Wastewater Surveillance at the Crossroads: Public Good, Private Data, and Ethical Boundaries.

Wastewater-based epidemiology has rapidly evolved and is getting attention during and after the COVID-19 pandemic, becoming a key tool for monitoring infectious diseases and improving preparedness in case of a new pandemic. However, the development of ethical, legal, and regulatory frameworks has not kept pace with their technical implementation. This manuscript highlights crucial challenges associated with wastewater surveillance, such as, data ownership, potential of stigmatization, regulations, and wastewater transportation. With particular attention to cases where assumptions of anonymity may no longer hold, and risks of stigmatization increase, which can easily happen in small or targeted populations (e.g., aircraft, prisons). Misinterpretation of open-access data is also discussed as it can be amplified through social and traditional media, potentially undermining public health communication. In addition, regulatory gaps in the classification and transportation of wastewater samples are highlighted here, especially for low-volume wastewater samples that fall outside existing regulations. Wastewater data should be protected as a public resource and used primarily for public health purposes. To achieve that, clearer mandates and guidelines for research should be developed in a multidisciplinary environment to strengthen ethical and equitable public health decisions.