Surveillance of SARS-CoV-2 in Urban Wastewater in Italy

The presence of SARS-CoV-2 RNA in wastewaters was demonstrated early into the COVID-19 pandemic. Data on the presence of SARS-CoV-2 in urban wastewater can be exploited for different aims, including: i) description of outbreaks trends, ii) early warning system for new COVID-19 outbreaks or for the spread of the virus in new territories, iii) study of SARS-Co V-2 genetic diversity and detection of its variants, and iv) estimating the prevalence of COVID-19 infections. Therefore, wastewater surveillance (known as Wastewater Based Epidemiology, WBE) can be a powerful tool to support the decision-making process on public health measures. Italy was among the first EU countries investigating the occurrence and concentration of SARS-Co V-2 RNA in urban wastewaters, virus detection being accomplished at an early phase of the epidemic, between February and May 2020 in north and central Italy. The present study reports on the methodological issues, related to sample data collection and management, encountered in establishing the systematic, wastewater-based SARS-CoV-2 surveillance, and describes the results of the first six months of surveillance.