV GII, and 365 (2.4%) for SaV. The Pearson correlation coefficient showed moderate association for NoV (0.51) and SaV (0.53) between WW and clinical samples, suggesting that wastewater surveillance can potentially be used for monitoring the disease burden of NoV and SaV in the communities. Overall, NoV had higher prevalence than SaV in both clinical and WW samples. The detection of both viruses significantly decreased during COVID-19 pandemic, indicating that public health interventions for COVID-19 also reduced the transmission of gastroenteritis viruses.
Table 1. Norovirus and sapovirus detection in wastewater and clinical samples from 2020-2024.
wastewater, positive no. (%)clinical samples, positive no. (%)
Testing periodTotal no. of sample testedNoV GINoV GIISaVTotal no. of sample testedNoV GINoV GIISaV
July 2020 - June 20211490404 (27.1)754 (50.6)357 (24.0)26791 (0.0)42 (1.6)3 (0.10)
July 2021 - June 20221131682 (60.3)939 (83.0)722 (63.8)327020 (0.6)346 (10.6)52 (1. 6)
July 2022 - June 202312061056 (87.6)1120 (92.9)1070 (88.7)381159 (1.5)364 (9.6)149 (3.9)
July 2023 - June 2024752667 (88.7)661 (87.9)635 (84.4)565579 (1.4)538 (9.5)161 (2.8)
Viruses were concentrated from raw WW samples collected from 8 WW treatment plants across Alberta during July 2020 - June 2024. Two-step RT-qPCR was used to detect NoV and SaV. Clinical stool samples submitted to Public Health Laboratory were tested for gastroenteritis virus panel (GVP) including NoV and SaV.
The total samples tested and positive for NoV and SaV in WW and clinical samples each year are shown in Table 1. Of the 4579 WW samples tested, 2,809 (61.3%), 3,474 (75.9%), and 2,784 (60.8%) samples were positive for NoV GI, NoV GII and SaV, respectively. During the same period, 15,415 stool specimens were submitted from the sewershed regions for GVP testing, and 159 (1.0%) samples positive for NoV GI, 1,290 (8.4%) for NoV GII, and 365 (2.4%) for SaV. The Pearson correlation coefficient showed moderate association for NoV (0.51) and SaV (0.53) between WW and clinical samples, suggesting that wastewater surveillance can potentially be used for monitoring the disease burden of NoV and SaV in the communities. Overall, NoV had higher prevalence than SaV in both clinical and WW samples. The detection of both viruses significantly decreased during COVID-19 pandemic, indicating that public health interventions for COVID-19 also reduced the transmission of gastroenteritis viruses.
Table 1. Norovirus and sapovirus detection in wastewater and clinical samples from 2020-2024.
wastewater, positive no. (%)clinical samples, positive no. (%)
Testing periodTotal no. of sample testedNoV GINoV GIISaVTotal no. of sample testedNoV GINoV GIISaV
July 2020 - June 20211490404 (27.1)754 (50.6)357 (24.0)26791 (0.0)42 (1.6)3 (0.10)
July 2021 - June 20221131682 (60.3)939 (83.0)722 (63.8)327020 (0.6)346 (10.6)52 (1. 6)
July 2022 - June 202312061056 (87.6)1120 (92.9)1070 (88.7)381159 (1.5)364 (9.6)149 (3.9)
July 2023 - June 2024752667 (88.7)661 (87.9)635 (84.4)565579 (1.4)538 (9.5)161 (2.8)