Which bacterium is recognized as a potential agent of bioterrorism and is historically associated with plague?

• A. Yersinia pestis
• B. Bacillus anthracis
• C. Francisella tularensis
• D. Brucella melitensis

Answer: (A)

Yersinia pestis is the bacterium tied to plague and recognized as a potential bioterrorism agent. It has caused major plague outbreaks for centuries, including the Black Death, anchoring its historic association with plague. The concern in bioterrorism terms comes from its ability to cause pneumonic plague, which can spread from person to person through respiratory droplets, leading to rapid and potentially widespread illness. Its virulence and the potential for aerosol transmission make it a notable threat in preparedness discussions. The other organisms listed cause different diseases—anthrax, tularemia, and brucellosis—and, while they are also serious pathogens, they are not the agent historically linked to plague.