Viral pneumonia is mainly an inflammation of the lungs caused by viral infections such as influenza virus and adenovirus, with associated factors such as immunosuppression. 1. Etiology: Viral pneumonia is mainly an inhalation infection of viruses, transmitted through droplets. Common causative viruses include influenza A and B viruses, adenoviruses, parainfluenza viruses, respiratory syncytial viruses and coronaviruses. Virus invasion can cause interstitial and parenchymal inflammation, i.e. pneumonia. 2. Associated factors: Virus susceptibility is also related to the immunosuppressive status of the host. For example, bone marrow transplant and organ transplant recipients are more susceptible to herpesvirus or cytomegalovirus pneumonia. If you feel unwell, prompt medical attention is recommended.