Respiratory Syncytial Virus: Epidemiology, Burden of Disease, and Clinical Update.

Respiratory syncytial virus (RSV) is a common viral pathogen that accounts about 33 million cases of acute lower respiratory tract infection (LRTI) worldwide in children under the age of 5 years each year. High-risk populations, particularly preterm infants, those with underlying chronic lung disease, congenital heart disease, or compromised immune systems, are afflicted most significantly. RSV infection is characterized by significant amount of mucus and submucosal edema in the respiratory tract, leading to congestion and, oftentimes, significant respiratory distress. Antigen- and PCR-based testing are used to diagnose RSV infection.