This article considers health and human rights implications for people deprived of liberty during the COVID-19 crisis. The health risks of incarceration for individual and community health, particularly in overcrowded and underresourced prisons and detention centers, are well known, but with the COVID-19 pandemic have become a public health emergency. Physical distancing in prisons is hardly manageable, and protective means are poor or lacking. Emergency releases have been shown to be feasible in terms of public safety but lack sustainability in reducing the number of people living in detention, and, globally, only a small proportion of them have been released. Without controlling the infection inside prisons, global efforts to tackle the spread of the disease may fail. People living in detention are not only more vulnerable to infection with COVID-19 but they are also especially vulnerable to human rights violations induced by inappropriate restrictions under the pretext of infection control. Therefore, alternatives for detention should be promoted and the number of incarcerated people radically decreased. This article calls on policymakers and all professionals involved in public health and criminal justice not to waste the opportunities provided by the crisis but to act now.