Wastewater testing and monitoring is an emerging tool and investment for the COVID-19 pandemic and future health threats. Solely relying on PCR testing (nose or throat swabs to detect active infections) has limitations when laboratories and public health departments are overwhelmed. Wastewater testing provides additional testing capacity that: detects infection at all stages including asymptomatic cases; costs less than clinical testing; enables quick identification of outbreaks and waves; and is equitable in its ability to both include everyone and focus on vulnerable populations. CoVaRR-Net has established a Wastewater Surveillance Group because of its important use now and moving forward—wastewater testing is expected to be part of our pandemic preparedness toolkit. It will serve us as we navigate the COVID-19 pandemic and, in the future, it will enable detection of emerging infections, pandemics, endemic diseases, drugs, toxins, and pesticides and will serve as a key public health protection and early warning tool. However, as a relatively new tool, more research is needed to improve testing methods and to evaluate its surveillance role.
Why Test Wastewater?
Wastewater addresses several key surveillance challenges. Many people with SARS-CoV-2, the virus that causes COVID-19, are infectious before they have symptoms. People infected with SARS-CoV-2, including individuals without symptoms, shed the virus in their stool. By measuring viral levels within genetic material in the wastewater, public health officials can assess trends and variations in local SARS-CoV-2 infection without physically testing everyone. In some situations, measured wastewater trends can forecast COVID-19 symptomatic cases and hospitalizations in the population ahead of time. Therefore, monitoring the virus in wastewater constitutes an early monitoring system for virus spread and detection of new variants. As outlined by the National Collaborating Centre for Infectious Diseases, wastewater surveillance also anonymously covers a majority of the population. Because of its robust capabilities, wastewater monitoring is becoming a key part of our pandemic preparedness toolkit.
What does CoVaRR-Net’s Wastewater Surveillance Group do?
CoVaRR-Net’s Wastewater Surveillance Group (WWSG) brings together Canadian wastewater and environment investigators from universities across Canada, the Public Health Agency of Canada/National Microbiology Laboratory, and provincial wastewater surveillance programs. Worldwide, CoVaRR-Net is one of the few networks to bring a broad multidisciplinary approach to environmental surveillance through collaboration across Network Pillars 5, 6, 7, and 8.
The WWSG uses a multidisciplinary, consensus approach to establish best practices for wastewater testing and surveillance. Wastewater Surveillance Group members actively collaborate with wastewater teams across Canada involving 200 researchers and public health staff at over 250 testing sites, including in the Canadian North where wastewater has become a key surveillance tool and a centre of innovation.