Viral emergence and pandemic preparedness in a One Health framework

The risk of viral pathogen transmission between humans and animals (spillover events) and subsequent spread has been increasing due to human impacts on the planet, which lead to changes in the interactions between humans, animals, ecosystems and their pathogens. Key factors (drivers) that increase the risk of disease emergence include climate change, urbanization, land-use changes and global travel, all of which can alter human-animal-environment interactions and increase the likelihood of zoonotic spillovers and vector-borne diseases. Incorporating data on these drivers (such as ecological shifts and patterns of animal movement) into disease surveillance systems can help identify hot spots for disease emergence, which could in theory enable earlier detection of outbreaks and, in turn, increase the effectiveness of intervention strategies. A One Health approach, emphasizing the interconnectedness of human, animal and environmental health, is advocated for addressing these complex challenges. Although conceptually clear and widely endorsed, implementation of One Health approaches towards primary prevention of spillovers is extremely challenging. Here, we summarize current knowledge on disease emergence and its drivers, and discuss how this knowledge could be used towards primary prevention and for the development of risk-targeted One Health early warning surveillance. We consider integrating innovative tools for diagnostics, surveillance and virus characterization, and propose an outlook towards more integrated prevention, early warning and control of emerging infections at the human-animal interface.