Leveraging high-resolution connectivity data for pandemic preparedness: from potential emergence areas to nodes of global human mobility

Projecting scenarios for the spread of emerging infectious diseases (EID) well before a possible next “Disease X” pandemic has become a challenge of utmost importance and urgency. To quantify the actual risk of pathogen spillover, a One Health vision requires us to map both the distribution of key reservoir species for detecting zoonotic pathogen emergence in risky source regions (hazard) and the local human presence (exposure) in an integrative way. At the same time, it is necessary to understand the interplay between local-scale human movement flows and long-range international traffic in shaping the spatiotemporal pattern of EID transmission. Leveraging the data made available in the context of the NetMob 2024 Data Challenge, we developed a prototypical framework of analysis to estimate a geographically informed risk of potential pathogen spillover, coupling in a multicriterial way the hazard associated with pathogen emergence and the exposure proxied by human density. Starting from the estimated disease emergence risk, the method also permits the propagation of the estimated disease emergence risk from local areas of potential pathogen spillover to centers of international spread, such as airports, through the superimposition of a human mobility network layer. We considered Indonesia as a focus case study, demonstrating our method for zoonotic pathogens circulating in Pteropodidae bat populations, which are known reservoirs of several priority viruses in terms of pandemic potential. Contrary to the basic hypothesis that air traffic could be used as the only dominant proxy of potential disease propagation, we find that the risk of spread associated with travelers from different airports is variable, thus highlighting that also relatively marginal, yet crucially located airports in source regions could be pivotal for international disease spread and large-scale transmission control strategies. The international risk of potential spread across the flight destinations is finally illustrated. Driven by hot-of-the-press news of a Nipah virus outbreak in the Kerala state of India in September 2024, we additionally tested our framework on this case study, which successfully confirmed its accuracy in risk assessment. Owing to its prototypical structure, our method could be easily upscaled both target- and resolution-wise, and both spatially and temporally, providing decision-makers with an innovative tool to reduce EID risk at national scales and limit the chances of international threats.