Which organism is the causative agent of brucellosis?

Which organism is the causative agent of brucellosis?

• A. Yersinia pestis
• B. Brucella spp.
• C. Coxiella burnetii
• D. Bacillus cereus

Answer: (B)

Brucellosis is caused by Brucella species, a small Gram-negative bacterium that can live inside host cells. Humans typically acquire it through contact with infected animals or by consuming unpasteurized dairy products from those animals. The Brucella genus includes several species—such as B. melitensis, B. abortus, and B. suis—that are classic culprits in human brucellosis. The other organisms listed are linked to different diseases (plague, Q fever, and food poisoning, respectively), so they don’t explain brucellosis.

Brucellosis is caused by Brucella species, a small Gram-negative bacterium that can live inside host cells. Humans typically acquire it through contact with infected animals or by consuming unpasteurized dairy products from those animals. The Brucella genus includes several species—such as B. melitensis, B. abortus, and B. suis—that are classic culprits in human brucellosis. The other organisms listed are linked to different diseases (plague, Q fever, and food poisoning, respectively), so they don’t explain brucellosis.