Activity of Nafithromycin (WCK 4873) against Chlamydia pneumoniae.

VoRSUNY DownstatePediatricsN/

In Vitro Activity of Levonadifloxacin (WCK 771) against Chlamydia pneumoniae

VoRSUNY DownstatePediatricsN/

In vitro activity of nemonoxacin, a novel nonfluorinated quinolone antibiotic, against Chlamydia trachomatis and Chlamydia pneumoniae.

The in vitro activities of nemonoxacin, levofloxacin, azithromycin, and doxycycline were tested against 10 isolates each of Chlamydia trachomatis and Chlamydia pneumoniae. The MICs at which 90% of the isolates of both C. trachomatis and C. pneumoniae were inhibited (MIC90s) were 0.06 μg/ml (range, 0.03 to 0.13 μg/ml). The minimal bactericidal concentrations at which 90% of the isolates were killed by nemonoxacin (MBC90s) were 0.06 μg/ml for C. trachomatis (range, 0.03 to 0.125 μg/ml) and 0.25 for C. pneumoniae (range, 0.015 to 0.5 μg/ml).VoRSUNY DownstatePediatricsN/

In Vitro Activity of Omadacycline against Chlamydia pneumoniae

The activities of omadacycline, azithromycin, doxycycline, moxifloxacin, and levofloxacin were tested against 15 isolates of The minimum inhibitory concentration at which 90% of the isolates of were inhibited by omadacycline was 0.25 μg/ml (range, 0.03 to 0.5 μg/ml).VoRSUNY DownstatePediatricsN/

Coronavirus disease 2019 prevalence rates in reopened private schools in New York City: Impact of diagnostic methods.

VoRSUNY DownstatePediatricsN/

In vitro activity of AZD0914, a novel DNA gyrase inhibitor, against Chlamydia trachomatis and Chlamydia pneumoniae.

The in vitro activities of AZD0914, levofloxacin, azithromycin, and doxycycline against 10 isolates each of Chlamydia trachomatis and Chlamydia pneumoniae were tested. For AZD0914, the MIC90s for C. trachomatis and C. pneumoniae were 0.25 μg/ml (range, 0.06 to 0.5 μg/ml) and 1 μg/ml (range, 0.25 to 1 μg/ml), respectively, and the minimal bactericidal concentrations at which 90% of the isolates were killed (MBC90s) were 0.5 μg/ml for C. trachomatis (range, 0.125 to 1 μg/ml) and 2 μg/ml for C. pneumoniae (range, 0.5 to 2 μg/ml).VoRSUNY DownstatePediatricsN/

Coronavirus disease 2019 (COVID-19) infection rates in a private school in Brooklyn, New York.

VoRSUNY DownstatePediatricsN/

In vitro activity of CEM-101, a new fluoroketolide antibiotic, against Chlamydia trachomatis and Chlamydia (Chlamydophila) pneumoniae.

The in vitro activities of CEM-101, telithromycin, azithromycin, clarithromycin, and doxycycline against 10 isolates each of Chlamydia trachomatis and Chlamydia (Chlamydophila) pneumoniae were tested. The MIC at which 90% of the isolates of both C. trachomatis and C. pneumoniae were inhibited and the minimal bactericidal concentration at which 90% of the isolates were killed by CEM-101 were 0.25 microg/ml (ranges, 0.125 to 0.5 microg/ml for C. trachomatis and 0.25 to 1.0 microg/ml for C. pneumoniae).VoRSUNY DownstatePediatricsN/

Emergence of resistance to rifampin and rifalazil in Chlamydophila pneumoniae and Chlamydia trachomatis.

Although rifamycins have excellent activity against Chlamydophila pneumoniae and Chlamydia trachomatis in vitro, concerns about the possible development of resistance during therapy have discouraged their use for treatment of chlamydial infections. Rifalazil, a new semisynthetic rifamycin with a long half-life, is the most active antimicrobial against C. pneumoniae and C. trachomatis in vitro, indicating its potential for treatment of acute and chronic C. pneumoniae and C. trachomatis infections. We investigated the effect of serial passage of two C. pneumoniae isolates and two serotypes of C. trachomatis in subinhibitory concentrations of rifalazil and rifampin on the development of phenotypic and genotypic resistance. C. trachomatis developed resistance to both antimicrobials within six passages, with higher level resistance to rifampin (128 to 256 microg/ml) and lower level resistance to rifalazil (0.5 to 1 microg/ml). C. pneumoniae TW-183 developed only low-level resistance to rifampin (0.25 microg/ml) and rifalazil (0.016 microg/ml) after 12 passages. C. pneumoniae CWL-029 failed to develop resistance to either drug. Two unique mutations emerged in the rpoB gene of rifampin (L456I) and rifalazil (D461E)-resistant C. pneumoniae TW-183. A single mutation (H471Y) was detected in both rifampin- and rifalazil-resistant C. trachomatis UW-3/Cx/D, and a unique mutation (V136F) was found in rifalazil-resistant BU-434/L(2). No mutations were detected in the entire rpoB gene of rifampin-resistant BU-434/L(2). This is the first description of antibiotic resistance-associated mutations in C. pneumoniae and of rifampin resistance in C. trachomatis not associated with mutations in the rpoB gene.VoRSUNY DownstatePediatricsN/