Comparative Efficacy of Some Quinolones and Doxycycline Against Chronic Infection of Brucella melitensis 16M in BALB/c Mice

This study was under taken to observe various treatment methods for brucellosis caused byBrucella melitensis. The effect of therapeutic regimens with ciprofloxacin, ofloxacin and levofloxacinalone or in combination with doxycycline was assessed against B. melitensis chronic infection using200 mice. Doxycycline alone or in combination with ciprofloxacin was significantly found to reduce theinfection till 135 days post-infection (p<0.0001). Moreover, doxycycline was more effective than ciprofloxacinand ofloxacin 135 days post-infection (p = 0.04 and p = 0.02, respectively). However, treatment withquinolone-doxycycline combinations revealed synergistic effects as they were able to reduce the spleniccell forming unit (CFU) from day 45 post-infection. Similarly, doxycycline treatment reduced the spleniccolony forming unit (CFU) from day 90 post-infection. In conclusion, doxycycline seems to be the mosteffective agent against Brucella chronic infection.