A new interdisciplinary study examines how the global legal and illegal wildlife trade can contribute to disease spillover from animals to humans. The research focuses on the movement of mammals through wildlife markets and other trade pathways, where frequent handling and close contact among animals—and between animals and people—can allow pathogens to jump between species. Scientists already recognize that several major diseases, including HIV, SARS, and Ebola, can originate in animals and later infect humans. This study is described as one of the first to quantify the public-health risks associated with wildlife commerce by assessing pathogen sharing between traded mammals and humans using available trade data. The findings indicate that nearly half of traded mammals share at least one pathogen with people, implying that many traded species can carry microbes relevant to human infection. The outlets also emphasize that wildlife trade expansion increases the number of routes and interfaces through which pathogens may spread, combining human exposure with pathogen diversity carried by wild animals and the broader wildlife-livestock-human environment.