A viral disease (or viral infection) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles (virions) attach to and enter susceptible cells.
medical cause of Acute bronchitis
medical cause of Bronchiolitis
medical cause of Bronchiectasis
medical cause of Hemoptysis
complications of Bronchiolitis
medical cause of Sinusitis
complications of Pharyngitis
symptom of Bronchiectasis