This document defines biological disasters as scenarios involving large-scale disease, disability, or death among humans, animals, and plants caused by live organisms or their toxins. It discusses biological agents that could cause mass destruction, including anthrax, plague, and smallpox. The document categorizes biological agents based on their potential impact and ability to spread. It also covers epidemics, bioterrorism, historical events involving biological weapons, and the impact and prevention of biological disasters. Prevention methods include immunization, hygiene, surveillance, and protecting from weather extremes.