Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 32-06: Common Viral Respiratory Infections + Key Features Download Section PDF Listen +++ ++ Bronchiolitis, proliferation and necrosis of bronchiolar epithelium develop, producing obstruction from sloughed epithelium and increased mucus secretion Apnea, low-grade fever, tachypnea, and wheezes Hyperinflated lungs, decreased gas exchange, and increased work of breathing Prematurity is a major risk factor for severe disease + Clinical Findings Download Section PDF Listen +++ ++ Annual epidemics occur in winter and spring Average incubation period is 5 days Inoculation may occur through the nose or the eyes In children Most common cause of acute lower respiratory infection Common cause of acute and recurrent otitis media In adults Causes upper and lower respiratory tract infection with increasingly recognized severity in Persons with comorbid conditions Elderly persons Persons with severe combined immunodeficiency Persons who have undergone lung or bone marrow transplantation Recurrent infections occur throughout life In immunocompromised patients, such as bone marrow transplant recipients, serious pneumonia can occur + Diagnosis Download Section PDF Listen +++ ++ Polymerase chain reaction (PCR) is used Rapid diagnosis possible by viral antigen identification in nasal washings using an ELISA or immunofluorescent assay Multiplex assays in conjunction with influenza A and B tests are available commercially RSV viral load assay values at day 3 of infection correlate with requirement of intensive care and respiratory failure + Treatment Download Section PDF Listen +++ ++ Hydration, humidification of inspired air, antibiotic therapy, and ventilatory support as needed In non–high-risk populations, ribavirin, bronchodilators, and corticosteroids are widely used, but evidence for their effectiveness is lacking Ribavirin contraindicated in pregnancy Palivizumab Prophylactic monoclonal antibody Effective in high-risk infants (congenital heart and lung diseases, Down syndrome) Significantly lowers incidence of recurrent wheezing Not proven effective among adults with RSV Azithromycin therapy has been shown to reduce the probability of recurrent wheezing during the subsequent year by approximately 50%