In the era of AI, pandemics, and frequent disasters, informatics is no longer a matter of efficiency alone but of survival. We introduce Survival Informatics, a novel academic approach that emphasizes human well-being and societal resilience. Survival Informatics goes beyond traditional informatics by addressing fundamental issues of trust, inclusiveness, and sustainability, and by integrating ethical, legal, social, and economic perspectives into technical development. As one representative field where Survival Informatics can be practically implemented, the analysis of people’s reactions on social media provides a powerful means to capture public perceptions in real time and to link informatics research directly with societal well-being. Motivated by this perspective, we develop a stepwise technical framework that operationalizes the principles of Survival Informatics, highlighting a two-stage clustering approach for large-scale discourse analysis. Through a comprehensive case study of COVID-19 vaccine discourse in Japan, analyzing 32 million tweets, we demonstrate methodological innovations in scalability, reproducibility, and consistency. Finally, we discuss the broader implications of Survival Informatics for social implementation, including real-time public opinion monitoring, misinformation detection, and policy integration.