according to new research reported at an annual scientific meeting on infectious diseases.
The analysis of wastewater in Calgary (Alta.) found a “positive correlation” between positivity rates for these three viruses in wastewater and weekly laboratory-confirmed clinical cases and test positivity rates, study investigator Kristine Du, with Cumming School of Medicine, University of Calgary, told this news organization.
Wastewater monitoring of viral activity has become an established tool for COVID-19 pandemic monitoring, providing a leading indicator to cases and hospitalizations. However, less is known about its potential for monitoring endemic respiratory viruses.
The new study shows that wastewater-based surveillance is a “robust and adaptable” tool for community-level surveillance of seasonal respiratory viruses – “one that can complement health care clinical testing because it’s independent from testing biases, and we can actually correlate our cases very well with it,” Ms. Du said during a preconference media briefing.
Tracking community trends
For the study, Ms. Du and colleagues assessed the occurrence of influenza A, influenza B, and RSV RNA in all three wastewater treatment plants in Calgary between March 2022 and April 2023 and its correlation with clinical disease.
They found that viral signals in Calgary’s wastewater for influenza A and B and RSV correlated significantly with weekly confirmed clinical cases in Calgary residents.
Influenza A peaked in Calgary’s wastewater between November and December 2022; influenza B peaked between February and April 2023; and RSV between November 2022 and February 2023.
“Wastewater gives us unbiased, objective, and comprehensive data. It can be used in addition to other testing for assessing the community burden that disease may have, and it is complementary to clinical testing,” Ms. Du said.
Their team, Ms. Du said, is continuing to proactively monitor wastewater for influenza and RSV, as well as other agents of “pandemic potential to make sure we know what could affect humans – and make sure everyone is aware of that.”
Commenting on the research, briefing moderator Belinda Ostrowsky, MD, MPH, Albert Einstein College of Medicine, New York, said, “Wastewater surveillance illustrates how understanding community levels of viral trends can identify hotspots, inform local public health decision-making, and prepare clinicians and hospitals for potential outreach. This topic is particularly timely as we head into the flu and RSV season.”
The study had no commercial funding. Ms. Du and Dr. Ostrowsky report no relevant financial relationships.
A version of this article first appeared on Medscape.com.