Respiratory Virus Wastewater Surveillance

Wastewater testing is a useful public health tool that helps monitor the spread of respiratory viruses such as COVID-19, influenza and respiratory syncytial virus (RSV) in the community. While it can indicate the presence of these viruses in the community, it cannot identify whether a specific individual is infected.

Principle of wastewater testing

When people are infected with a respiratory virus, fragments of the virus are shed from the body and enter the sewage system after using the toilet or following washing via sinks and showers. While these fragments are not infectious, they can be detected through laboratory testing of wastewater samples collected from wastewater treatment plants.

Safety

COVID-19, influenza or RSV cannot be transmitted through wastewater.

Purpose of wastewater testing

The wastewater samples are tested for viral fragments of SARS-CoV-2 (the virus that causes COVID-19), influenza and RSV.  Wastewater samples can be used to:

• detect the presence or absence of the virus in a sewer catchment area
• estimate the viral load in community using quantitative analysis
• identify the types of the virus in the community through genomic analysis
• provide an early warning of undiagnosed or under diagnosed viral respiratory illness in the community
• monitor trends over time
• complement other sources of data in the public health management of viral respiratory illnesses.

WA Health has set up an advisory group to guide the wastewater surveillance strategy and to keep the program relevant as new research and techniques emerge.

The Advisory Group consists of representatives from WA Health’s Communicable Disease Control Directorate (CDCD), Environmental Health Directorate (EHD), Boorloo Public Health Unit (BPHU), Western Australia Country Health Service (WACHS),  Water Corporation, and PathWest.