Detection and Quantification of Sars-Cov-2 And Influenza Viruses in Wastewater Treatment Plants Located in Ticino Region (Switzerland)

Abstract Background: wastewater-based epidemiology (WBE) is a promising approach that has been used to monitoring the exposure to pathogens and understanding the status of disease outbreaks in defined population groups. Target: viral RNAs of SARS-Cov-2 and influenza A and B were detected and quantified in three wastewater treatment plants (WWTP) selected in different regions of Canton Ticino (Switzerland). Methodology: Two commercial kits were used to concentrate and extract viral RNAs from wastewater samples and quantify it by RT-qPCR targeting genes specific for SARS-Cov-2, influenza A and influenza B. Results: we have monitored the presence of SARS-CoV-2 during two big waves of pandemic, from March 2021 until June 2023, when number of confirmed cases and tests decreased. The presence of influenza A and B viruses was investigated from October 2022 to June 2023. Conclusion: we confirmed the presence of SARS-CoV-2 and influenza A and B in all the WWTP monitored; RNA concentration in wastewater could be correlated with clinical cases confirming that WBE is a powerful tool to monitor diseases dissemination supporting the management of an epidemic.