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Question 4#

A bioterrorist attacks your city, sprinkling a white powder over a half-mile-long crowd attending a parade.

What antibiotic prophylaxis is Most appropriate? 

A. Rifampin 1 g orally to all people within a 1-mile radius of the attack
B. Azithromycin 500 mg orally to all people exposed to the powder
C. Ciprofloxacin, levofloxacin, or doxycycline orally to all people older exposed to the powder
D. Ciprofloxacin 500 mg orally to all people over 5 years of age within a 1-mile radius of the attack, rifampin 500 mg to all people under 5 years of age within a 1-mile radius of the attack

Correct Answer is C


Correct Answer: C

There are three FDA-approved drugs for Bacillus anthracis (anthrax) postexposure prophylaxis for adults 18 years of age and older: ciprofloxacin, levofloxacin, and doxycycline. Current guidelines recommend 60 days of treatment with one of these medications for adults. Although fluoroquinolones are generally not used for infection treatment or prophylaxis in children, and doxycycline is avoided in children younger than 8 years of age, it is generally agreed-upon that the benefits of prophylaxis with these medications in children outweigh potential toxicities in the setting of anthrax exposure. Prophylaxis should be given as soon as possible after exposure, as efficacy diminishes with time since exposure. Three doses of anthrax vaccine adsorbed are also recommended concurrently with antibiotic prophylaxis. Rifampin is often given for prophylaxis to people exposed to N. meningitides but is not used for anthrax exposure.


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