Wastewater-Based Surveillance Is an Effective Tool for Trending COVID-19 Prevalence in Communities: A Study of 10 Major Communities for 17 Months in Alberta

Abstract

The correlations between SARS-CoV-2 RNA levels in wastewater from 12 wastewater treatment plants and new COVID-19 cases in the corresponding sewersheds of 10 communities were studied over 17 months. The analysis from the longest continuous surveillance reported to date revealed that SARS-CoV-2 RNA levels correlated well with temporal changes of COVID-19 cases in each community. The strongest correlation was found during the third wave ( r = 0.97) based on the population-weighted SARS-CoV-2 RNA levels in wastewater. Different correlations were observed ( r from 0.51 to 0.86) in various sizes of communities. The population in the sewershed had no observed effects on the strength of the correlation. Fluctuation of SARS-CoV-2 RNA levels in wastewater mirrored increases and decreases of COVID-19 cases in the corresponding community. Since the viral shedding to sewers from all infected individuals is included, wastewater-based surveillance provides an unbiased and no-discriminate estimation of the prevalence of COVID-19 compared with clinical testing that was subject to testing–seeking behaviors and policy changes. Wastewater-based surveillance on SARS-CoV-2 represents a temporal trend of COVID-19 disease burden and is an effective and supplementary monitoring when the number of COVID-19 cases reaches detectable thresholds of SARS-CoV-2 RNA in wastewater of treatment facilities serving various sizes of populations.

Surveillance for SARS‐CoV‐2 and its variants in wastewater of tertiary care hospitals correlates with increasing case burden and outbreaks

“…This strategy enables inclusive, objective and unbiased assessment of community COVID‐19 case burden 30 . WBS is a leading indicator of cases, 10,31 hospitalizations 32 and intensive care unit (ICU) admissions 33 . What was once a scientific curiosity is now routinely used globally to monitor COVID‐19 activity and to direct public health policy.…”

Longitudinal and Quantitative Fecal Shedding Dynamics of SARS-CoV-2, Pepper Mild Mottle Virus and CrAssphage

“…[1][2][3] This has led to the widespread adoption of Wastewater-Based Epidemiology (WBE) for tracking community levels of COVID-19. Measurable concentrations of SARS-CoV-2 RNA in wastewater correlate with measures of COVID-19 incidence, [4][5][6][7][8] hospitalizations, 6,9,10 and deaths. 8,11 Although these correlations provide proxies for the relative levels of transmission in a sewershed over time, a mechanistic link between fecal shedding of SARS-CoV-2 RNA with wastewater monitoring would substantially strengthen the utility of WBE methods.…”

Temporal Variation of SARS-CoV-2 Levels in Wastewater from a Meat Processing Plant

“…In a 3-month study of wastewater-based city zonation, the variation of SARS-CoV-2 RNA in the wastewater was shown to lead the change in the confirmed cases by 1-2 weeks, giving the public up to 2 weeks to prepare and manage for the pandemic situation in advance [ 22 ]. Pang et al [ 9 ] showed that different correlations between the wastewater virus levels were observed depending on the sizes of communities, and concluded that the information obtained with WBS was unbiased compared to clinical testing which is highly dependent on the local policies. Another study in Brazil found a lead of 5 days in the detection of SARS-CoV-2 in wastewater compared to the reported positive cases [ 23 ].…”

“…Most WBS studies for COVID-19 focused on analyzing and monitoring wastewater samples taken from wastewater treatment plants (WWTPs) or hospitals [ 1 , 2 , 3 , 4 ]. Several studies showed a correlation between SARS-CoV-2 levels in wastewater and positive COVID-19 cases reported from clinic testing or public records, suggesting that wastewater-based monitoring can provide information for large-scale dynamic of the pandemic [ 5 , 6 , 7 , 8 , 9 ]. Although it is important to investigate the COVID-19 prevalence and dynamic in communities and cities scales, with the negative economic impact of the COVID-19 around the world, the interests of business owners lay in the presence of the viruses and infected individuals in the local facility, which is crucial for updating the control procedures in a timely manner to respond to the decreasing or rising risks and ensuring the safety of the workers during the business recovery stage [ 10 , 11 , 12 ].…”