The COVID-19 pandemic was quite predictable and became a reminder to all of humanity that such events are inevitable. In light of what happened, significant and ongoing efforts embodied in national and international programs are needed to prepare for future pandemics, including those caused by unknown pathogens. The programs should include the development of diagnostic, preventive, and therapeutic tools. The diagnostic tools being developed should make it possible to quickly identify the unknown pathogen that initially caused this outbreak, and then allow for the examination of a large number of patients. This review discusses a plan for preparing the laboratory service for a future pandemic, as well as the main work carried out by researchers at the Center for Strategic Planning and Management of Medical and Biological Health Risks of the Federal Biomedical Agency, which is aimed at developing unique diagnostic solutions for the decoding of Disease X and establishing its optimal laboratory diagnostics.