Abstract: The World Health Organization (WHO) has repeatedly called on countries to plan ahead for the outbreak of "Disease X". Analysis from various factors such as the characteristics of pathogenic microorganisms, the impact of human activities and abnormal climate, and the potential risks brought by the development of biotechnology shows that the occurrence of "Disease X" is inevitable. In recent years, the construction of our country's public health system has been further improved, but there is still room for improvement in the early identification, timely warning, rapid response, and technical reserves. Therefore, it is recommended to expand the content, objects, caliber, and channels of infectious disease monitoring at the national level, build a large database of genes covering human, animal, vector, and environmental microorganisms, empower pathogen risk assessment with technology, and build a more sensitive and intelligent infectious disease monitoring and early warning platform, and strengthen forward-looking research on vaccines and drugs. By advancing the "five fronts" - monitoring checkpoints, detection windows, "pathogen X" assessments, risk warnings, and technical reserves, we can effectively enhance China's ability to respond to "Disease X". As the first line of defense against cross-border transmission of infectious diseases, international border ports need to urgently strengthen international cooperation in epidemic disease surveillance and joint risk assessment, integrate port infectious disease prevention and control into the national prevention and control system, increase the technical reserves of pathogen detection at the frontline of ports, comprehensively strengthen the monitoring, identification, and early warning capabilities of unknown pathogens, and strengthen the national biosafety barrier.

Key words: Emerging infectious diseases, Disease X, Health and quarantine, National biosecurity