Emerging pathogens refer to microorganisms that have newly appeared and crossed species barriers to infect humans for the first time, or new strains generated by gene mutation and recombination of known pathogens with enhanced transmissibility, virulence or drug resistance. They mainly include novel viruses, drug-resistant bacteria, variant fungi and so on. Most emerging pathogens are zoonotic pathogens naturally harbored in wild animals. Driven by external factors, they trigger cross-species spillover and pose continuous threats to global public health security. Compared with conventional pathogens, emerging pathogens are generally characterized by rapid mutation, hidden transmission, non-specific clinical symptoms and universal population susceptibility. In the early stage, mature detection methods, specific medicines and preventive vaccines are usually unavailable, which may easily lead to clustered outbreaks or even global pandemics.
The continuous emergence of emerging pathogens results from the combined effects of natural environments and human social activities. Global climate change expands the habitats and extends the activity cycles of vector organisms, broadening the transmission range of infectious diseases. Meanwhile, deforestation, ecological degradation and increased human-wildlife contact greatly raise the probability of cross-host pathogen spillover. High-frequency movement of people and goods brought by economic globalization enables locally erupted outbreaks to spread across borders within a short period. In addition, antibiotic overuse, the growing immunocompromised population and intensive farming accelerate pathogen mutation and the emergence of drug-resistant strains, further complicating the prevention and control of emerging infectious diseases.
Faced with risks of emerging infectious diseases, the international community generally builds an integrated prevention and control system covering humans, animals and the environment based on the "One Health" concept. The top priority is to strengthen source surveillance and early warning, improve sentinel surveillance networks for unexplained fever and unexplained pneumonia, and deploy pathogen genome sequencing technology to rapidly identify pathogens, trace origins and assess mutation risks, shifting from passive response to proactive early warning. Secondly, standardize emergency response procedures for epidemics, implement early isolation of cases, contact tracing, disinfection of epidemic sites and healthcare-associated infection control to quickly break transmission chains and contain epidemic spread.
It is also essential to continuously strengthen core public health capacity, upgrade high-containment biosafety laboratory systems, establish platforms for rapid vaccine development, diagnostic reagent innovation and antiviral drug research, and improve emergency stockpiling mechanisms. Cross-sectoral, cross-regional and cross-border collaborative prevention should be promoted. Multiple sectors including health, forestry, ports and animal husbandry carry out comprehensive governance, strengthening wildlife management, vector control and entry quarantine screening. Moreover, regular public health education should be conducted to improve self-protection awareness and public health literacy of communities. Systematic and routine prevention and control measures can effectively enhance emergency response capacity against emerging pathogens and consolidate the defense line of global public health security.
