[Viral pneumonia. COVID-19 pneumonia].

Viruses are becoming more and more important as etiological agents of pneumonia, mainly due to improvements in diagnostic techniques. At present, they account for approximately one-third of community-acquired pneumonia cases. They tend to occur in children and elderly patients, causing anything from mild cases to severe cases which require intubation and intensive care. The main causative agents include rhinovirus, influenza virus A or B, metapneumovirus, respiratory syncytial virus, parainfluenza virus, coronavirus, or adenovirus. Infection produced by SARS-CoV-2, the cause of the current COVID-19 pandemic, which has had devastating consequences, is proof of the vital importance of viral pneumonia. This is the main subject of this update. Drawing on the abundant information available, which has been continuously evolving since the beginning of the pandemic, this section will review the main characteristics of the virus, its pathophysiology, and its clinical manifestations as well as the main diagnostic and treatment methods.