This book contributes to the exploration of the concept of time in the social sciences and philosophy, by reflecting on the ontological presuppositions of the logic of medical science and what this means for the response to communicable infection. By examining infection as a process that resists segmentation, prediction, and control, the author exposes the ontological limits of linear divisible time as it is routinely mobilised by biomedicine and health governance to make life knowable and governable. Rather than abandoning time, it recognises it as a powerful technical device, one that has come to be treated as a mirror of reality rather than as an intervention that actively shapes what can be known, valued, and acted upon in the face of potentially lethal infection. The book will appeal to scholars in sociology, social theory, philosophy, and medical science interested in temporality, conceptions of power, and speculative thought.