Through the story of the live poliovirus vaccines spanning four continents, this research charts the pre-history of contemporary polio eradication programs. More specifically, I focus on polio vaccine testing and their evaluation, epidemiological data collection and vaccination policies. The temporal framework is marked by transnational debates that took place in medical journals and at international conferences in the 1950s and the launch of the Global Polio Eradication Initiative in 1988. In this new work, I will provide a historical analysis of how polio prevention became a global project and what the roles of international agencies, pharmaceutical companies, individual researchers and the experience of research subjects were in the process. Thus, in part this research asks how one particular vaccine became the technology of choice in the formative years of international health agencies and parallel eradication campaigns, and more broadly it reveals the roots of global pharmaceutical testing in the early Cold War era.