Early in the COVID-19 pandemic it was established that fragments of the COVID-19 (SARS-CoV-2) virus could be detected in untreated sewage, providing an opportunity to track infections in the community alongside existing testing efforts (Mallapaty 2020).
The wastewater monitoring project rapidly pivoted existing technology to verify the sensitivity and specificity of the approach of detecting SARS-CoV-2 fragments in wastewater. Additional funding was subsequently provided by NSW Health to operationalise the method and establish a statewide COVID-19 wastewater surveillance program.
A microbiological sampling procedure and checklist for COVID-19 sewage surveillance were produced, and technical knowledge, including methods and protocols, was shared internationally (The Water Research Foundation 2020). Methods validated through the wastewater testing pilot were incorporated into the NSW Sewage Surveillance Program, which provided critical intelligence via reporting of test results to NSW Health, other state and territory jurisdictions and the Australian Government, as well as to the public via the NSW Health website (HPNSW 2022).
Findings from the Surveillance Program have enabled NSW Health to target messaging and testing to high-risk areas, tracking possible COVID-19 clusters and outbreaks and managing movement restrictions following a known outbreak. For example, in the Northern Beaches region (an outer-suburban area of metropolitan Sydney), COVID-19 viral fragments were detected in sewage on 16 December 2020, the same day as two confirmed clinical cases of COVID-19 in the area. The specificity of the data contributed to the Northern Beaches being segmented into upper and lower regions, with stricter restrictions in the upper region, including limited movement out of the area. Continued monitoring of COVID-19 detections in sewage also informed subsequent easing of restrictions in the lower region.
References:
Richard Broome1, Andrew Milat2, Danielle Campbell2
