Which antibiotic classes are used to treat both anthrax and Yersinia pestis plague?

Which antibiotic classes are used to treat both anthrax and Yersinia pestis plague?

• A. Carbapenems or cephalosporins
• B. Macrolides or penicillins
• C. Fluoroquinolones or tetracyclines
• D. Aminoglycosides or sulfonamides

Answer: (C)

The key concept is that both Bacillus anthracis and Yersinia pestis are effectively targeted by the same antibiotic classes: fluoroquinolones and tetracyclines. Fluoroquinolones (like ciprofloxacin or levofloxacin) disrupt bacterial DNA replication by inhibiting DNA gyrase and topoisomerase IV, which works well against these organisms. Tetracyclines (like doxycycline) block the 30S ribosomal subunit, stopping protein synthesis, and are similarly active against both pathogens. Clinically, inhalational anthrax is treated with a fluoroquinolone or doxycycline, and plague can be treated with a fluoroquinolone or doxycycline as part of standard regimens, with other agents used in different settings. This broad activity across both diseases is why these classes are the best answer.

The key concept is that both Bacillus anthracis and Yersinia pestis are effectively targeted by the same antibiotic classes: fluoroquinolones and tetracyclines. Fluoroquinolones (like ciprofloxacin or levofloxacin) disrupt bacterial DNA replication by inhibiting DNA gyrase and topoisomerase IV, which works well against these organisms. Tetracyclines (like doxycycline) block the 30S ribosomal subunit, stopping protein synthesis, and are similarly active against both pathogens. Clinically, inhalational anthrax is treated with a fluoroquinolone or doxycycline, and plague can be treated with a fluoroquinolone or doxycycline as part of standard regimens, with other agents used in different settings. This broad activity across both diseases is why these classes are the best answer.