Susceptibility of Bacillus anthracis to eleven antimicrobial agents including novel fluoroquinolones and a ketolide.
OBJECTIVE
To determine the susceptibility of southern African strains of Bacillus anthracis to new, investigational agents as well as conventional antibiotics.


METHODS
The MICs of 26 isolates of B. anthracis from South Africa and Zimbabwe, as well as the Sterne vaccine strain and a type culture strain, were determined by agar dilution.


RESULTS
The most active antimicrobial agents were the novel ketolide ABT 773, new and conventional fluoroquinolones, and doxycycline; macrolides were intermediately active. The lack of activity of extended-spectrum cephalosporins against B. anthracis was confirmed.


CONCLUSIONS
Susceptibility to conventional antibiotics was in keeping with previous studies. Two new fluoroquinolones and a ketolide showed promising in vitro activity that would support their further evaluation in animal models of anthrax.
Frean
John
J
National Institute for Communicable Diseases, National Health Laboratory Service, Johannesburg, South Africa.
Klugman
Keith P
KP
Arntzen
Lorraine
L
Bukofzer
Stanley
S
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001408:Bacillus anthracis / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D024881:Drug Resistance, Bacterial / Q000502:physiology*; D004917:Erythromycin / Q000031:analogs & derivatives / Q000494:pharmacology*; D024841:Fluoroquinolones; D006801:Humans; D048628:Ketolides; D008826:Microbial Sensitivity Tests; D001618:beta-Lactamases / Q000096:biosynthesis
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D048628:Ketolides; D004917:Erythromycin; D001618:beta-Lactamases; C405499:cethromycin