To date, over 4 million people globally have been infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), resulting in more than 250 000 deaths. Populations at particular risk include many of the most vulnerable sectors of society: incarcerated people, those residing in long-term care, minorities, and people with substance use disorders. Considering the high mortality rates attributable to the ongoing opioid overdose crisis, those who use illicit substances are now caught up in two simultaneous public health emergencies. This group might be additionally disadvantaged by barriers to the implementation of public health measures aimed at reducing virus transmission (eg, physical distancing) due to a myriad of social and structural issues including poverty, unstable employment, marginalisation, and homelessness, while having higher rates of comorbidities that portend worse outcomes if they become infected.