Pulmonary fibrosis (PF) is a severe consequence of respiratory infections, characterized by excessive extracellular matrix deposition and irreversible lung architectural damage. Once considered a rare condition, PF is now increasingly recognized in the wake of viral infections, particularly among survivors of viral-induced acute respiratory distress syndrome (ARDS). The COVID-19 pandemic has highlighted in bold relief the observation that many survivors of severe viral pneumonia do not recover fully but develop chronic fibrotic changes that impair lung function. This review examines the clinical evidence and underlying mechanisms linking viral infections—COVID-19, influenza, and other respiratory viruses—to the onset of pulmonary fibrosis. By probing the mechanisms of cellular injury, immune dysregulation, and aberrant repair mechanisms, we aim to illuminate the pathways that transform an acute viral insult into a chronic, fibrotic disease.
Kass-Gergi et al. (2025) studied this question.