Antibiotic Treatment in Mice Infected with Japanese Borrelia garinii: Efficacy of Ceftriaxone for Eradicating the Infection Induced by Ixodes persulcatus Tick Bites

Abstract

We compared the efficacy of three antibiotics (ceftriaxone, erythromycin and clarithromycin) against Borrelia garinii infection in mice. The nymphal ticks of Ixodes persulcatus infected with the strain JEM6 of Japanese B. garinii were allowed to feed on female C3H mice. The mice were treated with each of the antibiotics for 5 consecutive days 1, 3, or 7 weeks after tick detachment. The doses of antibiotics per day were as follows: 5 mg intraperitoneal injection of ceftriaxone, 2 mg intraperitoneal injection of erythromycin and 1 mg peroral administration of clarithromycin. The infection status in treated mice was monitored by culturing their earlobes, hearts and urinary bladders in BSK II medium. Ceftriaxone eliminated borreliae completely; however, a recurrence of infection was observed in mice treated with erythromycin and clarithromycin.

Duration of immunity to reinfection with tick-transmitted Borrelia burgdorferi in naturally infected mice

“…Although all of the mice exposed to antibiotics in the present study were presumed to be cured based on a negative ear biopsy, the possibility that antibiotic treatment decreases the spirochete load in the host to the point where organisms are difficult to culture but are still present exists. This phenomenon has previously been described for dogs (28) and mice (14). If this was the case in our experiments, the infections seen in challenged mice may have been due to relapses after treatment rather than to true reinfection.…”

Effect of clarithromycin on the cell profile of bronchoalveolar lavage fluid in mice with neutrophil-predominant lung disease

“…Based on previous study protocols 14,15 in experimental models, we used a dosage of 50 mg/kg/day. The treatment was initiated 2 days before the intranasal challenge with P. aeruginosa.…”