Viral diseases that affect the respiratory tract
- Caused by numerous pathogens including respiratory syncytial virus, adenovirus, parainfluenza virus, rhinovirus, influenza virus, and SARS-CoV-2
- Viral respiratory tract infections may lead to pneumonia and be associated with asthma exacerbations
- Similar presenting symptoms include cough, fever, headache, and fatigue
- Physical examination may find wheezing, rhonchi, and acute respiratory distress
- Differentiating features:
- Viral infections typically do not persist for more than 10 days
- Symptoms that last longer are likely caused by bacterial infections
- Viral infections typically do not persist for more than 10 days
- Molecular testing using multiplex polymerase chain reaction methods (on respiratory specimens) or antigen detection (eg, respiratory syncytial virus antigens, influenza virus antigens) can be used if a definitive diagnosis is clinically indicated, the diagnosis remains in question, and confirmation will change management (Related: Respiratory syncytial virus infection)
- COVID-19 pandemic makes testing for SARS-CoV-2 widely indicated (eg, signs or symptoms consistent with COVID-19, known or suspected exposure to SARS-CoV-2)
- Guideline on community-acquired pneumonia from the American Thoracic Society and the Infectious Diseases Society of America recommends testing for influenza with a rapid influenza molecular assay (eg, influenza nucleic acid amplification test)
