COVID-19 in City of Kingston Wastewater
KFL&A Public Health is pleased to partner with Utilities Kingston and Queen's University to present results for COVID-19 testing in the City of Kingston's wastewater. Identifying COVID-19 in our wastewater may help identify COVID-19 in our community.
How does wastewater testing prevent the spread of COVID-19
People with active COVID-19 infection shed the virus in their stool before they are symptomatic, when they are symptomatic, or if they are asymptomatic. Testing wastewater may identify the presence of the virus in asymptomatic people before traditional testing.
Queen’s University’s Beaty Water Research Centre (BWRC) and Utilities Kingston is participating in the Wastewater Surveillance Initiative sponsored by the Ministry of the Environment, Conservation and Parks (MECP) to implement wastewater surveillance for COVID-19 virus. BWRC are currently testing 2 samples per week from each wastewater treatment plant serving the City of Kingston, including samples that have been archived since last spring. They are currently not testing for COVID-19 variants.
Frequently asked questions
What is wastewater epidemiology? |
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Wastewater epidemiology is a relatively new field of research that studies the chemical and biological contents of human waste for clues about disease status and transmission, drug use, or even the overall health status for a population. It relies on the fact that all people excrete waste and that the majority of our waste is flushed away to wastewater treatment plants or septic systems. By analyzing the wastewater at the facilities, we may be able to detect information about the resident population as a whole—that may otherwise be unknown—to enable earlier or better public health action. |
What can wastewater epidemiology tell us? |
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By analyzing wastewater we can test for the presence of chemicals or biological byproducts that signal whether concentrations of potential infectious diseases, like COVID-19, or other public health concerns such as the use of illicitly-acquired drugs (like fentanyl), are increasing or decreasing. To be clear, the testing cannot identify affected individuals. Instead, it lets public health know that a concerning chemical or biological byproduct is present and to start action, such as informing the public or increasing testing (e.g., testing for COVID-19). |
Why are we measuring COVID-19 in wastewater? |
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In the KFL&A region, we track the number of daily new cases of COVID-19, the number of active cases, and the outbreaks of COVID-19 in workplaces, schools, and specialized care facilities like retirement homes. Part of the challenges of living with COVID-19 in our communities is the fact that people may be infected with the virus (called SARS-CoV-2) but do not experience symptoms, and, unknowingly, may spread the virus more widely. We are unable to precisely estimate the number of people who may have COVID-19, or who do not get tested, either because they do not have symptoms or choose not to. We do know that people with COVID-19 shed the virus in their stool whether they are symptomatic or not, and even before they are symptomatic. For the City of Kingston, the water we flush or send down the drain ends up at our wastewater treatment plants. Measuring COVID-19 in wastewater is one method that helps us estimate if the number of cases for city residents are increasing or decreasing according to trends in virus counts in our wastewater. Knowing this can allow public health to respond accordingly, whether increasing public messaging and protective policies, or by relaxing restrictions when all measures of surveillance indicate that the risk of transmissions is lower. |
What is SARS-CoV-2 RNA? |
| The method to detect the COVID-19 virus (SARS-CoV-2) in wastewater measures genetic material present in the virus (RNA). RNA, or ribonucleic acid, is a class of molecules found in all cells. |
How does this work in Kingston? |
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Supported by Ontario’s Ministry of Environment, MECP), researchers at Queen’s University’s Beaty Water Research Centre (BWRC) have partnered with Utilities Kingston to measure the amount of SARS-CoV-2 RNA in samples from both of Kingston’s wastewater treatment facilities (Cataraqui Bay and Ravensview) Several days a week, a sample is collected from each wastewater treatment facility and transported to the BWRC lab where it is prepared and analyzed for SARS-CoV-2. Those measurements are shared with both the MECP and KFL&A Public Health, who use the results in their assessment of COVID-19 transmission risk for the Kingston community, in addition to COVID testing results detecting the number of new daily cases, active cases, and outbreaks. |
What do Kingston’s results mean? |
| From what we have learned so far, the counts in wastewater were consistently low in February, with small increases found in March. The Queen’s University BWRC team had also collected some samples in 2020, and they archived them in a freezer. They will be analyzing those samples to give us a picture of what was happening in the community last year. Those results will be analyzed in the next few weeks. It is hoped that by comparing the historic levels of the virus in wastewater with current case counts in Kingston, we will be able to uncover patterns to help us use this assessment method as a predictive tool. |
What are “counts per ml”? |
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The “counts per ml” are the number of copies of the target RNA found in a milliliter (ml) of raw sewage from the whole community served by the specific wastewater treatment facility. We are primarily concerned with the trends in the data (for example, are the counts increasing, stable, or decreasing?) to help us interpret what is happening in the community. |
When will my community’s wastewater be tested? |
| We are only testing wastewater samples from participating municipal treatment facilities at this point, and for the KFL&A region that is Utilities Kingston, but we will expand our reach as we are able. |