Wastewater-based surveillance (WBS) has been successfully used for decades for public health purposes in Europe, e.g. to monitor the circulation of poliovirus in the population [1]. Although not a new tool, it was during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic that WBS was incorporated alongside other, more traditional surveillance tools such as community and clinical testing [2-4].

During the SARS-CoV-2 pandemic, the European Commission recommended that all European Union (EU) countries implement SARS-CoV-2 WBS beginning in March 2021 and no later than October 2021 [5]. This initiative was strengthened in 2022 by the World Health Organization interim guidance Environmental surveillance for SARS-COV-2 to complement public health surveillance [6]. Since then, several European countries have developed WBS systems to monitor the occurrence and spread of SARS-CoV-2, as documented by the Digital European Exchange Platform of the EU Sewage Sentinel System for SARS-CoV-2 [7,8]. By 2023, the pressure of the SARS-CoV-2 pandemic on communities and their health systems had notably diminished and individual testing was generally at its lowest level, yet WBS has remained at the frontline of SARS-CoV-2 surveillance.

Disease surveillance is information that can and should be used for action and the knowledge gathered can be translated into intervention through decision-making [9-11]. Asking questions like ‘Is WBS beyond SARS-CoV-2 relevant in Europe?’ and ‘What are the problems to be solved next and through what strategies?’ become key to address preparedness against viral and bacterial pathogens with a pandemic potential. Furthermore, the 2022 revision of the EU’s Urban Wastewater Treatment Directive aimed to ‘require EU countries to monitor pathogens in wastewater’ [12,13]. It is therefore important to review how the WBS experience gained with the SARS-CoV-2 pandemic is being capitalised upon and applied to prevent current and future threats. Through a survey conducted at the end of 2023, we collected and critically described knowledge about the objectives, approaches, representativeness and usefulness of WBS systems of pathogens of human relevance in 10 European countries. Moreover, we discussed the experiences, lessons learned and future opportunities/perspectives from the participating European countries.