Abstract Background The establishment of martial law due to Russia’s military aggression against Ukraine led to specific adjustments in the functioning of the Centers for Diseases Control and Prevention (СDС). The negative impact of hostilities is determined by the increased morbidity rate of communicable and non-communicable diseases, insufficient supply of safe drinking water and food to damaged sites, inadequate living conditions, etc. Objectives The purpose of the work was to create an effective system for responding to biological, chemical and radiation hazards and eliminating the consequences of an emergency situation in the realities of martial law. Methods We used the most common methods, namely descriptive, statistical, microbiological and сhemical laboratory tests. Results The activities of the CDC under martial law include daily monitoring studies of environmental objects. The epidemic situation of acute intestinal infection (AII) and other communicable diseases (CD) is constantly analyzed. The Kyiv Oblast CDC became the basic institution for the implementation of the ‘pilot project’ in the direction of sanitary and epidemic assessment and monitoring of environmetal objects in 188 de-occupied areas. The main public health risks were identified: providing the population with high-quality drinking water; low immunization rate of the population; sites for the location of internally displaced persons; natural foci of especially dangerous diseases, such as tularemia, leptospirosis, infection fevers, etc. In 2022, the overall level of CD in the Kyiv region decreased by 44.0% from 2021. The most common nosologies were acute respiratory viral infections and influenza (98.9%), AII (42.4%), tuberculosis (15.3%), Lyme disease (15.3%), and viral hepatitis (14.2%). Conclusions Based on the research conducted, mechanisms have been developed for responding to hazards of various origins by public health institutions, including risk assessmant and laboratory studies. Key messages • The main focus of the Centers for Diseases Control and Prevention is aimed at effective response to hazards of various origins in order to ensure public health under martial law. • Risk assessment in de-occupied territories has become an important tool for identifying correct approaches to prevent negative consequences for public health.