Chlamydia pneumoniae, strain TWAR pneumonia.

Chlamydia pneumoniae, strain TWAR is a newly recognized third species of Chlamydia. It is an important cause of pneumonia, bronchitis, sinusitis, and other acute respiratory infections. It is a human pathogen transmitted by the respiratory route. Successful antibiotic treatment with tetracycline or erythromycin requires high dosage and a prolonged course.