Purpose: The article is devoted to the analysis of organizational measures to overcome the medical consequences of two large-scale events: the Chernobyl accident on 26.04.1986 and the COVID-19 pandemic. Results: A comparison of the causes, key factors, numbers affected and involved in these events persons, and the availability of the source of knowledge about the clinical picture, diagnosis, prevention and treatment of diseases, developing as a result of radiation exposure and the virus SARS-Cov-2. The article considers the availability of special medical institutions, the infectability of medical workers, the presence of long-term consequences for the health of victims and for the economy. Conclusions: In the development of such catastrophic events, an important role should be played by 1) Timely and adequate information to the population. 2) It is necessary to have a sufficient number of beds that can be repurposed in accordance with the needs and provided with appropriate equipment to support the vital functions of the body. 3) Planned training of qualified medical personnel should be carried out. 4) It is necessary to have stocks of emergency drugs close to the institutions where it is possible to receive victims.