Wastewater-Based Epidemiology for Community Monitoring of SARS-CoV-2: Progress and Challenges

Wastewater-basedepidemiology (WBE) is useful for the surveillanceof severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) incommunities, complementing clinical diagnostic testing of individuals.In this Review, we summarize recent progress and highlight remainingchallenges in monitoring SARS-CoV-2 RNA in wastewater systems forcommunity and environmental surveillance. Very low concentrationsof viral particles and RNA present in the complicated wastewater andsewage sample matrix require efficient sample processing and sensitivedetection. We discuss advantages and limitations of available methodsfor wastewater sample processing, including collection, separation,enrichment, RNA extraction, and purification. Efficient extractionof the viral RNA and removal of interfering sample matrices are criticalto the subsequent reverse transcription-quantitative polymerase chainreaction (RT-qPCR) for sensitive detection of SARS-CoV-2 in wastewater.We emphasize the importance of implementing appropriate controls andmethod validation, which include the use of surrogate viruses forassessing extraction efficiency and normalization against measurablechemical and biological components in wastewater. Critical analysisof the published studies reveals imperative research needs for thedevelopment, validation, and standardization of robust and sensitivemethods for quantitative detection of viral RNA and proteins in wastewaterfor WBE.