Wastewater surveillance of aircraft toilets and major airport hubs: a novel approach for the global surveillance of infectious diseases.

Retelling of the recent COVID-19 pandemic under the One Health perspective, once more stresses out the intimate link between human populations, wildlife and the global anthropic ecosystem. In summary, we could say it also proved to be a chronicle of an expected pandemic. As of today, global efforts to reduce the impacts of emerging diseases are largely focused on post-emergence outbreak control, quarantine, drug & vaccine development. Nevertheless, delays in the detection or effective response to emerging pathogens, combined with increased global urbanization and connectivity, resulted in severe health emergencies. Despite tentative revisions of the International Health Regulations and the efforts made to improve surveillance networks, the implementation of an orchestrated response in case of a rapidly disseminating health emergency, still lags behind. Sensitive and flexible surveillance systems capable of providing an early-warning, definitely require further development at international level. During the COVID-19 pandemic, a growing interest arose in the field of wastewater-based epidemiology, as a valuable strategy for environmental surveillance of pathogens and early-warning system in selected geographical areas. Since it is known that predictive risk for emerging infectious diseases is globally clustered in specific hotspots (i.e. tropical regions experiencing land-use changes and with high wildlife biodiversity, such as Indian subcontinent and other SE Asian countries), it could be envisaged a surveillance network, focusing on high-risk areas. Hereby we discuss the translation of the WBE concept from urban wastewater to aircraft toilets of long-haul flights and main international airport hubs, as a possible strategy of multi-pathogen global surveillance network, based on latest metagenomics approaches. Think global, act local: the time has come for a revolutionary approach to be implemented for the surveillance of infectious diseases, and it urgently needs the joint efforts of both the International community and public health stakeholders.