Wastewater (WW) surveillance allows monitoring of endemic respiratory viral infections, according to a study presented at the annual meeting of the Infectious Diseases Society of America (IDWeek), held from Oct. 11 to 15 in Boston.
Kristine Du, from the Cumming School of Medicine at the University of Calgary in Alberta, Canada, and colleagues examined the occurrence of influenza A (IAV), influenza B (IBV), and respiratory syncytial virus (RSV) RNA in WW treatment plants (WWTPs) in Alberta’s largest city and the correlation with clinical disease. Twenty-four-hour composite WW samples were collected weekly from three WWTPs in Calgary between March 2022 and April 2023. WW was concentrated and RNA was extracted. Viral RNA was quantified using a commercial TaqMan assay. A composite city-wide metric for each target was created using flow rates at each WWTP.
The researchers observed peaks in IAV, IBV, and RSV in Calgary’s WW for November to December 2022, February to April 2023, and November 2022 to February 2023, respectively. There was a positive correlation seen for the composite IAV signal with weekly confirmed clinical cases within the Calgary Zone, which was seen regardless of influenza typed as H3N2 or H1N1 or untyped. Across the entire province, specimen test positivity rates correlated with Calgary’s WW measured IAV. Across the entire province, the IBV WW signal correlated with clinical cases and test positivity rates. Across Alberta, Calgary’s RSV WW correlated with clinical cases and test positivity rates.
“Knowing what viruses are coming down the pike can help prepare individuals and communities appropriately,” Du said in a statement.
