Ricardo Castillo-Neyra, PhD, DVM, MSPH, is an Assistant Professor of Epidemiology at the Perelman School of Medicine at the University of Pennsylvania and the Scientific Director of the Zoonotic Diseases Research Laboratory (ZDRL), a collaborative research consortium between multiple US-based and international institutions that employs over 30 full-time staff. He systematically applies the One Health approach to studying tropical infectious diseases in Latin America. Dr. Castillo has focused his research on the epidemiology of zoonotic diseases in urban areas, the fastest-growing ecosystems in the world. Dr. Castillo is the PI of two NIH-funded projects focused on the socio-spatial dynamics of urban zoonotic diseases and the optimization of mass vaccination campaigns to control epidemics. He is also the Co-PI of a Mellon Foundation project where he studies the intersection of social inequalities, access to health services, and the emergence of infectious diseases.