The paper proposes the classification of health security as one of the non-military security dimensions of the second generation, determined more by globalization processes than by the end of the Cold War (first generation). The cognitive goal of the article is to identify and analyse the elements of the structure of international health security such as 1) the essence and specificity of securitization of threats to health security; 2) health security threats; 3) the referent object or whom it concerns; and 4) measures to ensure it. Specific to this dimension is the political motivation for its securitization. In the world of interrelated and global mobilities, what is significant for health security is the diversity of the development level, preferred values, and, consequently, the diversity of sensitivity and susceptibility of national healthcare systems to cross-border threats.