Under the microscope: Looking at B.C.’s wastewater surveillance for viruses

Wastewater surveillance for diseases and viral activity gained prominence during the COVID-19 pandemic. Scientists have been monitoring wastewater for pathogens for decades, but the method of estimating virus levels gained public attention at the peak of the pandemic when the spread of the disease was uncertain. The B.C. Centre for Disease Control (BCCDC) has been actively monitoring wastewater from across the province to gauge virus levels, not only for COVID-19 but also for influenza and respiratory syncytial virus (RSV).

Natalie Prystajecky, an environmental microbiologist at the BCCDC, highlighted the importance of wastewater data, stating that it was a significant innovation that emerged during the pandemic. Wastewater surveillance provides valuable insights into the circulation of diseases in communities. Samples of untreated community wastewater can indicate whether cases are increasing or decreasing, providing crucial information for public health officials.

During the Omicron wave of the pandemic in late 2021, B.C.’s testing capacity became overwhelmed, leading to the wastewater monitoring dashboard becoming a reliable source of information about virus levels in the community. The data from the wastewater surveillance program has been made available to the public and has played a vital role in understanding the spread of the virus.

Jesse Shapiro, an associate professor of microbiology and immunology at McGill University, explained the process of wastewater surveillance. Wastewater samples are analyzed in labs where various chemical processes are used to concentrate the samples for sequencing. This sequencing helps identify the genetic code of viruses present in the wastewater, allowing researchers to track virus circulation and dominant variants.

However, funding for wastewater surveillance programs is under threat, with Ontario ending its COVID-19 wastewater surveillance program in July 2024. Prystajecky emphasized the importance of continuing this work and expanding it to study other pathogens like norovirus and salmonella. Shapiro echoed this sentiment, highlighting the need for more open data sharing and public health recommendations based on wastewater surveillance.

As the U.S. government considers cutting funding for vital research institutions involved in wastewater surveillance, there is an opportunity for Canada to step up and fill the void. Investing in scientific research and supporting initiatives like wastewater surveillance is essential for monitoring and detecting emerging diseases. By prioritizing funding for these programs, Canada can play a crucial role in safeguarding public health and responding effectively to future pandemics.