The impact of biomedicine and biomedical technologies on identity and sociality has long been the focus of medical anthropology. In this article we revisit these debates in a discussion of how unprecedented encounters with biomedicine during the West African Ebola outbreak have featured in Sierra Leoneans’ understandings of citizenship and belonging, using the case study of an Ebola vaccine trial taking place in Kambia District (EBOVAC Salone). Analysing our ethnographic material in conversation with a historical analysis of notions of belonging and citizenship, we show how participation in a vaccine trial in a moment of crisis allowed people to tell stories about themselves as political subjects and to situate themselves in a conversation about the nature of citizenship that both pre-dates and post-dates the epidemic.