A CFD–GIS–QMRA framework for post‑release urban bioaerosol risk and healthcare demand assessment

Urban bioaerosol releases pose increasing challenges to urban biosecurity resilience, yet their public health impacts remain insufficiently assessed. Here, we developed an integrated CFD–GIS–QMRA framework to simulate bioaerosol dispersion, quantify infection risk, and estimate associated health outcomes and healthcare demand. Using hypothetical releases from a biosafety level 3 laboratory as a case study, we constructed multiple release scenarios involving four representative pathogens (SARS-CoV-2, H5N1, Anthracis, and Brucella) and three release sources (laboratory outlet vent, window, and ground). The results demonstrate that prevailing wind conditions and surrounding building geometry near the laboratory strongly shaped bioaerosol dispersion and deposition patterns. Substantial pathogen-specific differences were observed in infection risk, health outcomes, and healthcare demand. Specifically, SARS-CoV-2 resulted in the largest number of infections, Brucella generated the greatest hospitalization burden in terms of hospitalizations and total hospital days, while H5N1 resulted in the highest number of deaths and ICU admissions, as well as the greatest ICU-related healthcare resource demands, including ICU beds, nurses, and physicians. Quantitative assessment of health outcomes and healthcare demand provides practical support for healthcare-oriented emergency preparedness and medical resource allocation. The proposed end-to-end framework can support systematic urban bioaerosol risk assessment and also provide a scalable approach for diverse airborne hazards (e.g., chemical leaks and traffic-related air pollution) and urban exposure contexts (e.g., landfill sites and wastewater treatment plants).