Which biological agent is known for causing plague?

Yersinia pestis is the bacterium responsible for causing plague, a severe infectious disease characterized by symptoms such as fever, chills, and swollen lymph nodes. This pathogen is primarily transmitted to humans through the bite of infected fleas that reside on rats and other rodents. When Yersinia pestis enters the body, it can multiply rapidly, leading to potentially life-threatening conditions if not treated promptly. The identification of Yersinia pestis is crucial in public health and military contexts, particularly for understanding the epidemiology of plague and implementing control measures to prevent outbreaks. Understanding the characteristics and transmission methods of Yersinia pestis is vital for effective medical management in biological casualty situations.