Draft genome and plasmid sequences of Chlamydia pneumoniae strain B21 from an Australian endangered marsupial, the western barred bandicoot

Chlamydia pneumoniae is a ubiquitous intracellular pathogen, first associated with human respiratory disease and subsequently detected in a range of mammals, amphibians, and reptiles. Here we report the draft genome sequence for strain B21 of C. pneumoniae, isolated from the endangered Australian marsupial the western barred bandicoot

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 μg/ml) and lower level resistance to rifalazil (0.5 to 1 μg/ml). C. pneumoniae TW-183 developed only low-level resistance to rifampin (0.25 μg/ml) and rifalazil (0.016 μg/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

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 μg/ml (ranges, 0.125 to 0.5 μg/ml for C. trachomatis and 0.25 to 1.0 μg/ml for C. pneumoniae)

Association between otitis media infection and failed hearing screenings in children.

This study aims to assess prospectively whether there is an association between frequencies of upper respiratory tract infections (URTI) or asthma in early childhood and failed otoacoustic emission (OAE) screenings later in life. There are no clear recommendations for hearing testing following acute otitis media (AOM) infection. This is a retrospective, practice based chart review. Participants from a primary care setting were 517 pre-adolescent and adolescent children (49.9% female) (ages 10-21; mean, 15 y/o), who had presented with at least one specific bacterial URTI (AOM, Group A Streptococcus (GAS) tonsillitis, or Influenza) during childhood. Hearing testing was recorded incidentally at all subsequent routine health care maintenance visits (OAE hearing screen). Simple linear regression analyses were performed using R (v3.4.4). We found that number of episodes of AOM infections strongly correlated with number of failed OAE screenings later in life (F = 76.37; P = <0.001; R2 = 0.1279), while GAS (F = 1.859; P = 0.1733; R2 = 0.0016) or Influenza infection (F = 2.624; P = 0.1059; R2 = 0.0031) were not associated with failed OAE screening. Correlation between number of AOM infections and number of failed OAE screenings was not strengthened by presence of asthma. This study found evidence of an association between childhood history of AOM and failed OAE screenings in adolescence. Since this population may be at a higher risk for developing permanent or fluctuating hearing losses, further studies to clarify indications and timing of standard audiological testing among these children should be considered