From coughs to complications: the story of Chlamydia pneumoniae.

Chlamydia pneumoniae is an obligate intracellular bacterium and a significant cause of respiratory infections. It is associated with upper and lower respiratory tract diseases, including bronchitis and pneumonia. The pathogen employs specific virulence factors, such as the Type III Secretion System (T3SS) and Inc proteins, to invade and subvert host cell machinery during its peculiar developmental life cycle. Chronic infections have been linked to asthma and, more controversially, to atherosclerosis and neurodegenerative diseases. Diagnosis primarily relies on PCR-based molecular assays, while treatment includes macrolides, tetracyclines or fluoroquinolones. Despite its clinical relevance, research on C. pneumoniae has declined in recent years, highlighting the need for renewed scientific focus.