Historically, sociologists have taken little interest in epidemics or pandemics. An important exception is PM Strong’s work, inspired by the experience of HIV/AIDS in the 1980s. Strong proposed that all viral or bacterial epidemics were accompanied by three societal epidemics: of fear; of explanation and moralisation; and of action. This model is applied to the Covid-19 pandemic of 2020-2023. The chapter notes the pervasive influence of fear - on biomedical and public health scientists as much as the general population - and its use as an instrument of governance. It considers the moralising of both conspiracy and Zero-Covid advocates. It shows the turn to biomedicine in response to demands for action and the creation of space for a resurgent biomedical imperialism. Democracy gave way to iatrocracy, rule by biomedicine. The chapter concludes by reflecting on sociologists’ responsibility to examine medicine as a social institution rather than being co-opted to its agenda.