Predicting mammal species suitable for Chagas disease spread

Given the risk of neglected diseases to humanity, can we predict how zoonotic diseases spread out? We have explored this by predicting mammal species reservoirs in the American continent that can act as potential blood-feeding sources of kissing bugs. Kissing bugs include 139 insect species of the Triatomine family that act as primary hosts of Trypanosoma cruzi, the causal agent of Chagas disease. T. cruzi also requires mammals as secondary hosts, yet our knowledge of which mammal species play such a role is uncertain. We analyzed trait data of mammal species documented as feeding sources to predict which other non-documented mammal species could then act as potential hosts. Using extreme gradient-boosted regression and having mammal traits as predictive variables, we found that 573 mammal species out of 1,923 species could be potential feeding sources of triatomines and, thus, reservoirs of T. cruzi. According to our analysis, triatomines overlap with these 573 mammal species on the basis of habitats, ambient temperature, and humidity. These insects also make use of mammals species that are heavier than 1 kg. Our estimate implies that controlling Chagas diseases is far more complex as the variety of potential mammal host species is extremely high. Also, the dynamics of Chagas disease may impose negative selection on many mammals in the wild.