Respiratory Syncytial Virus: Spectrum of Clinical Manifestations and Complications in Children

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infection in infants and young children. Despite its substantial disease burden, no effective vaccine is available. Clinical manifestations of RSV encompass the spectrum of acute upper and lower respiratory tract infection. Hallmarks of the virus are its propensity to progress to lower respiratory disease and to cause disproportionate disease severity at extremes of ages. Acute RSV infection may be complicated by secondary bacterial infections and respiratory failure requiring mechanical ventilation and prolonged hospitalization. In the developed world, most RSV infections are self-limited; however, globally, RSV is a significant cause of mortality in children younger than age 5 years. Severe RSV infection in infancy has also been associated with the development of childhood asthma. Thus, the extensive disease burden of RSV and its attributable mortality portend the urgency of vaccine development targeted toward populations disproportionately affected by severe disease. [ Pediatr Ann. 2019;48(9):e349–e353.]