Wastewater testing has a history of informing public health action through its use to monitor health threats such as polio, antimicrobial resistance, and illicit drug use in populations. It can be used to detect components of SARS-CoV-2. SARS-CoV-2 has characteristics which pose a challenge for public health surveillance approaches. These include a high rate of transmission by symptomatic, asymptomatic, and pre-symptomatic individuals that leads to missed case detection and an interval between viral transmission to clinical testing that leads to delays in case detection.
These characteristics of SARS-CoV-2 infection, along with the observation that SARSCoV-2 is excreted in stools during all phases of infection, has led to the uptake of wastewater testing to complement SARS-CoV-2 surveillance based on clinical tests and case identification.