Trait based assessment of the invasion potential of disease vector mosquitoes

Abstract

Mosquito-borne diseases pose a growing global health threat, largely driven by the human-mediated spread of vector species beyond their native regions. Although only a few mosquito species historically established populations outside their native ranges, many have expanded rapidly in recent decades. Once established, these invaders are notoriously difficult to control, emphasizing the need for proactive identification before human-mediated spread occurs. Here, we present a framework to anticipate invasion potential for 184 mosquito species of medical importance based on their ecological, life-history, and macroecological traits. We first compiled a comprehensive dataset of 26 traits characterizing each species. We then used random forest models to relate these traits with the probability of species being introduced in new regions (before and after 1950, marking the onset of widespread trade globalization), and of establishment following introduction. Models achieved moderate to good predictive performance (AUC = 0.78-0.85) and revealed that species native to Asia and Australia, adapted to human-made breeding sites, and tolerant of climatic extremes are consistently more likely to be introduced and to establish in non-native regions. Among species with no known invasion history, we identified 24 with higher potential to become future spreaders, of which 17 also exhibit high establishment probabilities ( high-risk species). These results show that invasion potential can be inferred, to some extent, from intrinsic species traits and provide a quantitative basis for proactive surveillance, enabling prioritization of species most likely to become introduced in the future. Author SummaryMosquito-borne diseases threaten more than half of the worlds population and cause over 700,000 deaths each year. Only a small share of mosquito species can spread these diseases, but some of them are moving into new regions where they have never been seen before. The spread of these mosquitoes has led to increasing numbers of locally transmitted outbreaks in regions that previously, or in recent times, had no mosquito-borne diseases. Human activities like trade and travel help mosquitoes spread, and once they arrive, they are extremely difficult to eradicate. Therefore, it is crucial to understand which species may spread in the future and to identify those that should be closely monitored to prevent their introduction and establishment. In this work, we linked species characteristics with their known invasion history to identify the factors driving their introduction and establishment in new regions. We found that species from Asia and Australia, capable of using human-made breeding sites, and tolerant of climatic extremes are most likely to become invaders. We then used these findings to predict which species might spread next. We identified 24 species with high invasion potential, including 17 that also have high chances of establishing once introduced. These results demonstrate that invasion risk can be predicted from measurable species traits, providing a framework to guide early-warning surveillance and prioritize species for monitoring before they begin spreading and become widespread vectors of human disease.